I am about to have my 95 (LT1, 383, D1SC with 12#'s, custom 4 inch FMIC) tuned on the stock PCM with pump gas. I know this is not reccommended by some. And I have heard that it may be benefitial to upgrade to a 2 bar map sensor and tuned speed density instead. Does anyone know more on this, and/or what is involved to do it?

Basically looking to get a safe tune on my car without using Meth injection, and not spend the money in a FAST system, or worrying about always putting racing fuel in it. Any other suggestions besides putting racing fuel, or using Methanol injection, without upgrading to the FAST?

 

Give Jeff Creech a call over at Carolina Auto Masters (carolinaautomaster.com). He's tuned many a "big dog" and I believe he can recommend a solution for you.

 

you cant tune very well with speed density as far as Bryan at pcmforless has told me (with the lt1 computer)

 

I second the Jeff Creech at Carolina auto masters idea. He really helped the driveability of my car and picked up about 50 hp over the mail order tune I had. Great guy

 

I am sure Jeff Creech does a good job at tuning. My biggest question here is what exactly is involved with changing to a 2 bar map sensor?

 

With the stock computer it would be a pain in the rear. You would have to remap all the timing tables. Any table in the computer that deals with map would have to be meticulously mapped out for the change in voltage from the 2 bar map. I'm pretty good at tuning and I think this is beyond my capabilities.

I would be interested to see how Jeff Creech tunes his cars. For me the best option I've seen is to go Open Loop all the time with a stock 1 bar map sensor.

 

call alvin at pcmforless.he tuned mine that way with a procharger and 9 pounds of boost it is very streetable and runs 11.6 .This was a mail order tune and i never had one problem with it.

 

my car was speed density to start .I dont know if this matters or not

 

What I did with the 93's was a complete patch. I had probally 3 years in tweaking it and adding new / fixing stuff. I don't know if I would reccomend it honestly unless you where doing some sort of FI that greatly changed boost levels depending on the conditions.. like a turbo car. If you can get by on the MAF you best bet is to.

The 93's HAVE to have a patch like this to have accurate fueling done or else your stuck with a FMU which is kinda touchy.