Would this get me to 400-450 rwhp?

[blackbird1084]

Ok so a few of you have seen where my 355 took a crap, now I'm going to build a fully forged 383. Here's what I'm looking at so far 10.8-11:1 compression, comp 468 (or a custom) cam, 1.7 rockers (.620/.615 lift), afr 180's fully ported, pacesetter lt's, true duals, edelbrock intake ported, and a 58mm tb. Would this get me to 400+? I'm going to end up throwing a 150 shot at it later but I really want it to run 10.9's on motor. Lmk what you guys think.

[Fastbird]

Not with those dinky AFR 180's. I'd go with at least a AFR 210 or better yet the new Trick Flow 21* heads. I'm not going to get all fan boy on AI, but their CNC program is just awesome for our LTx stuff. Their cnc TFS 21* stuff looks to be utterly dominant.

Postin' on the go......

[blackbird1084]

The 210's only flow 20 more cfm at .500 and only 30 more cfm at .500 for the competition ported set. My heads flow 260@.500 right now after they are ported I have no doubt they will flow as much as the 210's. Another reason for not switch heads is the shear cost. Even if I sold mine for $1100 just the standard 210 is $2050 and the comp port is $2550. I can get mine ported for $500 and have every port flowed.

[blackbird1084]

Fastbird why don't you think it would reach those numbers with those heads? If they can flow as much cfm could they not make as much power? And why doesn't AI advertise flow numbers?

[97firehawk]

I say yes its possible.

[AChotrod]

I agree it should meet your goals.

[Fastbird]

Cross sectional volume. A 383 will be held back with those small ports. You might make low 400's but but it could make more with a larger runner, especially in the upper powerband. I didn't mean to poo poo your heads by any means though. They're good, but I feel a little on the small end for a 383.

Postin' on the go......

[blackbird1084]

JRB racing is doing the port work. He's local. He'll check volume, velocity, and cfm on each port to make sure they are within a few cfm of each other. You do make a good point fastbird. Cross sectional volume is a very key component when considering heads or porting them.

[dsmawd350]

i made 415/368 with a 100k mile stock bottom end, stock casted heads ported by nutek/jason short, and a comp cc306. if anyone puts together a stroker and doesnt make 400+ SOMETHINGS WRONG

[blackbird1084]

I'm not even sure what it was making before I never had it dyno'd or tuned. I figure I was making around 360 before so 40hp shouldn't be hard but 90 might be.

[3DFORMULA]

And why doesn't AI advertise flow numbers?

AI shows the flow numbers at the bottom of the page on the stocker 200cc heads page

[blackbird1084]

Now seeing that it makes me even less likely to swap heads. None of those heads flow more than 25 cfm more than my current heads at .500. Do they flow significantly more at .600-.700? Yes but how many of us run .700 lift cams? And the flow numbers under the curve are more important since that's the were the cam spends most of its time.