Engine mount replacement

CDJuda

Original poster
Member
Dec 28, 2012
221
I'm wanting my vehicle to feel a little bit more responsive, So I'm gonna be swapping out the engine mounts for starts. I'm wanting some really stiff ones, anybody have any recommendations for where can I buy them and what brand to buy from?
All feedback is greatly appreciated

-Chase
 

The_Roadie

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Nov 19, 2011
9,957
Portland, OR
Wrong solution. Only change mounts for the 10 Hz vibration problem. A tune helps responsiveness, whatever that means.
 

CDJuda

Original poster
Member
Dec 28, 2012
221
I'm not claiming to be an expert, but a friend described it as " when you hit the throttle with softer engine mounts, the engine has more room to move around in the bay when first hitting the gas. The engine will torque itself into a certain direction before all the power is applied, with stiffer engine mounts this little movement is eliminated. " I'm just wanting my TB to have a rouger feel to it, I'm thinking about getting stiffer suspension as well. Idk again I'm not an expert but if you have recomendations I'm all ears. :crazy:
 

jimmyjam

Member
Nov 18, 2011
1,634
i guess you could fab some solid mounts if you really wanted to, I can't imagine why you would.

I don't think anyone would make stiffer engine or body mounts as I doubt there is any market for them at all. might want to check energy suspension
 

Mark20

Member
Dec 6, 2011
1,630
If you have not had the torque management of the engine computer dialed back then there is a maximum rate the engine will be allowed to spin up. As I understand it, this was done to protect the transmission when towing a large load. I don't think stiffer engine mounts will make that much of a difference in getting power to the wheels.

I've had my engine computer tuned by PCM4Less and they've removed about 80% (their words) of the torque management. The Voy gets up and goes now. Again, I don't think stiffer engine mounts would make any significant difference in power to the wheels and would make the Voy feel that much more harsher. And by the engine being able to relieve some of the torque into a "soft" mount, it may be protecting itself so you don't end up with problems elsewhere in it.
 

The_Roadie

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Nov 19, 2011
9,957
Portland, OR
CDJuda said:
... a friend described it ...
...without understanding the science. Let's say a motor mount allowed the engine to rotate as much as 5 degrees. (I'm sure it's closer to 0.5 degrees). When you mash the throttle at idle, you're at 600 RPM or ten revs per second. 100 milliseconds per rev. 5 degrees is 1.4 % of a revolution, or 1.4 milliseconds worth of delay. It's coincidentally about the same time it takes your foot (which is in the middle of stomping on the pedal) to move 1".

Seriously, torque management in the PCM is giving you MUCH MORE delay, especially in opening the butterfly valve in the throttle body. Get a tune and remove a lot of torque management and you may start to fool yourself into thinking you bought a turbo Miata instead of a 5000 pound SUV with a different intended mission in life.

"Rough" and "responsiveness" are still foreign terms for most owners. It's a heavy SUV. Body on frame. Love the one you're with. :wink:
 
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CDJuda

Original poster
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Dec 28, 2012
221
Is a pcm4less the best place to get a tune? How much does it cost and will it affect my winter driving? We get a lot of snow here in Kansas City during the winter.
 

Mark20

Member
Dec 6, 2011
1,630
They are really the only one talked about hear and on the old site. They have worked out a very good tune that they will customize to your needs. (Still need to tow a lot, they'll leave more torque management in). My Voy is much more fun to drive now and punching the accelerator is no longer a meaningless task.

What torque management does is limit how fast the engine responds to the accelerator. I can't find it now but I did see a video demonstration. The tech was banging the accelerator up and down with his hand and the butterfly valve was taking its sweet time opening & closing with torque management in. With TM reduced, the butterfly was keeping up with the accelerator. If you are able to pull your ECM and leave your TB/Voy sitting there, once they program it and send it back you'll be good to go right after you pop it in. No CASE relearn. I had the luxury of doing this.
 

