so some cut fuel.. and some cut ign... ok

im guessing fuel cut is 'safer'?.. but ign cut will help build more boost?

 

Cut fuel makes a lean condition, when i'm on the 2 step a/f's are still in the 11.5 to 12.0 range. This is how I've learned to do it and it seems to be the best results from my experience.

 

You can't go by what the WBO2 says during fuel cut, since it takes an average of the cylinders that are getting fuel and those that are not.

Ignition cut will make more boost, but it's going to be harder on parts. Fuel cut can make plenty of boost on small turbos like the stocker, epecially at higher RPM. For big turbos you'll need some ignition cut to launch on decent boost.

 

Um, you just proved my point of the car going lean as the it is lean in the cylinder it is cutting, thus taking an average accross the 4 cylinders and my readings were 20.0 on the fjo gauge.

 

A cylinder can hardly be considered "lean" when it has recieved no fuel at all.

 

I understand what your saying but ignition cut is not as harmful as you thinkuntil you start to retard timing for the combustion event to happen with the exhaust valves open. That is when EGT's start to skyrocket.

 

ok.. so which one shoots the most flames out the tail pipe?

mine wont build boost on fuel cut, so i guess i'll try ign next.

 

Ignition cut still causes the unburnt fuel that is passed through the motor to be ignited in the turbo/exhaust. The sound created by the two methods is very different. I also don't think that ignition cut is necessarily harmful, but fuel cut will be easier on parts no matter how you slice it. The main problem isn't heat anyway. And it's really only an issue on small shaft turbos anyway, in which case it's unlikely that you need any more than fuel cut, as I have stated now at least twice in this thread.

 

you need to start the retard rev rpm at about 400 rpm before the ignition cut. BE VERY CAREFUL AS EGT's WILL START TO INCREASE RAPIDLY.

Only do this if ignition cut alone can't spool the turbo.

 

What turbo are you using, and what fuel cut RPM?

 

i think its a gt28.. was cutting fuel at 5500.

 

you THINK it's gt28?