[Hacksaw]

Thanks for all the info on my 327. Just thought I would run this by you guys.

Dart Iron Eagle 180cc intake runners 2.02 1.60 valves 49cc combustion chambers. 234/244@.050 with .488/.510 lift. Or 234@.050 with .488 lift across the board. Both with 114 lobe sep. I have forged flat top pistons with 4 valve reliefs. 4.060 bore. Piston specs say 9.18.1 with 64cc heads. Will this raise my compression to much? Also, would there be any clearance issues with valves and pistons? I already have a Holley Contender/Street Dominator intake and Holley 650 HP Street mechanical secondary carb. Keep in mind that this is in a 2800 lb car with 4.56 rear gears and a muncie close ration 4 speed with 26" tall rear tires, so low end power is not much of a factor. It comes up realy fast! Any thoughts please!

Thanks

Shawn

[johnnya]

According to my compression calculator
http://www.bgsoflex.com/cr.html ,
the heads in question would yield a compression ratio of 10.9:1.
Probably too high for pump gas, but IMHO a good compression for the cam.
JA

[454C10]

I would run more cam.

I have a similar setup. 2800 lbs with driver, 3.90 gear, T5 5 speed, 362 sbc zero deck block and pistons, 200 cc dart heads (64cc chambers), 11.2:1cr. I run a compcam 292H with 93 octane fuel without any problems. Pulls hard to 7000 rpm and valve floats at 7200.

I tried a smaller cam (235 at 0.050") and didn't like shifting at lower rpms. After the car hooks up, there is still some rpm to work with when using the bigger cam.

Plus darts flow well on the exhaust size. so use a cam with equal duration on the intake and exhaust. A cam with 244/244 and 110 lsa should work nicely.

If you use a flat tappet cam, please use ZDDP additive in the oil. Cost another 10.00 an oil change.

[techinspector1]

Played around with your motor on DynoSim. Best power achieved by playin' around with cam timing. Arrived at this: 298*/296*, 242*/240*, 0.500"/0.500", Int.C/L 106*, Exh.C/L 111*, LCA 108.5*, 0.006" timing 43-75 / 79-37, 0.050" timing 15-47 / 51-9. This assumes an easy opening and closing ramp, 28 degrees each ramp, 56 degrees duration difference between 0.006" and 0.050" tappet lift. Crane grinds their cams with this 56 degree difference for the most part.

Used these figures for head flow: Got them off Stan Weiss headflow site:
.200 139 114
.300 190 145
.400 218 164
.500 222 172
.600 218 174

10.9:1 static compression ratio, 331 cubic inches, 800 cfm carb on RPM manifold, 1 3/4" headers.

rpm tq hp
2000 285 109
2500 297 142
3000 315 180
3500 360 240
4000 407 310
4500 442 379
5000 464 442
5500 455 477
6000 442 505
6500 419 518
7000 387 516
7500 358 511