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after a bit of feedback from ecu tuners out there on best mixtures for response/turbo spool while still being reasonably safe, as the engine goes from vaccum to boost.

car is a r32 rb30/26head with .82 rear gt35, cruising vaccum is around 8 in/hg, and comes on boost fairly quick once you put throttle down, so what do people suggest for mixtures as it builds boost??

example:-

5 in/hg= 14.0 AFR

0 vaccum=13.5AFR

2psi =13.0AFR

4psi= 12.5AFR

8 psi= 12.0AFr

12psi=11.5AFR

has any body played around with mixtures in this area to gain response without loosing safety of the tune?

Cheers

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Really depends on your method.. on my previous ride, I used somewhat a lean spool technique where timing was a tad relaxed, but coming onto boost it was quite lean

Some tuners prefer to richen it up a bit and dial in a tad more timing.. really depends what makes power with the least knock. I'm no professional but I do whatever works for me.

Lower timing causes the mixture to burn a tad later, so the heat is not absorbed by the motor and ends up out the exhaust manifold creating more exhaust gases to spool up the turbo.

But in saying that, lower timing will also make the car produce less power, where as higher timing and more fuel will produce the power but the "burn" has more time and the engine absorbs all the heat enery producing a lower EGT.

All in theory, but whatever works right? EVO boys all go lower timing, but lean spool their cars

I'm no expert but,

5 in/hg = Go lean until you loose more power than fuel. On a good setup the engine will make the same power at 16:1 and 14:1

0 vacuum= Still stick in the 14's for economy. Even high 14's are fine. With 6 throttles you can get to 0 inHg at 2/3 throttle. Your egt's will be high if sustained for a long time at full throttle...... but its only ever there for a nano second.

2psi = I would still be 14's on your engine. Same deal, not going to maintain this for extended periods at full throttle.

4psi= 13.5AFR

8 psi= 13.0AFr

12psi=11.5AFR

14+ psi = As rich as you can run it without hurting power too much. The richer you run it the safer it will be. That's why nissan do it.

Forget about ramping boost unless your going to run anti lag. Component heat is what you want, not lean mixtures.

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