I was led to believe my compression was 11.4.1, After my dyno numbers were way low. I went through my build paperwork to find out builder did

nt use the right numbers on the compression calculator. For the decking he used i think .1. He stated the cc on my milled heads were 56cc. To get 56 cc oit of a 799. It needs to be decks .048. I ran the calculator inserting the .048 and my compression was 10.2.1.

 

Might as well try to boost it the. With that compression ratio lol that sucks he messed up on the calculations man. It sucks not doing everything yourself so things like this don’t slip through the cracks. Maybe a head change at the very least in the future.

 

I’m not the best with dyno graphs but to me the hp stays almost completely flat from 6,000 to 6800. That doesn’t seem right. I could be wrong though

 

I ran the same calculations with some kind of 65cc or so heads and it didnt raise the compression enough. To make it worth it. The power feels good enough and the driveability is great. I took it to the track for the first time. It was like 90* and high humidity. Ran 8.0 in the 1/8 only did 3 passes. Trying to learn what the tranny and tires like.

 

Might as well tip the scales and beat this dead horse of a thread.


C5 Z06
408, L76 block, 4.03 bore, 4" stroke
12cc Dome Wisecos, Gas Ported ported Rings (14.5:1 with an LS9 gasket)
Quench is around 0.046"
TFS 220 heads heavily worked over to be a 245. 2.1/1.6...360ish/270+
Holley Lo Ram with Dual Accufab 4500s on top, 1" plenum spacer
244/266, 640/640 on a 112.5
GZ Vacuum Pump (will run roughly 12 inches at 7k+)
BTR Shaft Mount kit with their rocker arms, 685 ultimate rpm spring kit
Johnson 2126 short travel lifters, Manton 11/32 pushrods
2" Headers, 3" collectors into a single 5" oval spintech pro bullet muffler
E85

 

Why not just starting your own thread??

 

Well the thread was about 408 combos. Seemed relevant to me