wish i had more time to work on car myself but my scedule doesnt allow. think i will hold up on carb swap.thats why im a member of this forum it would seem this is a bad idea.i know a real good tuner who makes custom chips very knowlegeable about feuel injection.he is widely known for finding hp and getting cars running like few others.its a bit of a drive im going to get his opinion thanks guys ,may have kept me from making big mistake

 

Good news!

RACE ON!!!

 

I think you have a plan that is much better then what was suggested to you and commend you for making a good decision.

 

Don,

Don't be afraid of FI. It is really not that hard to understand at the level you need to in order to carry on an intelligent and informed conversation. This will also prevent you from being taken for a ride by anyone who doesn't know FI. I personally would never suggest swapping to a carb on a street driven C4. I would never suggest it to one of my customers either. It sounds to me like whoever did the miniram made some errors. If you get your hands on a factory service manual or spend some time doing a search, I am sure you can find the three wire colors you need to that would go to the MAP and their general location. From there start poking around and look for the wires. It's been a while since I have worked on a speed density L98, but one of the three wire colors for the MAP should be specific for the MAP only. Meaning it should be connected to the MAP and nothing else, that should make life a little bit easier when hunting for it than saying something like "It's the third pink wire after this arbitrary branch off".

Good luck

 

thanks for advice ,i havent spent this much time working on a car since i restoed a 68 firebird,i really got frustrated with it and just wanted it running right no matter what it took. really dont have the time to work on it myself and after a couple of months of trying it on my own i really just wanted to get it on the road. do my own work on my zr1,and my c5,i can do most repairs no problem, but this what should be simple l98 had me stumped.i dont think it would be this hard if it werent modified .going to call monday and put a hold on the carbeurater deal until another shop takes a look

 

It comes down to this: For any given situation, there is an ideal air/fuel (A/F) mix that an engine needs for best performance. It doesn't matter what device achieved the proper mix for that situation - truth is where you find it, and a carb might well provide that ideal A/F mix in a given set of circumstances as well as FI. The question is, which system will provide the optimum A/F ratio (and therefore the best performance in any situation) overall?

The computer on your Vette monitors a plethora of variables, e.g., coolant temp, incoming air temp, mass air pressure, knock, throttle position, exhaust oxygen content, spark advance, and actually learns your driving habits and modifies the A/F according to both long term and short term demands and conditions, etc. - It then compiles this info to provide the best instantaneous fuel/air mix, according to learned demands and a 'look-up' table for the conditions it sees at that exact moment. Bottom line: A properly working EFI system will provide the optimum A/F mix over a much wider range of circumstances that the "dumb" carb does.

Your first clue is your mechanic...There IS a wire in the harness somewhere. It might have broken or been cut off, but it is there and can be spliced, if necessary; to sh*t-can the EFI for a nasty ol carb for lack of finding a wire...is high-time cause for finding a mechanic that knows something about EFI!

There are many references on the subject of Corvette fuel injection, but one of the easier introductions - very well written - is "Corvette Fuel Injection & Electronic Engine Management" by Charles Ol Probst (ISBN 0-8376-0861-9). This book will take away most of the fog regarding EFI and give the reader a perspective by which he/she can assess what some "mechanic" might be telling them. After reading this book, I doubt very much you will be inclined to dump the EFI for a carb. But, then again, I can understand why some might prefer the carb to EFI...

One indispensable tool for anyone interested in keeping their Corvette (or any other EFI equipped engine) running well is either a scanner or a laptop with the appropriate software/cable installed. I bought an AutoXray scanner after my mechanic wrote, "No problem found" on his bill. Fifteen minutes after I hooked my (then new) scanner to the computer, I had my answer - an intermittent sensor failure. Since then the scanner has paid for itself many times over by instantly diagnosing subsequent problems (like a dirty connector, additional sensors going bad) on my Vette and some other cars as well. If it were me, I'd have that scanner hooked up in a heartbeat and we'd "go for a ride". But, in any case, I would look for a mechanic that wasn't afraid of technology and knew his way around a computer.

Just my 2¢


P.