Are the fastburn heads any good? They're aluminum..

 

Be a Pioneer! Get a set Honestly I have yet to see them in action. I know ONE guy that has them on a 383 in a 91 Z but it's all show and no go...ya know?

I almost got them but I didn't really trust GM's claim of 497 hp on a "typical" stroker motor, etc,etc...I've also see AWESOME flow numbers but they always have a (*) after them stating that the * means they are Prototype flow numbers. How the hell does that help anyone? hahaha Considering magazines "get" 40 extra HP out of them over stock L98 heads must mean they're not terrible and their 210cc intake port should be cool on a larger cube engine.

I went with the competition...Edelbrock's own Vortec pattern E-Tec 200 head No results yet here either!

 

I purchased a GM Fastburn 385 engine 3 years ago and it comes with Fastburn heads. The engine has a 750 mechanical Holley on it and headers with 3:73 gears. In a 3700 lb. Monte Carlo SS it runs consistent 13.0 - 13.15's. I recently upgraded to the Hot Cam kit and now run 12.80's. The heads are good to about 550 hp. The springs that come with the heads are limited to .525 lift. I work for GM and have had some contact with the people who make the heads. I can only vouch for my experiences with these heads but they are just as good if not better then any top name brand on the market today. And the prices are very reasonable for the product you are getting...

 

Sorry to dissapoint, but they flow a lot, lot less than the prototype heads. Actually, they flow less than L31 cast iron vortec heads, which have smaller intake and exhaust valves as well as smaller runners.

A friend of mine who owns a speed shop bought a set when he built his parents motor (its still on the engine stand). He had them flowed and I think they came up in the high 220/low 230 cfm range on intake and did fairly well on exhaust. He had $700 worth of port work done to them by a big time cylinder head guru locally and they now flow in the 27X neighborhood on intake. The advantage of these cylinder heads is that they are a heavy duty casting, not a light casting like a vortec head. However, for the price you can be in the neighborhood of a set of AFR 195's, which would be the route I would go. If you are set on buying a vortec style head, I would buy the cast iron ones. They flow better than the fast burns, and cost roughly $700 less than an assembled set of fast burn heads.

 

My FastBurns were flowed at two different shops (including TEA in Bowling Green, Ky) and flowed slightly better than advertised.

My intake flow #s were in the 237 cfm range at .500 lift and 257 cfm range at .600 lift BEFORE any work was attempted.

They are better now

jms

 

nice denny, i'll deal with you later.................

mine flowed alot better then ported 195's when the two were tested. gm claims your not suppose to touch them??? but considering the money for afr's plus port costs that's alot of money to spend elsewhere.

don't know about gm's claim but they work quite well, just be sure you or who ever puts the motor together knows what they are doing, that's where the real key lies.

 

So how much do the Vortec L31's flow?

 

Why would you port a CNC head?
The flow numbers on the PRODUCTION fast burn cylinder heads, direct from SDPC are as follows:

Intake Exhaust
.100 62 45
.200 129 85
.300 173 120
.400 209 143
.500 230 157
.600 235 166

Here are flow numbers for AFR 195's off their website:
Intake Exhaust

Intake Exhaust Flow difference
.200 132 108 +03/+23
.300 198 156 +25/+36
.400 240 178 +31/+34
.500 260 190 +30/+33
.600 262 194 +27/+28

 

Whats the general consensus on flow and HP....I've heard 2HP per CFM used alot?

I got flow sheets with my Pro-Topline vortecs and they flowed like 225 intake at .5 lift....I thought that was decent considering I got them complete for like 650$. I just didn't have the money for AFRs or anything like that...