tempoffroad

I have the dominator efi. I have a turbo and two step wired to momentary toggle on dash. It works fine but not sure what limiter to use. Even with just the spark as the limiter it still pegs wide band lean. I dont know if that ok seeing as its just not really pulling fuel. The soft seems to do the same thing. Looking for advice. Thanks

BMF_Racing

iTrader: (6)

AFR will never look correct on the 2 step because of it firing every other cylinder (giving the WB false readings). I use the Soft setting, but may try the spark only option to see if it helps spool up on the brake.

tempoffroad

Great thanks for replying. I couldn't really tell much of a difference between the hard pulling timing or the soft. They both worked great.

Blown06

iTrader: (32)

I'm procharged, so no need to worry about spool, but I use spark cut on the 2-step.

soundengineer

iTrader: (16)

you pretty much always want to use the Spark cut.....
there are reasons to use Fuel cut, and there are reasons to use "soft"... but for a 2 step you want a spark cut...

dont worry about your wideband readings while on the 2 step...
it will always read incorrectly As its just a controlled misfire.
and while on the 2 step the ECU will always go into open loop, so no worries about it accidentally learning fuel stuff while on the 2 step.

tempoffroad

Thanks guys I love this holley set up!

Blown06

iTrader: (32)

Would like to hear your ideas on reasons for using fuel cut and soft.

compted

I would personally would like to hear reasons for cut fuel and soft limit. New to Holley EFI.

samdogmx

iTrader: (14)

I do spark only on both 2 steps and soft for the main upper RPM limit.

soundengineer

iTrader: (16)

stock ECU's tend to like fuel cut as it leaves the cylinder dry, and its reasonably safe to use
No fuel, No Combustion, No problem...
your plugs can arc-weld inside the cylinder and not have any issues with a fuel cut..
but fuel cut is very very slow typically...and recovers slow as well
it also doesnt create any heat, so it wont help with turbo spooling

Soft cut uses both a Fuel cut and a spark cut
its also pretty slow....
some guys like it for a transbrake 2 step because it has a soft feel and it doesnt come on as violent as a spark cut
but again, due to the use of a fuel cut it doesnt build as much heat to help spool a turbo

spark cut is your fastest responding and most consistent...you can have a pretty close rpm range and it helps with building heat to spool a turbo quicker.
ou will get lots of banging and popping with a spark cut because the fuel will still ignite inside the Hot exhaust....but this is perfectly normal and typically will not hurt anything when used for short periods of time...



ANY rev limiter will hurt parts if you use it for too long
what is too long?? depends on your parts, there is no exact answer.



when we tear down engines to rebuild them... we can tell when somebody has to sit on their 2-step for a long time on the line....bearings get pretty beat up over time...especially the thrust bearing..