OSU Sam

First off let me tell you my background. I have thoroughly read GM LS Series Engines - The Complete Swap Manual by Joseph Potak, How to Rebuild LS Series Engines (S-A design) by Chris Werner, How to Build and Modify GM LS-Series Engines (Motorbooks Workshop) by Joseph Potak, and Performance Fuel Injection Systems by Matt Cramer & Jerry Hoffman. So I feel I have a good base knowledge of LS engines, and Tuning. Also I will have a degree in mechanical engineering by May from Oklahoma State University.

My first question is what is the cheapest way to get a motor tuned and running to perfection? Why I ask this is because I was looking at Megasquirt and assembling one myself and tuning it, but you can't accurately tune the spark tables without a dyno. So what is the point in buying a stand alone computer, or tuning software like hptuners if you will need a dyno anyway? Wouldn't it be cheaper and easier just to keep a stock computer and get it tuned at a shop?

I have an lm7 block and stock heads right now. This is my starting point. I don't have a car to put it in as of yet. But I want to understand what I'm doing before I try to put it in a car so that I don't waste money.

mrvedit

Great questions.
Hopefully people here will give you some opinions and insight.

Here is a recent thread on how to tune the timing tables without a dyno:
https://ls1tech.com/forums/pcm-diagn...-hptuners.html

If you just want a car to drive with max performance, then having a good dyno shop tune it is the only way to go.

But if you get more satisfaction out of learning it yourself, and it seems you do, then either start with a OEM system and either HP Tuners or EFI Live, or something like Megasquirt.

tonypaul

iTrader: (2)

Depending on what features you want, (my opinion) the Microsquirt is the most cost effective if your running a non electronic transmission. Dyno tuning is great for getting a great tune but with you can get a really good tune with just street tuning. You will need some way of logging (like MegalogViewer) so you can make adjustments in your tune.

Along with a wideband and almost any of the popluar tuneing sysytems (and some time) you can get a really good tune without a dyno. Now if your running a boosted motor or alot of nitrous and are looking for a perfect tune a reputable dyno tuner is almost a must.

OSU Sam

I'm glad to hear that is very doable without a dyno. I agree the microsquirt is a really attractive option for $800, and everything it includes. If I choose to run some sort of automatic transmission with the microsquirt is it best to run a stock ECU in parallel, or something else entirely? I've read that keeping a stock ECU is good if you're running an automatic. Thanks for the replies, they are very helpful.

mrvedit

No, the stock PCM/ECU will not work in parallel with another one. (OK, I've heard it of being done, but ridiculously complicated.)
Why not use the MegaShift? That is part ofthe MegaSquirt family.

OSU Sam

I have not heard of the megashift, but that looks like a good way to go. Thanks for the input. So with megashift and megasquirt I would only need sensors. They are relatively cheap other than the wideband. Anything else I should know that I'm missing? (Also I understand that I will have to buy a couple things to make a megasquirt.)

Would it be better to build a MS2 and build a harness instead of going with the microsquirt? I believe I could run a 58x reluctor wheel which would be better. And I think it would be cheaper but much more time consuming. I believe the MS2 has more inputs, so I could run a stepper Idle Air Controller.

I don't completely understand what an ICA controller does. From what I understand it is an computer controlled electric motor that controls the MAP sensors and Temperature sensors? The other option would be a Pulse Width Modulator? (PWM) Which is better and why? I couldn't find a clear answer through google. Sorry for the noob questions.