Drag racing the GMT360 with the LL8

rchalmers3

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Jul 11, 2020
207
Irmo, SC
I am curious to learn if there are forum members who possess knowledge and wisdom of racing these trucks, or general drag racing knowledge that they are willing to share. I have started a long term project and could use some advise and guidance on various aspects of the build. I have numerous ideas on what I'd like to do, and am seeking opinions and advise about the validity of my assumptions. Obviously, I do not possess racing experience, so I look forward to hearing from this group.

Thanks in advance,
Rick
 

mrrsm

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While modifying the GM Atlas LL8 has been the passing fancy of many a GMT360 Owner-Mechanic, very few have been successful in doing so. The poor returns on the investment of Time, Energy and Money for the often paltry amount of additional Horse Power and Torque to be gained is generally the source of them suffering from the inevitable “Vortec 4200 Performance Build Buzz Kill”.

The problems facing you right out of the box is the terrible dearth of useful After-Market racing components and Tuning that can easily be added as mere “Bolt-Ins” or obtaining any readily available canned PCM Tunes after consulting your local Speed Tuner Shops.

Then there is the lack of any creative space inside of the Engine Bays of the GMT360s that soon becomes the physical impediment to “shoe-horning” in any Turbo-Charger, Custom Turbo Exhaust and all of the ancillary gear necessary to pipe the Motor Oil into, out of and back down inside the Weird ‘Holland Tunnel’ Designed Crankcase. Practically everything that becomes useful in pursuit of this “Atlas In-Line Six Cylinder Unicorn” must be well thought out… and mostly… Made By Hand:


Every successful effort in this regard has been spearheaded with enormous determination, creativity and having a “Bottomless Wallet” to be able to get anywhere near the Horsepower and Torque that even the smallest 4.8L LS Engine, once lightly modified with ubiquitous Racing Parts available, can easily achieve for the average Daily Driver.

Generally, the Folks who make a Turbo-Charged Set-Up actually work will abandon the Wonderful GMT360s Chassis-Bodies and just drop it into the likes of the Boxy Ancient Studebaker Lark and-or an Old Boxy Checkers City Cab.

EMTech Motorsports Custom Manufactures unique LL8 Engine Rear Sump Oil Pans, Custom Fly Wheels and Atlas block to SBC/LS Transmission Adapters:

https://www.emtechmotorsports.com/Products.html

If you view this Video, supposedly, there is a ”Custom Performance Ported Engine Head and Camshafts” running inside of this NA Racing Engine being Tested on a Dyno… but when visiting their Web Site… there is no mention of any of these “Modified Bump Sticks” being available.

Even on a highly modified NA LL8 Engine… Stepping over the 6500 RPM Atlas Vortec 4200 Red-Line with an Engine sporting such LONG Camshafts and LONG Crankshaft is just asking for trouble… Think… ‘Rectangular Grenade’ here:


When Turbo-Charging the GM 4.2L Engine, Very Special Attention must be paid to the use of a particular Aftermarket Harmonic Balancer that requires a Woodruff Key Slot to be machined into the Nose of the Crankshaft. This helps to hold the HB rigidly to the Crankshaft once bolted on in order to attenuate the incredible amplitude increase in engine vibrations once it enters the realm above 6,500 RPM. The Crankshaft inside of this engine will begin to twist out of order along its length like a ‘Twizzler Stick’ at around 7,000 RPM risking catastrophic results to the Rotating Assembly.
 
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Reprise

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Maybe send a PM to @limequat -- he's done work with the LL8, and knows what's possible. He also has nice pricing on software tunes for our platform ($99)

As you can guess, there's limited support for the 4.2L inline six. The engine is solid, but not really known for being a race engine, unless you're willing to put a ton of time / $ into it (see: Limequat, above)

If you're serious about going racing, get an LS motor. Best support in the industry. "LS swap" should be in Merriam-Webster, by now. They fit in just about anything, and make gobs of power, relative to their size / weight.

If you want that LS in a GMT360, best bet (power / performance) is a Trailblazer SS -- that basically got a Vette LS2 motor as factory equipment. Next best (easiest to find) would be an Envoy Denali, which had the 5.3L as standard. But if you get one of these, don't envision getting a 4.2L and stuffing an LS in it. It's been done once or twice, but it's a royal PITA. Easier to start with one that had a V8, stock.
 

Mooseman

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Dec 4, 2011
25,262
Ottawa, ON
Look at it this way. Took the Saab to the track with its 5.3, 3.73 gears and mail order tune and it did 16 seconds in the 1/4 mile. It wouldn't even break traction on take off. It's a heavy truck and without some serious power (think TBSS), it ain't gonna move fast. Although you can probably make as much HP as a V8, the torque just isn't there to move all that weight.

But anything can be done with time, gearing, determination and MONEY, lots of MONEY. There are no off-the-shelf performance parts for this motor so the majority will be cu$tom made. There was some interest early in its life to mod it but because of its relatively short run of 7 years, the interest just isn't there anymore and was just a niche market at the time for those looking for something different or to revive the memory of inline 6's.
 

limequat

Member
Dec 8, 2011
520
Curious about the OP's drag racing project. A large BOF SUV is not conducive to drag racing regardless the power plant. If this is a swap, the options open up enormously.

