There seems to be more and more people running the new GM Fast Burn head but not much in the way of feedback.

If money were no object (yeah, right!) and you had to choose between a GM Fast Burn or an AFR 195 (one of the best), which would be your choice? No additional porting allowed, just use them right out of the box.

------------------
Click here to see see my car and hear 5-speeds. http://www.geocities.com/casanoc

In the November 2000 issue of Poplular Hot Rodding, there is a flow bench comparison test between several sets of heads including the AFR 190 and the GM Fast Burns. In addition to posting the flow data for these heads, they set up a swirl meter which can presumably tell things about the quality of airflow into the combustion chamber itself and how complete the combustion process will be. Although after learning how the flow benches actually work, it seems that there could be a HUGE difference in how the head flows while on an engine itself. ANYWAY, results from the test were the AFR's outflowed the Fast Burns at every lift. The intake/exhaust ratio was 73.4% for the Fast Burn's and 82.1% for the AFR's. Both exhibited a great amount of swirl with the AFR's again on top.
Other things to notice: The AFR's have a 74cc combustion chamber and the Fast Burns have a 62cc combustion chamber. So,a dyno test between the two would not be completely fair even if pistons were changed to give a comparable compression ratio. Also, the Fastburn's only come with valvesprings rated to .500 lift. If you plan on using a higher lift cam, then they're out.
CarlC, I bet ya thought I didn't pay attention......You said AFR 195's and I was saying 190's. The 190's and 195's are pretty similar in flow, but as I understand, AFR designed the 195's for single plane intakes and the 190's for high rise dual planes. With this company's reputation and engineering designs, I bet the intake probably DOES matter for maximum airflow results and the head you would buy would be for a specific use.
Bottom line.....If the flow bench is indeed a reliable comparison between Numerical data and actual Torque and HP results, then AFR's are my choice. I've seen very good results on the street and track using AFR's, but as CarlC said, nobody I know has run the Fast Burns. I'd like to see some of you folks that run the Fast Burns to post some stuff here. Particularly other engine components and 1/4 ET's and MPH. I'm a number freak.

That's very interesting. 0.500" lift is not enough. Even in the GM Performance Parts catalog they state that when using the Fast Burn heads with a 0.540" lift roller cam in a 383 you can get 500 hp. Did they swap springs and do spring pocket work?

The AFR's are also available in a 68cc combustion chamber.

------------------
Click here to see see my car and hear 5-speeds. http://www.geocities.com/casanoc

the zz430 engine had the fast burns on it and the gm hot cam it has a 525 lift

I've spewed about the AFR 195's to Carl, so this is more for everyone elses benefit. I've got the AFR195's on my 406. The only difference from the 190's is the extra port size at the intake side. Purpose- as you guys pointed out it's for the big single plane intakes. I got the AFR FloPower RPM intake and had to do a small amount of grinding on the intake manifold to get that perfect, seamless match. Interestingly enough, the same would be necessary for a Victor Jr intake. I have a Victor Jr that I pulled from my engine before I swapped to the AFR heads. My Victor intake has already been enlarged, and the ports are still barely big enough to match the intake ports of the AFR heads. I decided to go with the dual plane route for a change of pace.


No Dyno numbers, (yet) but my butt tells me they breath pretty freely. It shoots up to 6500 RPM on my 406 before the rev limiter can catch it! I run 10.9:1 compression, and the heat dissipation is incredible. I can open the hood after driving it hard for a half hour and it's surprisingly cool.

Get'em Carl, your tesosterone glands will thank you... http://www.camaros.net/forum/biggrin.gif

------------------
Shawn Peterson
1969 Z28, 406SB
http://www.geocities.com/corsican69

hey shauwn do you want to sale the vic jr?
what have you open the ports to, ?
thanks cerbz

Thanks for the correction fellas.......Sorry for the mistake, I apparently had a few spark plug wires off in the old thinker. The .500 max lift springs were for the Vortech heads, not the Fast Burns as I misquoted earlier. I suppose I've read TOO many articles lately and filed some of the info in the wrong catagories. Again, I apologize for giving inaccurate information and thank you for setting me and everyone else straight. http://www.camaros.net/forum/eek.gif

Cerbz,

I'm keeping it for now. One of these days I'll get ambitious and do some manifold swapping just to see which I like better. Besides, the Victor Jr was ported by AFR, so the runners are flawless. I couldn't sell it for near what it's worth.

------------------
Shawn Peterson
1969 Z28, 406SB
http://www.geocities.com/corsican69

Come on Carl, you know you want the AFRs. And let's not whimp out with those little bitty 195 castings. Go for the 210s. AFR is located just 12 easy miles down the road. Make me proud!

Torqer,

Shawn wouldn't let me try his before he installed them, so how about I try yours? Better yet, let me try the whole enchillada! You wouldn't want to put all that effort into intalling the motor just to have to tune it. Let me do that for you. I'm such a giving person! http://www.camaros.net/forum/wink.gif

------------------
Click here to see see my car and hear 5-speeds. http://www.geocities.com/casanoc

Ha Ha Ha...
Carl, you can look but you can't touch. http://www.camaros.net/forum/biggrin.gif