Connordtf

hey i drive a 1993 c4 corvette with cam, 1:6:1 rockers, and magnaflow exhaust. Im sure theres more done to it because when i bought it i was informed that it was not stock. At the moment the car runs super rich and cant find anyone that can tune it. Any recommend plug and play tuners?

vader86

No plug & play stuff. Where are you located? You need to find a shop that can tune that on a dyno.

Really need to know what the cam specs are to try a mail-order tune.

aklim

Even Plug and PRAY tuners can't do much if you don't know what has been done to it. Can you check with the PO, aka previous crook and/or moron who did all this stuff?

Connordtf

located in central fl, i have contacted many shops and theyve all said they dont provide dyno tuning for my car and they usually direct me to hp tuners or diablo sport which only supports 99 and up. Also the car was bought with the cam so im not sure of the specs. I think im going to go with a custom tune from Fastchips

confab

If it is new to you.. I might make sure it is running right first..

Example: It's rich? A bad injector will cause you 100x the trouble if you dump a mail order tune on top of it.

Connerdsny

Hey Connor, its Conner...

If you want to learn to do it yourself Moates has all the equipment and know-how. Being able to datalog will help you immensely with diagnosing early gm fuel injection

aklim

Put your location in your profile and hold on. Someone might come along with a name of a person who will tune old stuff. I'd call dynojet and see if they know people in your area and call around.

And what will you tell them? Tune it for an unknown combination? Kinda like you saying "Sell me a suit for a man." and hope they can guess what fits.

vader86

Ed Wright can do good tunes mail order, but if you dont know the cam specs, its going to be a bear to tune it right even for him.

You need to find out what camshaft the previous owner put in it.

856SPEED

Are you sure there is an aftermarket cam in it? 1.6 rockers add lift and duration to some extent......cam is a bigger project....ask the PO for the cam card he put in it......every after market cam comes with one for this reason! Hard to believe someone would go through the aggravation of a cam install and 1.6 rockers and not have it tuned....

If that is the case, you have a big guessing game......Life's lesson.....don't buy a pig wrapped in a pretty blanket....!

Unwrap before writing the check!

modified.....that rings the red flag bell w/o documentation.

aklim

I would do that before money changes hands. What usually happens is the buyer gets "Corvette Fever" and pushes away all doubts and buys it and glosses over the details till it has to be done.

I believe it. Too cheap, too stupid PO and an over enthusiastic buyer and this is what happens.

Unless you can get it stupid cheap like at scrap iron prices, I wouldn't

No glove, no love.

I'd want everything to be working and verified by an independent mechanic.

Kevova

Make sure there are no vacuum leaks. You could check PROM in ECM 1 to see if it has been tuned and 2 if it has ,maybe who did it. There is adapter to install tuner chips. It's easy to do most of the mods. Tuning is the tough and sometimes more expensive part. Trying to figure out cam without removing front cover will not be easy. Using a dial indicator you could measure lift on intake and exhaust. It might give a clue what cam.

aklim

How did you do it? I know there are whispers about being able to tell if the ECM has been altered for warranty purposes but is there a way to identify that "Kilroy was here" where you can identify the writer?

Tuning is a skill that is hard earned. I either pay for the guy's developed expertise or spend more time on the dyno learning the nuances if I can find enough use for it.

Kevova

These are replaceable chips possibly company or person who made it signed their work. If I were making them commercially; I would have some way to ID it was mine. I would have a record of who and what I made it for. It also takes an adapter since the tune chip does not replace the "cal pak" in the mem cal. The earlier ecm didn't use an "all in chip" mem cal, the cal pak was a smaller separate chip.

I am not a computer science person. Back around Y2K GM started hiring computer forensic people" to analyze PCMs related to powertrain failures. It started with diesels and other boosted engines then moved towards everything else. The aftermarket advertised increased performance using thier tuning products. GM found the aftermarket was able to overwrite the oem programming. Manufacturers don't want to pay for powertrain failures because some changed redlines or boost levels. When GMC did the Syclone and Typhoons, a " tamper strip " or sticker was placed on mem cal door. Strip was to inspected as part of powertrain repair. If it was damaged the warranty was effected. GMC knew someone would try to make "Hot Chips" which would jeopardize the 4.3 turbo program. GMC wanted to ensure the warranty wasn't paying for it. The requirement for sealed PCM of OBD2 was attempt to deter altering of powertrain calibrations for emissions. Tunerxxx advertises burn away temporary programs, manufacturers buy and install it. Then work on how to detect it. It's similar to the game, computer hackers and security analysists play.

To check cam is basically degreeing cam. Only difference you measure and document lift and duration. Then calculate what you have. PITA in general, but could be necessary in a competition situation. Where creativity with the rules could make minimal disassembly a requirement.