Well...kind of right. Up to .400" The stock Vortec heads flow better but after that the bigger Fastburn head pulls ahead by a lot. On a small cube, small cammed motor, the Vortecs would kick *** but really we're comparing a 170cc port to a 210cc port, small valves vs. big valves, etc. A bigger motor would appreciate the Fastburns. I almost bought a set but there are NO reliable flow numbers anywhere on the net. Last I seen GM themselves had flow numbers but they said they were from a "Prototype Fastburn Head"...They also claim 497hp from a "typical" 10:1 383 with off the shelf parts, etc. I can't trust that but I do look forward to seeing good numbers.

 

I have seen flow #'s, and they were 40 cfm less than the prototype heads from GM.

A friend of mine put them on a motor he built for his parents. I think they flowed 232 before porting and 278 after porting on the intake at .600 lift @ 28hg. They were about 40 cfm below the prototype head numbers if i am not mistaking.

On the plus side, they are not a light casting like the vortec heads and feature a bigger intake runner like you stated.

 

Your just biased.

 

Not really, the canted valve heads just make some sick numbers.


As for the Fastburns.......

http://www.popularhotrodding.com/eng...0207phrbeckem/

This guy ended up with a small bore motor with a pocket ported Fastburn head on top of it. 556hp is not bad from that small of a bore.

Bret

 

Where does it mention fast burn heads?

 

That story doesn't tell about the Fastburns, but the teardown story showed that he finally ended up with the Fastburns.

Bret

 

I figured that everyone was running some kind of canted valve head. I know that the Yates head is canted, what about the P7s?

 

The Yates one should be canted, but NASCAR makes them go use a non canted design. I guess they gave them a canted valve head for 2004.

The SB2.2 and P7's are very similar and are canted valves.

The GM and Brodix Canted Valve heads are just a little more extreme.

http://www.brodix.com/onlinecatalog/...page33-34.html

The SB2.2 is a 11* x 4* intake and a 8* exhaust where the canted valve stuff is 14* x 4*(int) & 10* x2*(exh)

Basically that means you can get a bigger valve in there. 2.200-2.250 CV vs a 2.180" in the SB2.2. More valve means more flow.

That's my reasoning for it.

Bret

 

I Like Pie.

Alex

 

Whoa, calm down son.

 

Hey Alex, if you have any personal issues, want to belittle someone, or just talk trash to them be my guest but please take it up in email or private message... just off the forum.

If you care to productively add to the discussion at hand in this thread go right ahead.

Thanks.

 

Alex,

Other than I know it's a little excerpt from your post that was deleted because you can't operate in a civil society.

I post on things I have an opinion on, and things I don't I don't post about. Period.

Getting on to the Yates head. It was derived from the Cleveland head, which is a canted valve head.

The fact that it has a "full eleven degree valve angle" is not the reason why it's not canted. The SB2.2 head is an 11 deg valve angle with a 4 deg cant.

The valve angles on the Yates were changed (to 7.5* and 8.0* degrees with no side cant) to reduce piston valve relief depths and permit higher ring packaging and the combustion chamber shape was revised for very high compression levels.

You might want to read this before you go on making a post about Yates heads.

http://realbig.com/detomaso/1999-01/844.html

Bret

 

Someone told me once that SOME of the fastest N/A SBF use chevy heads (aftermarket or factory im not sure). Is that true?

 

No it's the other way around like the canted valve chevy heads.

 

But where are they on the racetrack or on the dyno? Neither of these designs are new, but they haven't shown much other than innovative designs. I'm having trouble finding good dyno data and track numbers for engines equipped with Coates heads. A couple of good links would be appreciated.

No offense intended, UB.

My $.02