Couldn't agree more with the wise insights already posted here. For a DD, get yourself a tune, exhaust, intake and be happy with what you have.

There are folks out there successfully racing the Atlas engines, but they've spent more than I spent on my house.

You want fun in a 360? Get an SS or Saab Aero.
You want fun in a swap? Get a turbo.
 

rchalmers3

Original poster
Member
Jul 11, 2020
207
Irmo, SC
While modifying the GM Atlas LL8 has been the passing fancy of many a GMT360 Owner-Mechanic, very few have been successful in doing so. The poor returns on the investment of Time, Energy and Money for the often paltry amount of additional Horse Power and Torque to be gained is generally the source of them suffering from the inevitable “Vortec 4200 Performance Build Buzz Kill”.
Although you can probably make as much HP as a V8, the torque just isn't there to move all that weight. But anything can be done with time, gearing, determination and MONEY, lots of MONEY. There are no off-the-shelf performance parts for this motor so the majority will be cu$tom made. There was some interest early in its life to mod it but because of its relatively short run of 7 years, the interest just isn't there anymore and was just a niche market at the time for those looking for something different or to revive the memory of inline 6's.
If you're serious about going racing, get an LS motor. Best support in the industry. "LS swap" should be in Merriam-Webster, by now. They fit in just about anything, and make gobs of power, relative to their size / weight.

Thank you gentlemen for your sage wisdom, observations and advise. However, I am thirsty, and I happen to have a rather large basket of lemons.

I request your continued support and encouragement to succeed in making this platform do a 13 second quarter mile. It's Ok if it is unpleasant to drive on the road: that sacrifice is already assumed, given the limits of the engines ability to produce power. I have the body, chassis and drive train all separated for their discrete modifications. The steering gear is converted to manual. The brakes are converted to manual, and the AC is deleted. I'm in the beginning process of removing body and chassis weight through metal mass reduction. I'm no engineer, but I have a pretty good idea on what to remove and what to leave. Pics of the current status can be provided if desired and bandwidth is not guarded!

I have zero race experience and wish to begin dispelling some of my fancy thoughts about this build. The first one is: 2wd or retain AWD? I found that 13 seconds is attainable with some combination of weight to power, say a 4400 pound car with 400hp getting to the ground. I assume 400hp can be put down with RWD only, with the correct tires and suspension. Ditching the front diff, axles and transfer case contributes considerably to the chassis diet. I would gladly accept the added complexity and challenge of AWD if there was a clear benefit to achieving the goal, but it seems unneccessary. What do you think?

@limequat you seem to be the guy to speak with, regarding a discussion of thoughtful mods to get the most out of the LL8 with minimal spending. I'm interested to know what you recommend for the LL8 stock engine, to prepare it for forced induction. The engine I am preparing is at the machine shop. It's a 2006 that needs dressing work. I anticipate it will require a hone to the original bore and standard bearings. What mods or materials can you recommend to prepare the stock engine increasing power output? My current intention is to use the OEM controller to operate the engine and transmission, unless there are limitations you know of that come with that choice.

Cheers to all,
Rick
 

Mooseman

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Dec 4, 2011
25,262
Ottawa, ON
I applaud you on your quest. Certainly doable if building a truly race only vehicle.

The TBSS came in both flavours with and without AWD. Power can certainly be put down through just two wheels, as I am currently doing in my Caprice 6.0L putting out 400hp. However you would be wise to find yourself a G86 limited slip diff either from a TBSS with 4.10 gears (ideal) or at the very least from a V8 TB or EXT or a V8 9-7x with the 8.6 ring gear. The G80 locker would not work well or would self destruct in short order.

Even if you were to retain the transfer case, the AWD in the 4x4 trucks suck. They only engage when there is rear wheel slip detected and would shift into 4x4. I call this system the "slip/bang" system. Same for the AWD trucks like the 9-7x. However, the TBSS uses the Torsen true full time AWD transfer case so that could be an option if you want to go that route.
 

rchalmers3

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Jul 11, 2020
207
Irmo, SC
However you would be wise to find yourself a G86 limited slip diff either from a TBSS with 4.10 gears (ideal) or at the very least from a V8 TB or EXT or a V8 9-7x with the 8.6 ring gear. The G80 locker would not work well or would self destruct in short order.

Thanks Mooseman, I appreciate your opinion on going 2wd. I recently looked for that G86 option on Ebay. It would have cost me $900 to purchase it and have it delivered. Finding it close to home would cut about $250 in shipping costs. Meanwhile, I have found there is a 4:10 gear set available for the 8" for about $300. I was thinking of going that route: fitting the ring gear to a case with welded spider and side gears. I have driven a locked rear axle on the road. It's unpleasant but doable. If I lighten the car as desired, perhaps the 8" can do the job and survive.
 

Mooseman

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Dec 4, 2011
25,262
Ottawa, ON
Check on car-part.com. The 8" would not likely survive with that kind of abuse. The 8.6 has a better chance. Check on Craigslist and FB Marketplace too. Sometimes people part out these trucks, even the TBSS.

