Don Terrill’s Speed-Talk

What would be the better choice of cylinder head? street driven 383 11.1 comp SR 255/263 @ 50 600 lift 110 lobe sep, air gap, 750 holley, 1 3/4 primary 4 into 1 3 inch collector. 4spd manual.

The AFR #1068 227 head.

Afr 210. No need for any bigger imo

If you want your power to peak at 7000 I would agree with Joe on the 227 but I think on a street engine looking to stay with peak power at 6500 you would be better off with a 200 to 210 head I have even seen some 383's with AFR 195's making over 500 with a hyd roller in the mid to upper 240 @ .050

With an air gap intake why try to peak higher than 6500? At that point i would go smaller single plane, vic jr or similar

You don't have a torque converter to soften your upshifts, either. I'd surely want to keep the air speed up (shift recovery). My vote is 195 to 210 max.


Shawn

mygtr wrote:What would be the better choice of cylinder head? street driven 383 11.1 comp SR 255/263 @ 50 600 lift 110 lobe sep, air gap, 750 holley, 1 3/4 primary 4 into 1 3 inch collector. 4spd manual.

With either head your biggest restrictor is your intake.

The AFR #1068 227 head actually pours 218 cc's. They run great on 383's. If you're concerned about low end torque, reduce your duration by 10 degrees. And yes, dump the airgap and use the AFR Titan manifold, or a match ported Edelbrock Victor #2925. You should be in the 550hp range.

As you can see from the responses, this is quite a mismatch of parts. What is the weight of the car and will it see any track time? If so, is it drag or road race? Do you have a horsepower goal?

Here's a data point: 240 duration cam, .6" lift, SR, AFR 195 comp ported heads, and Super Vic will give well north of 500HP.

Heres mine. 383 hydr roller 230 deg at .050, afr 195's, same size headers, 11.4's at 118-119 in 3450-3470 lb ride in mid summer temps. Not optimized drag car, summer daily driver. Usually another 2-3 tenths and 1-2 mph easily during winter air. Oh and i shifted 6600-6800. Power held on beyond 6500