higher compression any tuning needed?

[XxRedDevilxX]

I am rebuilding a stock 6 bolt motor that had bad rings and I'm putting it into my talon. I cant really find any pistons worth getting so i was going to put some 9to1 compression forged pistons in with the stock rods. Will any tuning be needed? Will there be any problems with doing this valve clearance issues etc... Also will i need fuel mods any sooner if i add bolt ons? thanks

 

[dsmtalontsi95]

I think you need to be alot closer on your tune, meaning you can't run as lean as a lower compresion.

 

[XxRedDevilxX]

But as far as stock ecu and all stock parts go just throwing in some higher compression pistons i wont need to tune the car differently?

 

[kidrabbit84]

As long as you have the following you should be ok with a stock ECU:

Head and block not shaved beyond factory limit
Healthy fuel system (higher flow pump would be good insurance)
Good head gasket
Do NOT boost above stock (10 psi or so)
Free flowing intercooler
Run good pump gas - 93 only
Cool/Normal running motor (under 210 deg F)
Do not run the car hard in high heat (95+ deg F days)

I broke in my 7 bolt with Weisco 9:1's on the stock ECU, and then racked up another 2K while I collected goodies for a GM MAF-T for my DSMLink. ANY boost above stock or lower grade gas would require a tune.

I had no valve to piston clearnce issues with the Weisco's. I had at least .180" of piston to valve clearnce with a .008 shave and Coremetic head gasket. I have read that .100" is the min you want to go.

Adam

 

[kidrabbit84]

As long as you have the following you should be ok with a stock ECU:

Head and block not shaved beyond factory limit
Healthy fuel system (higher flow pump would be good insurance)
Good head gasket
Do NOT boost above stock (10 psi or so)
Free flowing intercooler
Run good pump gas - 93 only
Cool/Normal running motor (under 210 deg F)
Do not run the car hard in high heat (95+ deg F days)

I broke in my 7 bolt with Weisco 9:1's on the stock ECU, and then racked up another 2K while I collected goodies for a GM MAF-T for my DSMLink. ANY boost above stock or lower grade gas would require a tune.

I had no valve to piston clearnce issues with the Weisco's. I had at least .180" of piston to valve clearnce with a .008 shave and Coremetic head gasket. I have read that .100" is the min you want to go.

Adam

I thought about this some more last night, I would recommend 1 range colder spark plug too.

Adam