Engine run in stand

[JayArr]

Does anyone own/use a test stand? I've looked at a couple online and I'm thinking of buying one this year. I'd really like to be sure that none of the seals are leaking on an engine before I spend hours installing it.

Any suggestions as to make or brand would be appreciated, I'll have a budget of between $1500 and $2000.

One big question is about the engine PCM. I can't imagine I take the PCM from the Envoy and use it on the stand so... is there some sort of universal PCM by Painless or MSD or someone that I can hook a laptop up to and tell it to run the inline 6? It would need to read a handful of sensors and control the fuel injectors and a few other things.

I won't have this problem when I rebuild my Oldsmobile 403 V8, all it requires is a fat red wire from the battery to the distributor but newer engines present more complicated problems.

 

[m.mcmillen]

I think that if was inclined to get an engine run in stand, I would get the welder out and make one myself to save money. As far as a PCM, I think the easiest way would go hunt around at a salvage yard and see if you can get a harness from there and use the PCM from you Envoy since you probably have it out anyway.

 

[Mooseman]

Like he said however, the PCM would need to be re-programmed to disable VATS since it will be looking for the BCM. You'll basically need a whole engine harness, sensors, gas pedal and a lot of customizing. AFAIK, nobody makes a universal harness for this engine.

 

[mrrsm]

You might send @limequat a PM ...and see if he has any RMH (Ready-Made Harnesses) in stock designed stictly for Purpose Built I-6 PCM Controlled Engine Break-In Stands. This is an interesting On-Topic Article that covers (3) Ways to side-step the High Priced, Store Bought Versions that includes a Materials-Parts and Tools List that would STILL require either a Full or Partial Harness to handle the Unique Atlas Vortec 4200 LL8 Engines:

https://www.hotrod.com/articles/hppp-1103-diy-engine-break-in-stand/

 

[JayArr]

Thanks for the replys guys. I could always weld it up myself, and I might resort to that if I find I've got time to spare. I'm no professional welder but I built my own rotisserie and different carts and such. The welding part doesn't bother me but there is so much time cutting the metal up into parts and then drilling it and welding nuts on everywhere you want it to be adjustable. The rotisserie took me over a month of nights and weekends. The last cart I built for my AC machine and gear took almost 6 hours and it was just angle iron with a few shevles and wheels. It's no easy task building stuff like this.

I read the Hot Rod article before but I don't like the design too much and I never figured out how to read the next parts of the article. The professional carts look more adjustable and I own big V8s, the inline 6, a Nissan 2.4litre and a GM Vortec V6 so I'm really looking for versatility in what I can mount to it.

Same problem with the computer. Ideally I'd like one computer to run the V6, the LL8 and/or the Nissan, I can make my own wiring harnesses. The other advantage is that I only need the engines to run, I'm just breaking them in and I don't need to map them all out or "tune" them, just run them for a while. Open loop is just fine as long as it will run and rev up and down. The computer stays with the stand so the engines gets it's proper PCM when it gets put back in the car.

Pics are of my 1990 270SX on the rotisserie, the grey areas are where I worked and then primed with zinc spray.

 

[limequat]

Interesting idea JayArr. I had briefly considered this as well, but quickly dismissed it after considering the work involved. For reference, I charge $699 for a complete stand-alone harness and PCM. It wouldn't make a huge amount of difference if it was on a stand or in a hotrod. Whether you're counting dollars or hours of your time, it would be hard to justify unless you have several swaps planned with the same engine type, IMHO.

 

[JayArr]

I started googleing last night and ended up looking into Megasquirt. (I bought on of the originals in 2001 but never used it). It seems to be a full service unit now and I like that it comes in a kit that I can assemble to save some $$. It also looks like it can be adapted and added onto to run a lot of different engines so it may be perfect for an engine stand. Has anyone ever run an LL8 on a Megasquirt?

 

[limequat]

^ Yes there are a few that have done MS successfully. There is a facebook group for 4200 swaps. The users there could give you more information. Also Marc at emtechmotorsports runs MS on his 600 hp 4200.

 

[cornchip]

Has anyone ever run an LL8 on a Megasquirt?

Microsquirt ECM controlled 1963 Studebaker Lark posted yesterday.

LINK