Ok so there is all this talk about heads and how they flow better on the low end and all that crap. Well now after looking at AFRs site im REALLY confused. I dont understand this news

http://www.airflowresearch.com%5C/

This makes no sence to me, how can he make 619 hp at only 6500 RPM and a whopping 529 torque at only 5000 RPM. He used what? Basic rules were street style carbureted 366CI engines, no solid roller cams, stock valve angle heads, no shaft mount rockers, chassis style headers, and average HP between 2500 to 6500 RPM to decide the winner.
How the hell do you make that kind of power with only 6500 rpms, and 366 cid sbc??? And whats even more strange is the torque numbers....

Now please correct me if im wrong i know that those heads are BAD *** and i want them. But look what it says on AFRs site. 350 to 434 cid engines in drag cars, sprint cars, and late model oval trackers operating from 4500 rpm on up. Does it not say 4500 rpm on up? So how does he get this amazing 5000 rpm 529 torque?? I dont understand how a head that is supose to not even come alive until 4500 rpms, can make that much power at only 500 more? It makes sence in one way because its only a 215 CC head and can run on a wild 366 im sure. But it makes no sence, why would they say 4500 rpm on up, if the damn heads make **** loads of torque at 5000. That means they they probably had good torque from like 3500 on or better yet even 2500 on. Maybe not torque like the 180 CC heads but still. Can someone please clairify??? Im sorry for being a newb but it just doesnt add up to me. We all talk about making 500 RWHP in a LT1 396 and stuff or a 383. This dude just make 600+ with basically a street setup and no solid roller, and it probably moves at 2500 just fine in a car. even 600 in an lt1 with an auto is probably like 540 to the rear. Last i checked thats 40 more then most people have not even acomplished. Anyways, any ideas????

 

Even a t56 uses more than the 10% you are figuring.

Also figure EVERYTHING you see on their site is marketting and therefor should be taken with a grain or more of salt.
I can't get your link to work but also consider a engine built for an engine only competition may not actually work well in a real car. That relatively low peak torque RPM looks good but there is surely more to the story here.

OK got to the page there is no real info, this thing coukld have required a 1500rpm idle minimum for all we know

 

That wont bother me for 600 hp at 6500 rpms and that much torque at 5000. Anyone else have any clues? 1500 idle, hell i would go for that! lol.

 

I doubt them heads' are out the box afr's.. Those stipulation's are there to make it kinda even playing field as far as exotic part's.. But the heads are the best flowing afr sbc head out there, and they've been rubbed on quite a bit.. Lot more $$$ in them then the 3k dollar asking price..

 

http://airflowresearch.com/articles/article94/A-P1.jpg

http://popularhotrodding.com/enginem...208PHRSherman/

Is this what you are talking about?

You make it buy putting the package together to work extremely well together.

First off Joe ported the intake ports himself, and they were smaller than what AFR puts in those heads. AFR Raised Runner heads are very, very good heads for making power.

Everything on that motor was done right, lightweight rotating assembly, the right cam, compression, intake and header combo, plus all the details.

FWIW I built a motor for that contest as well. On our dyno it made 570hp and 535 ft lbs of TQ. This was with a extremely small 214/224 cam, compared to Joe's 234/234 cam. I used Brodix T1 CNC ported heads from Weld Tech and a Super Vic intake.

Building motors, especially street motors to make 1.46 ft lbs per cube is challenging. It is possible to do so though.

Bret

 

Thats really amazing, well i guess AFR was wrong about the 4500 rpm on up thing, sounds like those heads are capable of pulling from 3000 at leaste.

 

Bret's comments brought to my attention another detail. When doing sometyhing like this an engine builder can do things right rather than having to try to please an irrational customer who believes they "need" the biggest heads and cam for a what will only be a 12 second daily driver.

For competition though a lot of games are played I know some drag racing classes dictate stock lift so the valvetrins are VERY carefully planned out so the lobe actually throws the lifter and catches it on the closing ramp. Just an example of how competition can use ideas and methods totally inappropriate for a street vehicle.

Not saying they are right for everyone but look at Bret's post again and the power he made with a cam so small MOST of you reading this would consider it a waste of effort.

 

No it's more about the right mix of parts.