CDJuda

Original poster
Member
Dec 28, 2012
221

CDJuda

Original poster
Member
Dec 28, 2012
221
Nevermind! Ended up finding it, for anyone that's ha this service done before. Any idea on what the turn around time is? It's my daily driver so I just wanted to get an idea. :thumbsup:
 

jimmyjam

Member
Nov 18, 2011
1,634
CDJuda said:
Nevermind! Ended up finding it, for anyone that's ha this service done before. Any idea on what the turn around time is? It's my daily driver so I just wanted to get an idea. :thumbsup:

Just think of what questions you have and give them a call. they're friendly folks
 

Mark20

Member
Dec 6, 2011
1,630
Very friendly fokes. Two or three rounds of email before I ordered.

Total time from Philly to them and back was ~4 days. The flash and send out the ones when the TB/Voy is dead without the ECM. They do have an ECM loaner program.
 

CDJuda

Original poster
Member
Dec 28, 2012
221
Is there a thread on how to take the PCM out? I might send this thing in next week if It doesn't take more than an hour to get out.
 

Envoy_04

Member
Jul 1, 2013
749
CDJuda said:
Is there a thread on how to take the PCM out? I might send this thing in next week if It doesn't take more than an hour to get out.

The search function is your friend here. There is in fact a write up on this process in the articles section, I'll link it below.

GMTNation - Installing A PCM (4.2L I6)

The actual process is easy, the security relearn, if you have to do it, takes time, but the PCM comes with very good instructions that are easy to follow, just do exactly as they say.
 

Mark20

Member
Dec 6, 2011
1,630
Though the length of the control cables to the ECM pretty much dictate where each one of the three go, it doesn't hurt to take a picture of them ahead of time. Leave the gaskets on the control cable connectors so they do not get lost.

Pulling the ECM is as easy as undoing the bolts holding the cable connectors on and then the four bolts holding the ECM to the engine block. I don't remember the socket size you need and, IIRC, they are two different sizes.

You'll spend more time boxing the ECU to ship than taking it out and putting it in.
 

CDJuda

Original poster
Member
Dec 28, 2012
221
the roadie said:
...without understanding the science. Let's say a motor mount allowed the engine to rotate as much as 5 degrees. (I'm sure it's closer to 0.5 degrees). When you mash the throttle at idle, you're at 600 RPM or ten revs per second. 100 milliseconds per rev. 5 degrees is 1.4 % of a revolution, or 1.4 milliseconds worth of delay. It's coincidentally about the same time it takes your foot (which is in the middle of stomping on the pedal) to move 1".

Seriously, torque management in the PCM is giving you MUCH MORE delay, especially in opening the butterfly valve in the throttle body. Get a tune and remove a lot of torque management and you may start to fool yourself into thinking you bought a turbo Miata instead of a 5000 pound SUV with a different intended mission in life.

"Rough" and "responsiveness" are still foreign terms for most owners. It's a heavy SUV. Body on frame. Love the one you're with. :wink:

Ran this by a friend the other day, the part where you say "It's coincidentally about the same time it takes your foot (which is in the middle of stomping on the pedal) to move 1"." The engine wouldn't start rotating or moving until you hit the pedal anyway right? So it would make a difference; a small difference but a difference none the less.

I just ordered my suspension kit from Norcal, or I've transferred my funds anyway. After lowering it and re-doing the exhaust, which will include a set of kooks headers and possibly changing the muffler type and location. I'll probably get my PCM tune. I just thought I would come back to the post and let everyone know what's going on. :smile:
 

The_Roadie

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Nov 19, 2011
9,957
Portland, OR
CDJuda said:
Ran this by a friend the other day, the part where you say "It's coincidentally about the same time it takes your foot (which is in the middle of stomping on the pedal) to move 1". The engine wouldn't start rotating or moving until you hit the pedal anyway right? So it would make a difference; a small difference but a difference none the less.
I should have said: It makes no distinguishable difference in the real world compared to human reaction time and other mechanical factors. :wink:

To put it in perspective, human reaction time to a visual trigger is around 200mS. The throttle body butterfly valve motor is rate-limited, and I haven't done the math on that, but I bet there's another 100 mS. And the biggest delay is in the fuel getting from the injectors through the intake manifold and valves into the combustion chambers. The fastest that could happen is one rev of the crankshaft, or 100 mS. Then you need a compression cycle and spark plug ignition - another 100mS at 600 RPM idle. Then the power has to flow through the transmission and torque converter - filled with slushy fluid. Thinking about the entire chain of events in the hundreds of milliseconds, folks who think motor mounts that resist engine rotation would do better to optimize other parts of the process.

