I have a '94 LT1, A4 with the following Bolt Ons:

SLP 2OTL Exhaust, SLP CAI, TB Bypass, 160 degree Thermostat...

I was under the assumption that I really couldn't do much performance wise with PCM tuning except for shift points and making my cooling fans come on sooner. I was at a car show last night and a guy was telling me that I wasn't taking advantage of my 160 degree tstat without reprogramming the PCM....something about the air fuel mixture in a colder running engine...bla bla bla.....

I have a laptop, would it be worth getting the program and cable to do some tuning....or send it somewhere to be done...or don't worry about until I get more mods, like headers, cam and heads.

Thanks in advance for your advice/opinions...

Aaron

 

That guy was full of ****. Granted there may be some minute differences, but I've never heard of anyone shooting for a diffferent AFR depending on coolant temp. With stock or lightly modded cars, you *may* be able to find 10 more hp if tuning with a wideband O2 (the factory tune is typically conservatively rich). Up to you if it's worth the time and money.

 

I tuned a friend's 94' with similar mod's like you and we gained a tenth & 1mph in the 1/4. Also, the car feels much stronger throughout the entire rpm range.

 

dyno charts show that adjusting a/f ratio at wot or (enrichment mode) from 11 to 1 to the nieborhood or 12.8to1 to 13.2to1 can gain you 15 rwhp

 

It probably isn't a bad idea, if you are willing to spend the time and effort to learn how to do everything. I'm in the process now and I know a number of people in my area that wouldn't mind having their cars or trucks tuned either. But it takes a lot of effort to learn just how everything works and what can happen when you change things. You aren't going to just sit down, start changing, and have a perfectly tuned car. Also, you should be prepared by having an extra PCM laying around for when you fry one. Happened to me and I still don't know exactly why (I think my laptop froze right after communication, thanks to my accidently hitting it). But not having a car for 3 days while the new PCM came in was not good. I also plan on doing some more extensive mods down the road (heads, cam, headers, maybe some N2O in the next few months) and then a year or so from now starting on a stroker. Tuning myself will save me a lot of money as well as letting me get the most out of my mods. But, again, I'm spending quite a bit of time learning about it all. So it's up to you. If you have the time and ambition, go for it.

 

Also, I did this without even touching the PE (Power Enrichment tables). Its all about the timing. I think we might be able to squeeze a little bit more out by tweaking the PE tables but its hard to do without a WB O2 sensor.

 

I dunno how old this thread is, but I thought I'd post anyways. I proved on the dyno this weekend that tuning helps with minor bolt-ons. I picked up 12 rwhp from tuning with just my intake and exhuast. =) WOOHOO and the car runs better too.

 

I posted it awhile back, but I got 20 more peak RWHP from tuning, and up to 30RWHP in some parts of the RPM range. The factory tune is WAY to rich, If you fix that and and a couple Degrees of timing you should do fine. If I would have had more time on the dyno I could have gotten more out of the motor. Good Luck- and Tune!!!

 

Yes, tuning on stock motor will yield gains. Bone stock my car turned 14.2 with the stock RSAs. I put on a Moroso CAI, BMR LCAs, Nitto DRs, 160 thermostat along with tuning on the PE tables and timing and turned a best of 13.8. So, get yourself Tunercat or LT1 Edit and tune away!