Failure to hump AFR leg

guru

Well-known member
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Mar 25, 2008
Messages
393
One of the things that piss me off is AFR leghumpers. Nobody can go fast without AFR. I mean its like trying to argue the merits of islam in a mormon temple most places.

(Pardon me, I am drinking the bottle of champagne that came in the mail today)

So anyway, having seen more than a few people get banned from various interweb forums for daring to challenge the AFR religion. Here is some fun:

Dart doesnt muck about with flow numbers anymore. They have evolved past that. But here is their iron 200cc head flow numbers:

.200" 130/109
.300" 194/158
.400" 242/198
.500" 274/208
.600" 283/214

Here is what AFR advertises for their streetheads:
195cc-Std-Head-Flow-Graph2.gif


The dart heads have smaller valves. (2.02 vs 2.05)

There are plenty of good products no need to hump the same leg as everybody else. Not a fan of sloppy seconds, thirds, forths and so on.
 
i agree there are forums where everyone says what heads should i get and people jump right away and say AFR AFR AFR and most all of them have nothing to base there info off of.
 
Don't get me started......I already had this conversation with BB. Gave him links and all....

I don't know wtf is in the water, but there are people who if you insist that if you don't buy AFR you're an idiot.

FWIW, Guru helped me with it a bit, I spent about 6 weeks of my spare time talking to 4 Engineers, who have backgrounds in head design and fluid dynamics, and multiple high profile engine builders an compiled a 6 page paper on what it takes for a head to work. If you guys want to see the results, I'll post it. It's very fact based and accurate. I had each engineer validate the others claims and all read the final draft and blessed it.

Bottom line, dry flow numbers are only one metric of little value when determining the characteristics of a head. Quality of flow is just as important. Dry flow benches vary and are inaccurate. So if we can not use this as a basis for "better" I can stay sane. :wink:

That being said, I will say with complete confidence, AFR makes some pretty big, IMO unsustainable claims. If you buy Brodix, Dart, Canfield, TFS, Edlebrock, AFR, you will have just about the same power. Every one of those products is a quality product.

The delta is sub 30 HP difference depending on the combination. There is no single brand vast superiority. Sometimes one will get more, sometimes the other.

Brodix did a test. They threw their out of box IKs on a motor and then took them off and put their fully CNC ported heads on a motor, and got 30more HP. Same head, one ported one not. So when you compare heads, if one is ported I guess we can assume an immediate 30HP advantage.

Ok, I'm done....
 
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i agree there are forums where everyone says what heads should i get and people jump right away and say AFR AFR AFR and most all of them have nothing to base there info off of.

Catalog jockies trying to achieve peer acceptance by buying cool parts.

If you went to other forums, you would not know that any other head exists other than AFR. One guy on another forum actually said "I have been recommending AFR for years and will never recommend anything else." Is that a recommendation or a leg hump? Is it possible that there are circumstances that AFR may not be the product? Nah. Point is he said for 13 years. Well, a couple years ago they had oil problems and casting issues, yet this guy kept recommending them. It's a sickness, really.

One guy had the birth of his first child and actually posted "LOOK AT MY FLOW NUMBERS"!!! oh, btw, my wife had a baby last night... Sick sick sick.

Here's the issue. On another forum a kid came on and wanted 300HP out of his L98. He said "I'm going to buy AFR heads and XXX Intake".

Does that sound like solid advice to anyone else to get 300HP out of an L98? That's $2500 in parts.

Cam, rockers, and headers. Port the intake. result: 350HP for $1100 exceeded his goals, spent less, and has a better performing motor. But he didn't buy AFR heads. Some idiot on some forum convinced this guy the first mod he had to do was buy AFR heads. THIS I have a problem with. And it seems to only exist for AFR leghumpers. I can't think of another product where people are SO insistent you have to buy it. It's a cult. Really.

Here's how it goes:

Question:
My tire loses air

Response:
Do you have AFR heads

Answer:
Yes

Response:
Let's look and see if the rim is defective

Here's how it goes the other way:

Question:
My tire loses air

Response:
Do you have AFR heads

Answer:
No

Response:
You need AFR heads, that will fix your problem.
 
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OK, now you guys are aware of my insanity.

Dammit Guru, now they're going to come here. You had to start it. If they do come here, and the Bat Signal goes on, it will prove Guru's point, and provide some entertainment.

Wait for it.....wait for it.....wait for it......it's coming......wait for it.
 
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OK, now you guys are aware of my insanity.

Dammit Guru, now they're going to come here. You had to start it. If they do come here, and the Bat Signal goes on, it will prove Guru's point, and provide some entertainment.

Wait for it.....wait for it.....wait for it......it's coming......wait for it.

Technical discussion and valuable information about heads and flow are welcome in this thread but we don't need any debating, bickering, name calling that started over at CF to continue here at VetteMOD.
 
AFR makes a good head, dont get me wrong, they put a lot of development time into and I doubt they would release a crap product, but they arent the sole mechanism to a fast motor.

Personally I picked dart as the heads I am going to buy mainly because of the exhaust port shape and location. I also believe in their development process. Brodix also develops their products similiarily but their exhaust ports are the D shaped ports and makes headers a pain. I wanted square ports.

Many dyno tests have dart and brodix making every bit of power as AFR. Their flow numbers are lower (sometimes) but that could be because of teh bench and fixtures used.