I was going to say 1.4 mS is nothing to sneeze at, but sneezing can take 300-500 mS.

You could make a (relatively) huger difference by using EFILive or HPTuners to change your idle RPM to 900. That could improve your launch time by 50-100 mS assuming you're at idle at a stop light and not revving up with the brakes on. At significant cost in fuel economy, etc. For some reason I don't hear of people tuning their PCMs to do this. (Maybe nobody thought of it?) :confused:
 

CDJuda

Original poster
Member
Dec 28, 2012
221
the roadie said:
I should have said: It makes no distinguishable difference in the real world compared to human reaction time and other mechanical factors. :wink:

To put it in perspective, human reaction time to a visual trigger is around 200mS. The throttle body butterfly valve motor is rate-limited, and I haven't done the math on that, but I bet there's another 100 mS. And the biggest delay is in the fuel getting from the injectors through the intake manifold and valves into the combustion chambers. The fastest that could happen is one rev of the crankshaft, or 100 mS. Then you need a compression cycle and spark plug ignition - another 100mS at 600 RPM idle. Then the power has to flow through the transmission and torque converter - filled with slushy fluid. Thinking about the entire chain of events in the hundreds of milliseconds, folks who think motor mounts that resist engine rotation would do better to optimize other parts of the process.

I was going to say 1.4 mS is nothing to sneeze at, but sneezing can take 300-500 mS.

You could make a (relatively) huger difference by using EFILive or HPTuners to change your idle RPM to 900. That could improve your launch time by 50-100 mS assuming you're at idle at a stop light and not revving up with the brakes on. At significant cost in fuel economy, etc. For some reason I don't hear of people tuning their PCMs to do this. (Maybe nobody thought of it?) :confused:

Gotcha, and it's probably because the TB gets bad enough fuel econ as it is, and I know that I initially created the post in regards to improving responsiveness or performance. However as you've stated, responsiveness is kind of a foreign term when you're dealing with SUV's. I would like to feel more of my vehicle when I'm actually driving it though, which is why I decided to start redoing the suspension before anything else. I'm still wondering if replacing the mounts with stiffer ones would let me feel a little more engine.

The friend that I've been talking to owns a 2002 Acura RSX, has little to no resemblance to the TB I know. But all he's really done is replaced the suspension with some super stiff stuff and he replaced his engine mounts with stiffer ones. and when you ride in that thing.... the dash literately moves like an inch at idle! I'm not wanting that much rattle, but I would like the feel a little more of the car if you know what I mean. :undecided:
 

The_Roadie

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Nov 19, 2011
9,957
Portland, OR
CDJuda said:
I'm still wondering if replacing the mounts with stiffer ones would let me feel a little more engine.
Stiff mounts, especially misdesigned aftermarket replacements or collapsed OEM ones, are to blame for an annoying 10 Hz rotational vibrations in the I6. And that could set up resonant vibrations in the plastic bits of especially the intake manifold that I saw when my OEM mounts were dead. The risk of breaking stuff from the vibration is enough to make me concerned. I just can't see anybody seeking it out.
 

v7guy

Member
Dec 4, 2011
298
Assuming you have the torque management completely removed, and assuming you don't mind the dash, floorpan, and half the interior buzzing constantly at idle (my motor mounts recently went bad and this is what I experienced, it should be the same for solid/stiff mounts). You still have the motor mounted to the frame and the suspension bolted on with rubber bushings everywhere and the body bolted on with rubber cushions at every point with soft springs and a swaybar that lets the truck wallow over bumps. It's not exactly a combination that caters to responsiveness in any imagination of the word.