At worse, grab a diff from a LWB or V8 and swap the carrier and gears. The 9-7x specifically had LS diffs so you could save on the carrier at least.
 
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Mooseman

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25,262
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LKQ also has a good search engine. For car-part, search for axle assy rear.
 
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mrrsm

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Okeedoke… And to assure you that I’ll be the Last Person to tell you “This Can NOT Be Done…” Here are a few more things to add to your “Mechanic’s Library” as you begin to consider what to do next:

For “470 HP’s Worth of Renewed Inspiration”… Start with THIS Article:

https://www.hotrod.com/articles/ccrp-1108-turbocharged-vortec-inline-six/

An Original Introduction to the “More Intimate Construction Details” of the GM Atlas LL8 I-6 4.2L Engine via GMTN:

http://www.superchevy.com/how-to/83758-chevrolet-vortec-4200-inline-six-engine/

The Major Engine Component Specifications and Additional Resources can be found HERE at GMTN with additional Links to related Performance Issues:

https://gmtnation.com/forums/threads/the-gm-vortec-ll8-links-and-specs-library.16738/

On the subject of the Need to Reduce the Compression Ratio when Turbo-Charging ANY Engine:

https://www.torquecars.com/tuning/lower-compression-ratio.php

On the subject of Component Fabrication for a Modified, Non-OEM Turbo-Charger Intake Manifold:

https://www.theturboforums.com/threads/vortec-4200-l6-turbo-build.372350/

Some General Engine Building Considerations that need to be accounted for when Turbo-Charging ANY Engine:

https://www.cartechbooks.com/techtips/how-to-build-your-engine-for-a-turbocharger/

A Decent Compression Ratio Calculator:

https://goodcalculators.com/compression-ratio-calculator/

A Boost vs. Compression Ratio Calculator:

https://www.rbracing-rsr.com/compression.htm

After Market Connecting Rods via THIS GMTN Thread:

https://gmtnation.com/forums/threads/after-market-hp-con-rods-for-gm-4-2l-ll8.16552/

Less Expensive Forged Connecting Rods Made by Molnar:


Ostensibly... AliBaba shows a POSSIBLE Outlet for a True BILLET Steel Crankshaft (102mm Stroke) that more recently has NOT been made available. You should know that while being fairly strong... The Nodular Cast Iron Stock GM LL8 Crankshaft will NEVER be as strong as using a Forged Steel Crankshaft, or in this case, a Crankshaft Machined from One Solid Steel Billet that will still be MUCH Stronger and more desirable in the pursuit of ANY High Performance Engine Building Application:

NLGROUP4200BILLETSTEELCRANK.jpg

You should inquire HERE for this possibility... and prepare to have to Spend a BOAT LOAD of MONEY!!!


VORTEC4200BILLETSTEELCRANKSHAFT1.jpg
 

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rchalmers3

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Jul 11, 2020
207
Irmo, SC
Okeedoke… And to assure you that I’ll be the Last Person to tell you “This Can NOT Be Done…” Here are a few more things to add to your “Mechanic’s Library” as you begin to consider what to do next:

Thank you sir, I appreciate your willingness to contribute to this mission. I am sure some of the leads you have provided in this thread will become of use as I progress, especially when I get to the power adding phase of the engine build. I have spent most of my life restoring and maintaining vehicles. This project is quite the contrast, especially as I work on the weight elimination phase of improving performance!

Rick
 
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mrrsm

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Bump Post #11... I just added MORE information about some Less Expensive Forged Con-Rods...and ... The possibility for obtaining a Vortec 4200 Crankshaft Machined from One, Solid Steel Billet.

And if you want to Improve the Strength and Reliability of the LL8 Vortec Engine... This link brings up an Article I posted on" How to Replace the Aluminum Engine Block Mains Bolt Holes Using The TIME-SERT System" to accomplish this task.

There is also More Information to be found here about the use of a Special After-Market Harmonic Balancer more suitable for Turbo-Charging the LL8 Engine here, too:


EDIT: 11/07/2020 (A VERY Good Day!!!!)

This is the Follow On Article I documented for "How to Replace the Engine Block Head Bolt Holes Using The TIME-SERT System".

 
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limequat

Member
Dec 8, 2011
520
13's should be quite doable. Consider the SS had 400 HP, 4:10 gears and did 14s.
Couldn't agree more with @Mooseman 's recommendation to the the SS gears in 2WD. Bang-for-your-buck, this probably the single best thing you can do.
IMHO, the weak spot of the 4.2 is not the rods or pistons, but the bearings. I don't believe there is an aftermarket solution, but maybe you can figure something out. Otherwise, port the head, boost to 15 psi and you'll be at 600 crank HP.
 

Mooseman

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Dec 4, 2011
25,262
Ottawa, ON
And if increasing to that much HP, you'll need to beef up the cooling system as the stock radiator is woefully inadequate. Some have been having trouble keeping it cool while towing even with the mechanical clutch fan. I've seen some adapt a Dodge aluminum radiator to use with efans however I've found this one which looks like a good deal. The biggest thing that prevented using efans was the radiator.

