compresion vs cam

[hensleyt]

I have two cams
My new combo is a little different and Im lost
Champion CNC irons and intake
Compression is 8.23 with CP pistons forged crank and rods (.020 in the hole)
1.55 roller rockers
Small 5857 BB turbo S cover
2800 stall stage II EA
I have FT 206-210 and a DLS 210-210
We know there EX timing is different and LS on these two cams differ lob rate different
Both grind great cams but what cam fits my new combo best and why?
I have a easy goal of just 11.5 Et and have done it with both cams
Butt cant really tell and it has not been on a dyno to see torque curve

 

[hensleyt]

My old combo compression was 9.0
Im sure one cam will favor the lower compression better than the other
I think I would like the flatter TQ curve ,but the engine should handle 6500 RPM
This is a track car, that I will drive to and from the track and a Sunday drive (11.5 ET bracket) It is not a DD

 

[Nick Micale]

Tim, I think either cam will more than do the job for you in a 11.50 E.T. class.

You should not be close to 6000 RPM to be competitive as a local friend with a GN won that class for 2 years and he had his original stock cam.

 

[hensleyt]

Im sure I have enough cam and Im over thinking this .
but don't some cam profiles favor the lower compression better than others?
Spool the turbo more torque
Theoretically or mathematical I would chose the one with the flattest torque curve

 

[bison]

It won't matter much at all. Ex close and intake open matter but will be very close on those cams. Both are tiny. More overlap will spool faster with the same lobes but will give up power fast when drive pressure increases. You won't be much over 5200 with that small turbine if looking to get the most out of it. Lower CR and high drive pressure are not what you'd want if looking to run numbers


Sent from my iPhone using Tapatalk

 

[hensleyt]

Im stuck with this CR and I can live with it.MY BAD
I just ran the # on Wallace Dynamic compression ratio calc,
and yes the # are close
FT cam
Static compression ratio of 8.2:1.
Effective stroke is 3.20 inches.
Your dynamic compression ratio is 7.72:1 .
Your dynamic cranking pressure is 151.78 PSI.
Your effective boost compression ratio, reflecting static c.r., cam timing, altitude, and boost of 25 PSI is 20.85 :1.
DLS cam
Static compression ratio of 8.2:1.
Effective stroke is 3.15 inches.
Your dynamic compression ratio is 7.61:1 .
Your dynamic cranking pressure is 148.97 PSI.
Your effective boost compression ratio, reflecting static c.r., cam timing, altitude, and boost of 25 PSI is 20.55 :1.