If you want responsiveness you need to remove the torque management first, then I would work on bigger swaybars, heavier springs/better shocks, lowering it to get a better center of gravity and some bigger/wider wheels and stickier tires. Think SS, but up a few notches. If that's still not enough start looking at poly or rod ended suspension. Bigger brakes are a really good idea too. You could have a pretty nifty ride at the end of it. But how far do you want to go?

This is coming from a guy with a car with solid motor mounts, rod ends/spherical bearings at every suspension point, huge sway bars, big ole brakes with 14"+ of rotor and 18x11" wheels on all four corners and more than 400hp on spherical bearing coilovers. Until the last few years it was my daily driver and I found it completely acceptable. So when I say I wouldn't go the route of stiffer engine mounts in our vehicles you understand the place I'm stating that from. My car vibrates less with solid motor mounts than the truck does with sloppy motor mounts. The vibration Roadie talks about is significant. You don't want it.
 

CDJuda

Original poster
Member
Dec 28, 2012
221
v7guy said:
Assuming you have the torque management completely removed, and assuming you don't mind the dash, floorpan, and half the interior buzzing constantly at idle (my motor mounts recently went bad and this is what I experienced, it should be the same for solid/stiff mounts). You still have the motor mounted to the frame and the suspension bolted on with rubber bushings everywhere and the body bolted on with rubber cushions at every point with soft springs and a swaybar that lets the truck wallow over bumps. It's not exactly a combination that caters to responsiveness in any imagination of the word.

If you want responsiveness you need to remove the torque management first, then I would work on bigger swaybars, heavier springs/better shocks, lowering it to get a better center of gravity and some bigger/wider wheels and stickier tires. Think SS, but up a few notches. If that's still not enough start looking at poly or rod ended suspension. Bigger brakes are a really good idea too. You could have a pretty nifty ride at the end of it. But how far do you want to go?

This is coming from a guy with a car with solid motor mounts, rod ends/spherical bearings at every suspension point, huge sway bars, big ole brakes with 14"+ of rotor and 18x11" wheels on all four corners and more than 400hp on spherical bearing coilovers. Until the last few years it was my daily driver and I found it completely acceptable. So when I say I wouldn't go the route of stiffer engine mounts in our vehicles you understand the place I'm stating that from. My car vibrates less with solid motor mounts than the truck does with sloppy motor mounts. The vibration Roadie talks about is significant. You don't want it.

Gotcha this is what I just ordered, hopefully this will help. Tony seemed pretty convinced that it would help, I'm dropping the rear 3 inches and the front by 2
TBSSowners.com Store - Belltech Street Perf. Shocks/Springs Combo (Powered by CubeCart)
Before I install it I'll probably grab the better control arms and a bigger sway bar too. Sorry I don't mean to make it sound like I'm trying to hassle you guys, I'm just trying to make it ride like I want if you know what I mean.
 

v7guy

Member
Dec 4, 2011
298
Belltech is a pretty popular brand, so I suspect you'll be pretty happy. I have no personal experience with them though.

The bigger sway bar will help a lot in keeping it level and steady and is one of the first things to do along with good shocks and heavier springs.

Poly bushings are a good intermediate step if you're getting serious, and if you start splitting them you move on to rod ends and spherical bearings.
It's all a trade off.


At the end of the day we're driving a big ole SUV. To be honest, even my car is a big ole heavy pig despite ripping hundreds of lbs out of it. But you can make a decent performer out of something not meant to be a performer. You're up against what us offroad guys are up against, you're just on the other end of the spectrum. No apologies necessary. Just get to work, document it for others and keep improving the weak links!
 

gmcman

Member
Dec 12, 2011
4,658
CDJuda...you don't want stiff mounts on this motor. I have one that is failing or failed and occasionally at a stop in gear I have the dreaded vibration at 600 RPM. It's almost like driving over rumble strips but at half the intensity.....it would drive you nuts if it was like this all the time.
 

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