 

rchalmers3

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Jul 11, 2020
207
Irmo, SC
This is engine 1.0 It's a 2006 engine with the 7x crank reluctor. It has been refreshed with standard bearings and rings, however I opened the ring end gaps in anticipation of adding forced induction. IMG_0223.jpgIMG_0224.jpg
I am deleting power steering and A/C, so I reworked the tensioner to pull on the belt vs push it into tension. The other mods are deletion of the heater hose pipe nipples and fitment of AN fittings to the valve cover for a catch can, and another AN fitting to the oil pan for turbo oil drain back. My current plan is to get it running first in stock form, before modding it further.

Engine 2.0 is in the on deck circle. It's a 2008 with the 58x crank reluctor. However, the 2.0 version may become the 1.0 version, as I understand the E67 controller for the 2008 engine is the one to work with when trying to make power adders function.....

Once I clear up some final bits on engine 1.0, I'll disassemble the 2008 engine and send it out for rebuilding.

Rick
 
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mrrsm

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Just an FYI… A little earlier this morning… @xavierny25 posted a Link to a YT Video over in another Thread showing the Owner-Driver of the “Studebaker LL8” Race Car Owner Cutting a 9 Second Quarter Mile at the Lights while running his OTHER Turbo-Charged LL8 Vortec 4200 Ford Fairmont that makes 441 HP on the Dyno.


So I poked around over on YouTube and watched these Three OTHER related Videos that WILL seriously interest you to No End. The Biggest Revelation here is that THIS time... the Vortec Builder used the Stock Intake Manifold with a Highly Modified Throttle Body Set Up and a Completely Stock Used GM 4.2L Motor to achieve these remarkable results. Thus, his work here may open up even more opportunities for you to get Under The Skin of His Build and see if you can do likewise with yours...and perhaps having to invest a whole lot less work and effort.

In particular is the information he leaks out while trying to *Winkle* out More HP and discusses his Spark Timing and Boost settings along with trying out a novel idea for manipulating the PWM of the CPAS Solenoid VVT-Cam Phaser to get better gains with Horse Power and Torque. Be sure to say a sincere “Thank You” to @xavierny25 for letting THIS 'Cat Out of The Bag!'



 

rchalmers3

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Jul 11, 2020
207
Irmo, SC
Thanks @MRRSM I have watched Calvin's shenanigans with the LL8. His skill set, tools and the experience pool surrounding him are to be admired. I'm pleased to not have Calvin's challenges of the need to adapt the LL8 into neither another vehicle nor to another transmission. To reference an earlier metaphor I stated, I'm trying to get lemonade from lemons. He's already making batches of lemon hooch.

With no experience in this specific engine, racing, or tuning power adders, I'm on a slow, steep learning curve. I'm currently at a crossroad: Do I set the 2006 engine aside, or continue to prep it for my purpose. If the 2008 engine and it's E67 controller are the optimal starting point, then maybe I should put my time and precious resource into that motor.

I could fit the 2006 engine into a car needing an engine, then flip it to create additional funds for the project. I have the time, skills and resources to purchase and flip a car, so I am not at a loss. I just need more and a deeper understanding of how to get the most power out of this engine.

Any suggestions on where to find online discussions of folks modifying and testing these engines?

Rick
 
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mrrsm

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If you have not as yet visited this site... Stop in, Join and perhaps Poke Around with "The Mighty Car Mods Builds" and see what you can find...


The Break Point here with the GM 4.2L Engine will always be that with its Rectangular "Boxy Waist Line" comes the limitations of "Where to Hide The Salami?" of the Turbocharger and Exhaust Headers-Piping. And of course, the other Elephant in The Room being the "Mysterious P10 PCM" acting as a common barrier, without having familiar HP-Tuners program-Calibrations widely available and tested for improved Horsepower and Torque.

Still... What those Videos DO prove is this: "There is always MORE than One Way to Skin a Cat". So far... the lack of having any proven way to create over 500 to 1,000 HP presents slender inducements for most Hot Rodders to want to spend their HEBs (Hard Earned Bucks) on using ANYTHING other than an LS Engine to get EXACTLY what they want.

What WOULD be nice to have though for the Two Wheel Drive GMT360 Variants would be a Complete Tubular Front End ...Built from the Firewall OUT that could also provide us with Removable Engine Wheel Wells and allow for unbolting-bolting of a Well Designed 4130 Chrome-Moly Steel Cage. That way, you could R&R the Engine and Transmission straight out through the front of the vehicle in a matter of just a few hours. So much more could be accomplished strictly based upon us all having improved Engine and Transmission Access!

Damn You, Ron Kociba!!!

Oh Well... Perhaps in an Alternative GMT360 Universe.
 
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rchalmers3

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Jul 11, 2020
207
Irmo, SC
What WOULD be nice to have though for the Two Wheel Drive GMT360 Variants would be a Complete Tubular Front End ...Built from the Firewall OUT that could also provide us with Removable Engine Wheel Wells and allow for unbolting-bolting of a Well Designed 4130 Chrome-Moly Steel Cage. That way, you could R&R the Engine and Transmission straight out through the front of the vehicle in a matter of just a few hours. So much more could be accomplished strictly based upon us all having improved Engine and Transmission Access!

