3800 spark cut limiter

[darkhorizon]

factory ecu's can not cut spark for rev limiting, and I disabled the fuel cut limiter for obvious reasons...

Anyone know of a "msd" or something with the ability to do some 2step functions on a distributor-less type setup?

[The Dark Side of Will]

Has anyone ever actually blown up an engine using a fuel cut rev limiter?

On a sequential injection engine, hitting a fuel cut means that any cylinder will see a full shot of fuel for one cycle then NOTHING for the next cycle. There is never a lean burn event.

On a batch fire engine, the worst you could do is a cycle with half the fuel in the cylinder that there should be... that's a lean misfire. Again, no lean burn event.


So has anyone *ACTUALLY* had a problem with fuel cut rev limiters?

[befarrer]

Has anyone ever actually blown up an engine using a fuel cut rev limiter?

On a sequential injection engine, hitting a fuel cut means that any cylinder will see a full shot of fuel for one cycle then NOTHING for the next cycle. There is never a lean burn event.

On a batch fire engine, the worst you could do is a cycle with half the fuel in the cylinder that there should be... that's a lean misfire. Again, no lean burn event.


So has anyone *ACTUALLY* had a problem with fuel cut rev limiters?

So would a lean misfire be the pop I can hear from the exhaust of my Quad 4 when I let off the accelerator when moving. It cuts the fuel injectors when the car is moving and the engine RPM is above 1500RPM to help engine braking.

[darkhorizon]

I do believe that I have blown up a motor on fuel cut. It wasnt mine but it was a tune I had done for someone that had the wrong rev limiter setting.

[Blue Shift]

I've always wondered how much the exhaust system likes being turned into a full auto potato cannon with spark cut systems... I've banged my engine into fuel cut more times than I can count without damage - obviously designed that way.

[The Dark Side of Will]

Has anyone ever actually blown up an engine using a fuel cut rev limiter?

On a sequential injection engine, hitting a fuel cut means that any cylinder will see a full shot of fuel for one cycle then NOTHING for the next cycle. There is never a lean burn event.

On a batch fire engine, the worst you could do is a cycle with half the fuel in the cylinder that there should be... that's a lean misfire. Again, no lean burn event.


So has anyone *ACTUALLY* had a problem with fuel cut rev limiters?

So would a lean misfire be the pop I can hear from the exhaust of my Quad 4 when I let off the accelerator when moving. It cuts the fuel injectors when the car is moving and the engine RPM is above 1500RPM to help engine braking.

Probably.
However, lean misfires are hell from an emissions standpoint because they dump raw fuel down the tailpipe. Thus to use both fuel cut rev limiter and have an emissions legal powertrain, OEM's have pretty advanced fuel cut techniques that prevent lean combustion events. Full power one burn, no fuel the next. No lean burn events.

[darkhorizon]

I am sure it works at factory power levels, but when fuel cut comes on via a burnout that brings rpms from 2000 to 6400 in less than a cell on the scanner, you have issues.