Japery

I have a 77 corvette with a HSR and a 355 crate engine and i only run this car in the northern summer. Im wondering can I turn off the closed loop so I can simplify the tune process? If so how?

Kevova

Wrong forum should be c3 or engine mods, but what are you using for efi?

Japery

Iv started this thread here because I dont think there is alot of c3s with TPI, thats c4 stuff. Im using the 91 AUJP 1227730 ecm. Iv got the Moates hardware and Tunerpro RT software. Bought all that stuff but forgot that i cant understand any of it. Iv been slowly learning but still have major issues with the tune.

Kevova

What are your mods? Is there any tuners in your area?

Japery

I live in Rochester NY and no one wants to touch a "Frankenstein". I have 10 to 1 compression,better heads and bigger cam so stock chip is pretty rough. Running Very rich

Kevova

If you are able to make data logs, you could contact pcmofnc, TPIS , or someone else with details of what you have. They will work with you to make a chip. L98 ecm uses replaceable prom for tune. Car cruises canbe a good way to find help finding a tuner.

aklim

Fewer and fewer people want to touch a C4. When you go to a large shop, they send you to the "expert" or "specialist". That is the guy who drew short straw to work on old junk. At least, in the places where I interviewed the guy on what makes him special for the job.

You need to find out what you have around you. Call Dynojet and see if they know of tuners and let your fingers do the walking

Hot Rod Roy

To answer your question, you don't want to turn off your "closed loop". That's the best part of an EFI system! Once you've got it tuned, the closed loop system will compensate for all the variables the engine will experience. That's what makes it so much better than a carburetor!

Japery

sold the EFI system and converted to a carb. Had the car siting for 3 years screwing around with the tuning and gave up. Hate to say gave up but, it is what it is.