As much as I'd like, I'm not capable of building a tube frame vehicle, but I did do quite a bit of carving on the frame I salvaged from the rolled 2008 car. This week I set the body on the frame for the first of probably many times:
IMG_0240.jpg
I did bob the frame a bit, and I intend to work up a removable clip (using the steel fenders and hood) that lifts or tilts for inspection and maintenance work, but also removes easily and completely for engine removal. I have a few ideas to consider.
IMG_0242.jpg
I opened up the cowl area above the engine. I hope to make routine spark plug maintenance and inspection a little easier. Look closely and you can see I have performed a manual brake modification and the steering is converted to manual.

I am performing other modifications to the body, especially with regard to weight reduction. I'm really good at taking things out, but find it to be time consuming and costly to put items in! I may make mistakes from cutting corners and or inexperience, but I'll continue to share the progress as it occurs.
Rick
 
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rchalmers3

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Irmo, SC
Then there is the lack of any creative space inside of the Engine Bays of the GMT360s that soon becomes the physical impediment to “shoe-horning” in any Turbo-Charger, Custom Turbo Exhaust and all of the ancillary gear necessary to pipe the Motor Oil into, out of and back down inside the Weird ‘Holland Tunnel’ Designed Crankcase. Practically everything that becomes useful in pursuit of this “Atlas In-Line Six Cylinder Unicorn” must be well thought out… and mostly… Made By Hand:

Speaking of the oil pan, I took a quick look at the design, and I believe there may be an engineered solution to oil slosh, leading to oil starvation and lunching of the rod bearings.

I found there are five sets of stands cast into the pan, presumably for attaching a pair of baffle sheets, in front of and behind the axle passage. I measured the height of the stands in relation to the level that the dipstick protrudes down into the pan and found a positive correlation. This is all speculation on my part, as I have not seen any such animal thus far in my journeys!

Here I have an assembled engine turned upside down with the pan removed. The wood blocks sitting on the block rails measure 3 5/8" which is very nearly half stick.
IMG_0227.jpg
The pan has 5 sets of stands cast in at nearly the same height.
IMG_0228.jpg
I thought I'd fudge it a bit, being "infinitely" smarter than the engineers, and I cut the rear baffle stands down to what would be the low level height on the oil stick. I then drilled and tapped them to 6x1.0.
IMG_0229.jpg
Here, I cut and formed a piece of Home Depot 22 gauge metal to block the oil from sloshing rearwards, while still being lower than the low level oil height.
IMG_0230.jpg
IMG_0231.jpg
With the oil pan set level, my attempt at fabricating the baffle should be "submerged" when the oil level is at an indicated "full". My thinking is that is a good height for easily recharging the sump (without additional perforations in the baffle), while retaining sufficient oil for acceleration. What are your thoughts? I'm also considering adding an external accumulator to replenish oil under pressure as a safety precaution.
Rick
 

mrrsm

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If it will help... Here are some images I took while photo documenting what the GM OEM Oil Pan used to look like. I think you should be able to scale these images up to the proper sizing and approach the Drill Out Locations necessary to accommodate the Oil Pick Up Tube Entry position without allowing it to make direct contact with the Front Plate. And also... for the Rear Plate comes the need to know where to Drill Out the Aerate Relief Hole(s) and the access Hole for the Dip Stick to be able to reach all the way down to the bottom of the Crank Case.

Another Consideration involves knowing where to place the Return Oil for any Drill-Out TIG Welded AN Oil Line Port for the Turbo-Charger Return Oil Line in order to reduce the chances for creating swirling eddies and turbulence that might Whip Up and Aerate the returning Hot Oil and cause an accidental drop in Oil Pressure after inducing a constant stream of air bubbles around the Oil Pick Up Tube.

BEWARE: The Gerotor Oil Pump in THIS LL8 Engine is capable of moving over 11 Gallons of Motor Oil through the Oiling Circuit ...Per Minute! So there is the need to adjust the width for the Perimeter Side Clearances on those Two Baffle Plates, inviting the rapid flow of the unpressurized oil gravity feeding from above.

The Two Plates should be measured and shaped correctly in order to allow the Oil that descends through the Side Trapezoid Block Channels as Over-Flow Oil coming down from the Engine Head ***. You'll want to get that Oil right back down into the bottom of Crankcase Oil Pan Reservoir Chamber As Fast As Possible*** in order to avoid Oil Pick-Up Tube Starvation at Higher RPM levels during "Line Start and Shift Lurching" when at speed..

43350774572_69956e70d0_c.jpg29528233298_c43d9153be_c.jpg43350774792_c2212ccaea_c.jpg29528233138_330f5826d5_c.jpg29528232918_5a6287062b_c.jpg29528232688_efb5495dc3_c.jpg43350774332_433de57a48_c.jpg

One Last Concern...

The Shape of the Channels that drop down at two points inside of the lower Oil Pan may be NECESSARY for the improvement of Laminar Oil Flow moving upwards and inside of the Oil Pick Up Tube.

