Low 408 dyno #'s????????
Low 408 dyno #'s???????? I have a 408 with stage 3 72cc patriot heads, stock ls2 90mm intake, and a texas giant cam. We did the math on the compression ratio and it was 10.4 to 1. The car made 450hp/440tq at the wheels, to me that seems low. I think I left alot of power on the table not going with a higher compression ratio. But I think theres alot more power to be had out of this thing. Should I raise the compression ratio with a set of 64cc heads, or is it worth my time. Any suggestions???
Yeah... I might be swaping to a 62-64cc head, and a fast 90 intake pretty soon. I think between the heads and intake I could pull another 30-40 rwhp out of it. Oh....and the exhaust is a magnaflow. How nitrous friendly would 11.5 to 1 be on 93 octane?? I might have to run a stand alone with some 104 in it. How are the new DART heads??? Do they work well with big cube motors??
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Joined: Feb 2002
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From: Loganville, GA
my old FMS 408 dynoed 532/501 (and wasnt even finished tuning..still running 12:1 a/f) with 246/250 630'ish 112+3. thru a M6 w/12bolt w/4.10s. and using my LS2 intake and fast 90mm.
12:1 CR and 93 octane though....
12:1 CR and 93 octane though....
Would be interesting to see your cranking compression? i'm guessing it may only be 120-130psi.
Do you have a graph of dyno runs? Interested where it peaking?
64cc with 11.41DCR sounds like the ticket vs. 72cc and 10.4DCR
Do you have a graph of dyno runs? Interested where it peaking?
64cc with 11.41DCR sounds like the ticket vs. 72cc and 10.4DCR
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If his SCR is only 10.4:1 and using a texas giant cam on 114 (assuming it's 114 stright up) would really be low dynamic compression. He could either switch to a custom cam with a lower ICL and LSA, maybe some advance to increase the DCR or mill the heads to bump up the SCR. I would think you would want to be in the 12.0:1 range with that cam if it's 114 stright up.
yup,dcr is way low for power. how about a set of tfs or afr 225 runner heads with around a 59cc or 60 cc chamber ? your dcr will still be fairly low but should easily run on 93 and probably 91 octane.
