ok guys.... builing a 408 and when it comes to the compression ratio calculator i am lost... i always get stuff wrong and then the static and dynamic i am like WTF so if you can help me out it would be great thanks guys

eagle crank
eagle rods
diamond flat tops -2cc valve relive pistons
milled and ported 241 heads to 61cc with 2.02 1.60
and a ms4 cam 239/242, .649"/.609 111 LSA
and a gm head gasket..... so what would my compression be??? any help would be great...

thanks

clayton

 

i think it will be around 12:5 scr or so. your dcr will be very high with that cam,if i did it right i came up with over 9.xx.

 

Enter your info here this should help.

http://falconperformance.sundog.net/compcalculator.asp

Also a silly question but why run 12.5-1 since you have to run race gas? Why not run 14 or 15-1 since you'll have to use race gas anyways and you'll make a good gain in power?

 

I always use this one: http://www.csgnetwork.com/compcalc.html

Enter values as follows:
1
4.03
4
4.065
.052
61
-2
.007

I calculate 12.070993377121803:1

I always have problems calculating DCR, but I don't think that cam can bleed off enough compression to operate on 93oct.

 

thanks guys.... any one know what the dcr will be and should i go with a thicker headgasket or what.... or would i have to run 93 with an octane boster or just race gas.... it does smell good lol