If you alter either of those two locations, in the absence of having the Two Factory OEM Baffle Plates properly installed, there may be an unexpected, paradoxical lack of improvement in controlling the Oil Sloshing and inadvertently wind up diminishing or defeating the ability of the Oil Pump Pick Up Tube to function properly.

Your clever adaptation may effectively alter that expected Engineered Oil Flow Path in unpredictable ways that ultimately may not deliver the Oil Slosh Control Benefit you are seeking.

NOTE:

*** I am NOT Recommending that you do ANY of the Actions that this Mechanic suffering from "Engine Building OCD" engages in here... I just want to make you aware that "Oil Repellent Paint" like Eastwood's "GLYPTAL 1201" DOES Exist and that regardless of the absurd-extreme amount of Surface Preparations necessary for its Application to Aluminum Engine Blocks, Engine Heads and Oil Pans Surfaces... THIS STUFF REALLY WORKS to Improve the Speed at which Engine Oil is able to Return to the Bottom of the Oil Reservoir***


EASTWOODGLYPTALPAINT.jpg


Engine Head:


Engine Block:

 
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efi-diy

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Dec 9, 2011
32
I don't come in here very often - but this thread has some useful tidbits. If your going to lean hard on the 4200 - the external oil feed to the main oil gallery is good insurance.
Also 1 person (not me) on the 4200 facebook page is trying get a min order for billet cam blanks together.
 

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mrrsm

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Roger THAT. I Agree... as long as the External Source Accumulator Pressures does NOT exceed the Oil Pressure coming through from the Gerotor Oil Pump. The Oil Pressure vs. Crankshaft Main Bearing Clearance Tolerances are very critical to get right if you are pushing this Engine to rotate at or above 6,500 RPM. If you venture ABOVE that Margin... even with using the Modified (Woodruff Keyed) Harmonic Balancer... The Excessive induced Vibrations of Longitudinal Amplitude entering the Crankshaft will soon Tear the Motor Apart.

GMLL8OILFLOWPATH.jpegOILFILTERMANIFOLD.jpg
 

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mrrsm

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And...FWIW Rick... The 2002 GM LL8 Oil Pans might start getting as "Scarce as Hen's Teeth"... and since THIS One HAS the Dual OEM Oil Baffle Plates installed and with it being available for just under $60.00,You just might want to 'Grab It while the Grabbing is Still GOOD' over on eBay:


s-l500.jpgs-l500B.jpg

If you get it... Just lather up some Evapo-Rust Liquid Gel with a Paint Brush and also using a Rag attached to a Coat Hanger soaked in this Goo in order to apply it underneath the Plates. After just a few Hours of Contact Soak... Hose it Out with some Hot Water and then Spray the Plates down right away with Water-Displacing WD-40 and it will bring back those Mild Steel Baffle Plates to a Nice and Shiny, Rust-Free Condition again:



EVAPORUSTGEL.jpgEVAPORUSTGEL1.jpgEVAPORUSTGEL2.jpg
 
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rchalmers3

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Irmo, SC
Thanks guys, this discussion is giving me pause to mull over the various considerations mentioned. Knowing the oil pan baffles were deleted after the first year, you gotta wonder why they did that, especially since this motor struggles with oiling. Makes me wonder if the 2002 engines outlasted the rest, given the slosh control they alone sported.

I have until now successfully resisted any social media, but upon learning there is a forum based on the 4200, I have activated a Facebook account and am receiving tutorials from the spousal unit on how to navigate the application. Hopefully when I get access to additional wisdom, my mistakes will be at a higher level.

Rick
 

mrrsm

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Rick... FWIW...

You could try an Experiment ... By setting the Oil Pans level on a Wheeled Cart or in the bottom of a Wheel Barrow and after filling them only as far as the recommended 7 Quarts of Cheap Organic 5W30 Motor Oil ... Roll them around while making the motions emulating Rapid Starts and Sudden Stops and observe the DIFFERENCES between the two Oil Pan Layouts are... With and Without the Oil Control Baffles.

The rolling motions don't have to be Too Drastic...
just sudden enough to create the Fluid Dynamics that happen all the time during Starts and Stops. Doing this for each Oil Pan in sequence while you observe their 'Slosh Factor Behaviors' might eliminate any guess work about which one to choose.

This might seem like it will be VERY "Messy" But I've successfully used a 1/2" X 12" x 30"+ Piece of Aluminum Plate on an inverted LL8 Engine Block for other TIME-SERT Repair Purposes. So it prompted me to think that You could probably easily duplicate this very same idea But instead, use a comparable sized Piece of Clear Plastic or Acrylic as a "Clear Cover" to Keep the Oil INSIDE of the Oil Pan while still being able to conduct your Experiments and observe everything that dynamically happens therein.

After laying the Solid Clear Plastic Template over the Flat Upper Flange of the Oil Pan, just use a Red Magic Marker to identify the required (6) Holes (2 @ the Front, 2 @ the Middle Sides and 2 @ the Back Positions) and Drill them out of the Plastic Sheet where they match up to the matching holes in the Crankcase-Oil Pan Flange. You'll also want to Drill out a Convenient Oil Fill Port through the Plastic Sheet that can be easily sealed up tight with a few strips of Duct Tape after using Brake-Kleen to wipe down the adjacent areas.

