Stock LD9 has 200 psi cranking compression with 9.5 compression ratio, intake cam 198 Duration @.050" .354 lift and 187 Duration @.050" .346 lift.
What will be the cranking compression if you dropped in the L.O. LD2 cams? H.O. LGO cams? What compression ratio will be needed to bring up the cranking compression? Whats the highest cranking compression for computer on these motors with super pump fuel?
Around 11.2 is basically max compression ratio for a stock computer with pump fuel
What is your cranking compressions!
my LD9 with straight up LO cams (not 95 intake cam, full .375 LO cams) pulls 205ish.
HO cams .020 off head .030 cometic head gasket stock block deck my does 250s
98grandamld9 wrote:
Around 11.2 is basically max compression ratio for a stock computer with pump fuel
What is your cranking compressions!
Where did you get that information? Because myself along with a hand full of other people have run 2.3 heads with 11.37-1 compression and premium pump gas with no ill effects. Stock computer took it like a pro! I saw little to no knock on a stock tune and that was easily fixed with HPtuners.
.020 off head .030 cometic head gasket how much cr increase is this? I dont have adjustable cam gears to bring the cams back up which I wanna just get custom pistons and use a stock head gasket or maybe the .030. I know it is better to get the quench area down, .02 or .03 is acceptable to where timing isnt a problem. I'm wanting to use the lo or ho cams its a 98 model ld9 with 4t60e tranny. The head im thinking of just doing a port match to manifolds. If i get a port job done how much work needs to be done to ports to get the best velocity and cfm flow rate for the lo and ho cams? who does nice head jobs? So your saying with what cr and ho cams is around 250 psi cranking compression? What cr should you use with lo cams? ho cams?
