LT4 conversion - Computer

[coloradoformula]

Hey all,

My friend is going to do the LT4 conversion to his LT1. When it comes to the computer would it be wise to get it reprogrammed or to use an LT4 computer off of a firehawk/special edition SS? I was thinking the LT4 computer from the LT4 car so that if he ever takes it to a shop they won't re-set the computer to the LT1. Any advice?


Thanks,
Shaun

[fastTa]

There are differences in the programming between the LT1 and LT4 factory pcm, and there is also the less sensitive LT4 knock module. The LT4 pcm has slightly more aggressive fuel tables and timing curves among a few other things due to the increased performance of the LT4. First of all get an LT4 knock module ($35) and pop it in place of the LT1 knock module :

http://www.projecttransam.com/projects1.asp

If he is doing a true LT4 conversion this will involve alot of time and money (LT4 heads, LT4 hotcam, LT4 intake, 1.6 rockers, higher compression pistons, larger injectors, etc.) there will be some reprogramming neccesary if this is done but it will be less time consuming and cheaper to keep the LT1 pcm rather than obtaining an actual LT4 pcm.

http://www.malcams.com/legacy/misc/LT4.htm

[Craig 94 TA GT]

I would suggest Ed Wright or pcmforless.com. They will customize the computer for you, probably much better than stock LT4 programming. (In pcmforless.com, he will need to buy the adapter to hook up to his laptop. From then, pcmforless will email him the program, he can load it into the computer, then he's set). I believe with Ed Wright, you have to send your entire computer to him ?

[N20LT4Bird]

I sent mine (the whole computer) to ed wright. He did a nice job.