Join Date: Dec 1999
Location: Merrillville, IN
Building a Engine for a turbo and need Dynamic/Static Compression Advice
I'm trying to put together a engine and so far have come up with this combo below,, I would like some opinions on what I'm gonna run and maybe some do's and Dont's.
Probe Forged Crank
Probe 11.9cc Dished Pistons
.040 (compressed) Cometic HG
TW 190 Heads 64cc Chambers
Here is what turbo is.
60 series compressor hsg
66mm compressor wheel
68mm turbine wheel
.81 a/r on the turbine hsg
Block is currently still in machine shop so I do not know if the piston is below or above the deck so lets assume zero.
My static Compression will be around 9:1 (calculated)
The Cam Specs are .539" int / .565" exh with a 1.6 rocker. Duration at .050" is 227 int / 236 exh. Advertised duration is 272 / 282. 114 lsa.
I have yet to locate the Intake Centerline numbers but assuming 105-109
Using a Dynamic Cylinder Calculator and assume 1000ft Sea Level and 15PSI I come up with the following:
Static compression ratio of 9:1.
Effective stroke is 2.49 inches.
Your dynamic compression ratio is 6.93:1 .
Your dynamic cranking pressure is 131.75 PSI.
Your dynamic boost compression ratio, reflecting static c.r., cam timing, altitude, and boost of 15 PSI is 14.00 :1.
V/P (Volume to Pressure Index) is 100