Next ... Run a Bead of light Silicone Rubber Sealant around the Oil Pan Flange Perimeter and then use the (6) Fastener Nut-Bolt-Washer Combos to Gently Hold Down the Clear Covering. This way, you can avoid Making One Helluva Mess while also getting to study just exactly HOW the Sloshing occurs in BOTH Test Cases. I think that for the amount of effort needed to make this happen, it might reveal more of what you want to know empirically than one might imagine is possible. :>)

EDIT 12/09/2020:

*Bump* back to Post #24 for MORE Information...
 
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rchalmers3

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I don't come in here very often - but this thread has some useful tidbits. If your going to lean hard on the 4200 - the external oil feed to the main oil gallery is good insurance.
Also 1 person (not me) on the 4200 facebook page is trying get a min order for billet cam blanks together.
@efi-diy did you intend to add a link to another thread? I appreciate any opportunity to learn about what keeps these engines together. Thanks bud,
Rick
 
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rchalmers3

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You could try an Experiment ...

Great suggestions, thank you for describing a doable test for gathering more understanding of the apparent issue. I certainly see the benefit of the testing you mention. For now I will explore the collective wisdom of experience that is available. I'd like to know if someone has made the front sump design survive in drag racing conditions, and what mods did perform to achieve their success.

Rick
 

mrrsm

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The Billet Fabrication, Inc. company comes to mind... You could try giving them a call at (509)-568-0428 or send them an Email at billetfabrication@hotmail.com. If anybody knows how to build Wet and Dry Sump Billet Aluminum Oil Pans for a LOT of Racing Applications... They Do.

 
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efi-diy

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Dec 9, 2011
32
Roger THAT. I Agree... as long as the External Source Accumulator Pressures does NOT exceed the Oil Pressure coming through from the Gerotor Oil Pump. The Oil Pressure vs. Crankshaft Main Bearing Clearance Tolerances are very critical to get right if you are pushing this Engine to rotate at or above 6,500 RPM. If you venture ABOVE that Margin... even with using the Modified (Woodruff Keyed) Harmonic Balancer... The Excessive induced Vibrations of Longitudinal Amplitude entering the Crankshaft will soon Tear the Motor Apart.

View attachment 99016View attachment 99017
If you open the rod bearing clearances to 0.0021/0.0023" and run the BHJ damper + external oil feed - much better chance to get the engine to live.
 

rchalmers3

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Irmo, SC
Thread revival time!

Now that I have the engine test platform completed: https://gmtnation.com/forums/threads/ll8-engine-test-platform-project.21715/#post-612919 and have a running, freshened 2006 engine (with 7x crank reluctor and P12 ECM) that can be used to get me started in racing, I will move on to the body preparation and chassis work.

The chassis is nearly complete. In addition to cutting out much of the inner box channel metal and deleting numerous weight adding brackets and features, I have fitted 4;11 gears into a larger differential sourced from the Rainier version, and have stripped out the parking brake mechanisms and trimmed the caliper mounts to an absolute minimum. As mentioned previously in this thread, I have converted to manual brakes and steering.

I have a stock 2008 transmission I could run as is, or I may crack it open and freshen it if needed??? Expenditures are vital: There is no endless pit of money to draw from, so it makes sense to run a stock transmission behind a stock engine, at least to put the car into operation!

The remaining chassis work entails selecting springs and shocks to set the ride height and reaction to power. Those component selections will have to come later, as they will be determined by the measurement of the lightened vehicle weight. Finally, I'll need to figure out a slick new method of attachment/detachment for the hood, grill and outer fenders! That should wrap up the chassis mods.

The body mount assemblies are surprisingly heavy, prolly 10 pounds each! I have eliminated a pair of mounts, back where the rear passenger seat belts coupled to the body. I will seek to lighten the remaining 8 mounts by using polyurethane pucks and lighter hardware.

On to the body mods. I am in the process of carving weight out of the robust GMT360 body.
The 5 doors are currently on the butchers block. I started with the rear doors, as they presented the clearest opportunity to pare them to a minimum. I have gutted them, reverted them to one piece glass, and will screw in 1/8" Lexan into a new mounting surface I welded in that will (hopefully) come out flush with the window framing. I just received the Lexan material and will post pictures of the first rear door when it's completed, if y'all want to see what your car could look like if you decided to carve it out like a pumpkin!

I'll tackle the rear hatch after I complete the rear doors. The hatch is a heavy and complicated structure, with the glass and hatch being independently operable. I'm gonna cut it waaaaay down to just a hatch operation with the same sized glass made immobile. The tools I'm using are an air driven reciprocating saw, metal bender and welder. I'm having some good times!

I'm saving the front doors for last. I want to simplify them as well, but am ambivalent about retaining the power operation and/or converting the glass to plastic. If you have or have seen any clever ideas on making lightweight operable roll up/down windows, please share!