I have yet to see an apples to apples comparison of Dart to AFR with similiar treatments. For instance, the AFR heads are a partially CNCed heads. You can get some Dart Pro 1s with the super mod cnc package for a charge over the base price.

Dart and brodix both make a good product as well and should be considered side by side with the comparable AFR product. I mean its not like you arent about to blow 1500 bucks on heads or so. If you wanted a truck you would be a fool to not consider both the F150 and the Tundra instead of just walking into the GMC dealership.

Sales propoganda is sales propoganda, everybody has it.

Remember flow numbers are the amount of fluid of a homogenous consistancy that flows through the port and valve, a gas with a suspended fluid isnt quite the same thing when you are looking for fluid suspension and distribution.

So if I were to do an apples to apples test, I would like to see comparisons on power on the same bottom end, an appropriate camshaft for each head for desired peak torque, HP, and shift point, carb jetting, timing comparison, and o2 reading.
 
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AFR makes a good head, dont get me wrong, they put a lot of development time into and I doubt they would release a crap product, but they arent the sole mechanism to a fast motor.

They are a fine product. One of the top knotch products on the market. That's the point ONE of the best. There is no superiority gap. Period. It's a Ford/Chevy argument.

The claims annoy me, greatly overestimated and unsubstantiated and I think telling people to spend money on that basis is nothing short of thievery.
 
Technical discussion and valuable information about heads and flow are welcome in this thread but we don't need any debating, bickering, name calling that started over at CF to continue here at VetteMOD.

I agree. I hope people can stick to the technical aspects, or marketing aspects. That's what the discussion is about.
 
I agree they have the best marketing department in the automotive world.
 
I agree they have the best marketing department in the automotive world.

Of which I am jealous. I can only dream of having that kind of marketing. Hat's off!!

They do have a good product to back it up, so it works. Just not a superior one.

I think the only other better marketing is Harley Davidson. When AFR gets people to tattoo themselves with their logo, I'll be impressed.
 
I agree they have the best marketing department in the automotive world.

I went from stockish iron, to Edel, back to iron, and now #113 casting L98 heads on this engine in 11 years.....

never considered AFR, cost and lack of quality in the castings....didn't trust them then, nor now.....Freeking EDEL been around since Henry made a fathead....

:eek::amazed:
 
I agree they have the best marketing department in the automotive world.

I went from stockish iron, to Edel, back to iron, and now #113 casting L98 heads on this engine in 11 years.....

never considered AFR, cost and lack of quality in the castings....didn't trust them then, nor now.....Freeking EDEL been around since Henry made a fathead....

:eek::amazed:

To their defense they did fix the casting and oil issues. (anyone faint?)

Two things need to be looked at in head development.

Wet flow, which is used by ALL the manufacturers, except AFR and Canfield I believe, and a machine called "SPINTRON". The Spintron lets engineers look at parts in the operational environment of 5000, 6000 RPMs. If AFR could have done that with their old castings, they'd found the oil problems.

I know that there are a few head companies using Spintron technology. For us, this is good. Better results, cheaper products, faster time to market. http://www.spintron.com/ These machines are even outfitted with high speed cameras to capture everything, even inside the cyl, to see how they work when running. They can take the high speed images frame by frame and get very specific as to what works and what doesn't. This is the type of development that is the future. Those without this technology will fall behind.

I think with this new technology, we're going to see things change real fast real soon in terms of all points of engine development.
 
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I agree they have the best marketing department in the automotive world.

I went from stockish iron, to Edel, back to iron, and now #113 casting L98 heads on this engine in 11 years.....

never considered AFR, cost and lack of quality in the castings....didn't trust them then, nor now.....Freeking EDEL been around since Henry made a fathead....

:eek::amazed:

Herpes has been around forever too, doesn't mean it's a good thing.
 
I agree they have the best marketing department in the automotive world.

I went from stockish iron, to Edel, back to iron, and now #113 casting L98 heads on this engine in 11 years.....

never considered AFR, cost and lack of quality in the castings....didn't trust them then, nor now.....Freeking EDEL been around since Henry made a fathead....

:eek::amazed:

Herpes has been around forever too, doesn't mean it's a good thing.
:lol: :lol: :lol:
 
I agree they have the best marketing department in the automotive world.

I went from stockish iron, to Edel, back to iron, and now #113 casting L98 heads on this engine in 11 years.....

never considered AFR, cost and lack of quality in the castings....didn't trust them then, nor now.....Freeking EDEL been around since Henry made a fathead....

:eek::amazed:

Herpes has been around forever too, doesn't mean it's a good thing.

Perfect. Give gene some credit, he did upgrade.
 
I agree they have the best marketing department in the automotive world.

I went from stockish iron, to Edel, back to iron, and now #113 casting L98 heads on this engine in 11 years.....

never considered AFR, cost and lack of quality in the castings....didn't trust them then, nor now.....Freeking EDEL been around since Henry made a fathead....

:eek::amazed:

Herpes has been around forever too, doesn't mean it's a good thing.

:kissass: Asshole.....:devil:
 
well... some say it's all the expensive research that justifies the high price for AFR heads, I think the aggressive advertising is a big part of what's bumping the price ... IMO too many people believe that if it's expensive it must be good... just one example: the intake Tornado for $50 :push:

I guess somebody has to buy all these expensive products to support our economy and keep the cash moving....
 
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