jack kramer

Anybody out there know how to modify the ECU to eliminate the rear rotor redline fuel cut on an '86-'88 NA?

I've seen ads where you can get this done for $100, but I'd like to give it a try myself and save some $ if someone can point me in the right direction.

Scott 89t2

are you talking about boost fuel cut on a turbo motor?? you can solve that for $100. there is no fuel cut on an N/A. there is a rev limiter but it shouldn' come on for 1000rpm past reline. and there is no way you should be going that high on your engine.

jack kramer

No, I'm not talking about a TII fuel cut. I mean the fuel fuel cut to the rear rotor on an '86 - '88 NA that kicks in somewhere between 7600 - 7800 rpm

My car's an SCCA ITS race car and it makes great power high in the RPM band and the fuel cut hits right at the wrong places on some of the tracks I run. I know other ITS racers that have had this modification done that run their cars up to 8500 rpm and beyond. My engine is not properly balanced to run at or above 8500 rpm, but 8000 - 8300 is a reasonable range. Those extra few hundred RPMs would make a big difference!

Scott 89t2

ok, so you are well past redline, thats the rev limiter. the only way I know around it is go get an ecu chip such as www.mdrace.com it'll move the redline as well as give you more power. I think there are around $300. but you'd have to check your class rules before getting one.

the other poeple I guess either have this, or 89-91 engines which cut out at high 8's.

is the rev limit fuel cut?? I would think it would be ign. cut, much better.

then again I know someone with an 86 race car and he revs to low 8's with I'm sure the stock computer, so maybe there is another way. but I don't know what it is.

jack kramer

I know about the mdrace ECU. It's illegal in my class as it alters the stock fuel maps. However, you can modify a stock ECU to remove the fuel cut - that's what I'm trying to learn how to do. BTW - it is a fuel cut, not an ignition cut. It cuts the electrical signal to both rear rotor injectors.

Some guys get around this by splicing the wiring harness so you are running both the front & rear rotor injectors from the ECU signal for the front rotors. I'd rather not hack my wiring harness. I've got a couple of extra ECU's so I'd rather go that routecause it's no big deal if I mess one up...