blackbird345

Can I just use a metal head gasket? Or how can I lower the compression ratio?

DarkFormula

iTrader: (80)

I'd go with running a thicker head gasket to start. As for the heads, I'd think only machining them could have any major impact on the compression.

DeltaT

iTrader: (5)

If you open your quench (squish) area too much, you'll end up with worse detonation than if you left it alone. You can't go much above .055", maybe .060", and .040" is optimal.

I would call Cartek and see if there is enough material for them to enlarge the chambers at all. That's about your only option for physically changing the CR without touching the bottom end (dished pistons).

Jim

blackbird345

So if i change just the pistons I can lower the ratio to about 9:1? If so any suggestions on the brand?

DeltaT

iTrader: (5)

The JE and JE/SRP pistons are very nice and they have an entire blower/nitrous piston line.

Jim

89Formulaws6

iTrader: (52)

thicker gasket prolly won't lower it enough to help, go with the suggestion above for the pistons

blackbird345

Ok thanks guys

SonnyG

Ok so JE,SRP make pistons specific for FI/power adders...Go with whats proven by the big guys,,,,,Sure you can find some cheapies on ebay...
But the "Big guys" spend millions on r&d.......

And actually you can effectively lower the c/r by about 1 point max with a "huge" mls cometic type gasket....But if you do make sure that you use longer headbolts
torqued in the correct ft/lb and in the correct sequence.......
Run the car check for leaks allow it run till operating temp,,,,
Allow it too cool down and double check if the torque# is correct

And actual water/meth sprayers work excellently......Keep the egts down...
lower detonation etc....Dont screw around and max out the timing for max hp
Thats when you blow snit up.......

Sonny G<