I need to consider a roll cage. The dash (and entire interior) is gutted, so that huge, cast aluminum structure behind the plastic dash is gonzarella. I need a replacement hard structure to support the steering, and some beef to prevent excessive wadding of the body in case of roll over. I do not have a tubing bender, and don't have the coin for a single purpose tool. JEGS offers various weld up kits for other vehicle makes and models that may be suitable for adaptation to the GMT360 platform. They offer a 4 point kit for the GM C series truck of the same year model. I happen to have a 2005 GMC 1/2 ton Sierra that I can use for reference and measuring, so that will be my starting point in the search for a cage kit. I'll let you know what I find.

I will be purchasing a TIG welder for assembling the roll cage, and for the numerous aluminum welding projects that present themselves along the way. I'm looking to purchase a TIG set-up that is mid-priced, say $750 in total. If you guys have any recommendations, please post up.

Thank you for your interest and encouragement as I progress. I look forward to your questions or comments.

Rick
 

Mooseman

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Dec 4, 2011
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Will be very interesting to see what this engine is capable of with that slimmed down body.
 
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rchalmers3

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Jul 11, 2020
207
Irmo, SC
Springtime thread revival!

I have ordered a 2 post hoist to allow me the ability to separate the body and frame as needed for the further construction of the race car. The hoist should arrive at the end of April and it should take only a day or so to assemble and set up.

Also I sourced an Eastwood TIG welder and have completed the assembly of a welding unit. My first project will be to weld up a simple down pipe from the stock exhaust manifold through the frame, exiting behind the pasenger front wheel. After that I'll undertake to welding aluminum AN fitting bungs to a block and valve cover. Then onto a rool cage and seat mounts, and so on...

There has not been much progress on the chassis nor body, as I have been busy with the completion of the engine test platform as well as other unrelated household projects. However, I did complete the lightening of the rear passenger doors and have fitted fixed Lexan glass. I am quite pleased with the results. They are not show quality, but have about 30 lbs weight reduction each.

I am currently building an oven to drape form the windshield and rear glass pieces. More on that as I progress and achieve some results!

Regarding the body mounts, I manufactured plastic mounts that lower the body to the frame about 3/4" over stock mounts, plus provide about 10lbs total weight savings. I may purchase shorter bolts for replacing the stock bolts and save an additional lb. Dunno if that is worth it or not....

This energetic guy got a bit carried away cutting weight out of the rear hatch. It is a very complicated piece to attempt weight reduction on. While attempting to eliminate the complexity of the hatch's movable glass, I cut out too much of the inside and ruined the hatch seal to the body seal gasket area. I'll need to toss out this hatch and try again with another one. I have another hatch here, but it's a Purplish/Maroon color. I may visit the bone yard to see if there is a hatch I can buy cheap in order to maintain the body color.

I don't have as many projects at the moment, so I'm hoping to update this thread more often. I'll post progress images if there is any interest.

Cheers to all,
Rick
 

efi-diy

Member
Dec 9, 2011
32
This is engine 1.0 It's a 2006 engine with the 7x crank reluctor. It has been refreshed with standard bearings and rings, however I opened the ring end gaps in anticipation of adding forced induction. View attachment 98757View attachment 98758
I am deleting power steering and A/C, so I reworked the tensioner to pull on the belt vs push it into tension. The other mods are deletion of the heater hose pipe nipples and fitment of AN fittings to the valve cover for a catch can, and another AN fitting to the oil pan for turbo oil drain back. My current plan is to get it running first in stock form, before modding it further.

Engine 2.0 is in the on deck circle. It's a 2008 with the 58x crank reluctor. However, the 2.0 version may become the 1.0 version, as I understand the E67 controller for the 2008 engine is the one to work with when trying to make power adders function.....

Once I clear up some final bits on engine 1.0, I'll disassemble the 2008 engine and send it out for rebuilding.

Rick


The 06 up cranks are not fully counterweighted and cause a dynamic loading issue on the rod bearings (beats the piss out of the rod bearing)- I know this first hand. Once I changed to an 05 crank the problem went away. The 05 crank can be machined to accept the 58t tone ring from a 08/09 crank. This needs to be done by a competent machinist.
 

rchalmers3

Original poster
Member
Jul 11, 2020
207
Irmo, SC
The 06 up cranks are not fully counterweighted and cause a dynamic loading issue on the rod bearings (beats the piss out of the rod bearing)- I know this first hand. Once I changed to an 05 crank the problem went away. The 05 crank can be machined to accept the 58t tone ring from a 08/09 crank. This needs to be done by a competent machinist.
Cheers Marc,

The 2006 served to familiarize myself with the engine and is being used to test fit modifications for racing. By the time I have the car ready, engine 2.0 will be a better candidate.

I have assembled all the pieces for the version 2.0 short block. It is a 2005 crank swapped into a 2008 engine. This engine will run the 8000 RPM balancer.
The 2008 head is at a machine shop being studied for improvements. With these pieces, I’ll realize the better balancing you mention, plus I will be able to continue to utilize the services of @Lime-Swap for tuning.

My first goal is to get the car running down the track reliably and with competence on these first engines. Then I can start to educate myself on the science of making power.
Thank you for your interest and comments, I appreciate your contributions here.

Rick
 
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