AFR Independent Flow numbers inside
HumppinSS, those are Absolute Speed heads, not patriots. Flow and HP gain are good across midrange also.
I am not knocking the AFR's, the more new products out there the merrier for us. Edelbrock has a head offering in the works for us soon. This can only be good for the sport.
I think the AFR's will rule with FI because of the thick deck, however I don't think the porters a going to be able to do anything earth shattering with the AFR's that they can't already do with other castings.
Also the slow release of these heads with promise after promise month after month has become a little anti-climactic.
I am not knocking the AFR's, the more new products out there the merrier for us. Edelbrock has a head offering in the works for us soon. This can only be good for the sport.
I think the AFR's will rule with FI because of the thick deck, however I don't think the porters a going to be able to do anything earth shattering with the AFR's that they can't already do with other castings.
Also the slow release of these heads with promise after promise month after month has become a little anti-climactic.
AFR is a pretty good product. The only bad things I have heard is about the cooling passages, and the fact they get a lil pissed when you call them and up and ask for the heads w/o seats or guides 
Originally Posted by bigdsz
HumppinSS, those are Absolute Speed heads, not patriots. Flow and HP gain are good across midrange also.
I am not knocking the AFR's, the more new products out there the merrier for us. Edelbrock has a head offering in the works for us soon. This can only be good for the sport.
I think the AFR's will rule with FI because of the thick deck, however I don't think the porters a going to be able to do anything earth shattering with the AFR's that they can't already do with other castings.
Also the slow release of these heads with promise after promise month after month has become a little anti-climactic.
I am not knocking the AFR's, the more new products out there the merrier for us. Edelbrock has a head offering in the works for us soon. This can only be good for the sport.
I think the AFR's will rule with FI because of the thick deck, however I don't think the porters a going to be able to do anything earth shattering with the AFR's that they can't already do with other castings.
Also the slow release of these heads with promise after promise month after month has become a little anti-climactic.
Its a new product be happy they didnt release **** just to have it rushed to the market...
I am all for waiting because I beleive these heads will perform. They have allready released a 205 cc runner that flows 300 cfm. Most aftermarket runners are well beyond 205 cc and the integrity of the head has been compromised. Along with less P to V clearance and a shallower deck. my money is on the 205's for the street and i am pretty sure with a runner size of 225 cc it will be COMPARABLE if not EXCEED what we have on the market today....
TECH Apprentice
Joined: Aug 2002
Posts: 365
Likes: 0
From: Indiana
We will see. A local guy is getting them and I'll run him. I really doubt he will see gains that are worth $1000. I almost did jump on this bandwagon but couldn't see spending the extra cash. I guess only time will tell. We have the same setup except heads. If they perform so much greater, I will buy a set but if its only a tenth or so faster then my car is now, screw that. I can think of much better things to spend my cash on.
flow numbers don't tell the whole story.you can have a head that flows 280cfm and make more power than a head that flows 300cfm.the enviroment inside an engine is a lot different than a flow bench.there are a lot of dynamics that will affect flow that you can't duplicate on a flow bench.reversion is one thing that comes to mind,especially with a cam that has a lot of overlap.that's why on a nextel cup car they will use different port designs for different tracks,depending on where they need their powerband to be.from what i've seen on the board here the AFRs are a great head,with good mid-lift flow and small ports.that's what you want in a street strip car.
TECH Fanatic
Joined: Jan 2002
Posts: 1,205
Likes: 0
From: harrisburg, pa
Originally Posted by jrp
guys, you can spout off you "higher" flow numbers over the AFR's but your not looking at the whole picture. Ryan is the pefect example, his PP 5.3's heads get there *** kicked by mikey's (rapid motors) 5.7 stg 2 heads with stock compression in under the curve power. same cam, mods, and tuning.
Last edited by SAM98WS6; Sep 18, 2004 at 09:08 AM.
On The Tree
Joined: Jan 2004
Posts: 192
Likes: 0
Originally Posted by SAM98WS6
Thats exactly why I have Rapids Stage 2 LS1 heads. For that amount of money I would have chosen Rapid LS6 heads. Good luck with the AFRs..I hope they work as advertised.
Otherwise, I would have gone that route as well.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
You absolutely cannot say that a particular head will perform better simply based on flow numbers. Flow is a very small part of the equation. Port volume, velocity, swirl, tumble and turbulence are all part of the deal. When we developed our port, it was done to maximize the area under the curve and not for flow. A world famous super stock engine builder did our port design and he stressed turbulence as the number 1 killer of power. He said that not too many head folks know what to "listen" for. He showed me two different ports on the flow bench (ours and a competitors) where one port actually produced more peak flow but was "noisy". I could not tell the difference in noise between the two but sure enough when they were both tested, ours produced more power all over with the same cam and header package.
Bottom line is that you cannot judge a head based on flow alone. AFR is known as a reputable company and I would not hesitate to look at them.
Mikey
Bottom line is that you cannot judge a head based on flow alone. AFR is known as a reputable company and I would not hesitate to look at them.
Mikey
TECH Addict
Joined: Dec 2001
Posts: 2,298
Likes: 2
From: new england
Originally Posted by mikey
You absolutely cannot say that a particular head will perform better simply based on flow numbers. Flow is a very small part of the equation. Port volume, velocity, swirl, tumble and turbulence are all part of the deal. When we developed our port, it was done to maximize the area under the curve and not for flow. A world famous super stock engine builder did our port design and he stressed turbulence as the number 1 killer of power. He said that not too many head folks know what to "listen" for. He showed me two different ports on the flow bench (ours and a competitors) where one port actually produced more peak flow but was "noisy". I could not tell the difference in noise between the two but sure enough when they were both tested, ours produced more power all over with the same cam and header package.
Bottom line is that you cannot judge a head based on flow alone. AFR is known as a reputable company and I would not hesitate to look at them.
Mikey
Bottom line is that you cannot judge a head based on flow alone. AFR is known as a reputable company and I would not hesitate to look at them.
Mikey
What's That Sound? I was talking to the guy at WeldTech about minimum cross section and velocity and one thing he mentioned was that high-velocity cylinder heads are quieter when flowed on a flowbench than cylinder heads with less velocity. Has anyone else noticed this?
TECH Apprentice
Joined: Aug 2002
Posts: 365
Likes: 0
From: Indiana
Originally Posted by PREDATOR-Z
It doesn't matter whether you're beaten by an inch or a mile, the fact remains YOU ARE BEATEN. 
Last edited by Justin99TA; Sep 19, 2004 at 04:11 AM.
Originally Posted by Justin99TA
The local guy is getting the 225s so we will see. When I was looking into heads before I was told by speed inc that you did not want 225s for stock cubes and that is what he has? Please explain
the AFR 225's should they pan out to be everything as advertised should be badass; stock cubes or not. most ls1 ported castings end up being 230+cc so maybe you misunderstood what speed inc told you.
TECH Senior Member
Joined: Mar 2004
Posts: 14,620
Likes: 17
From: BFE
Originally Posted by justin99TA
When I was looking into heads before I was told by speed inc that you did not want 225s for stock cubes and that is what he has? Please explain
Originally Posted by Tony Mamo@AFR
The biggest thing that bothers me is all of you guys are missing the boat on the entire CONCEPT the 205's are based on. It was designed to be a great all around STREET head with the potential to improve fuel economy, reduce emissions, enhance throttle response and drivability, and still provide GREAT ALL AROUND POWER. Based on results we have compiled, I would be the first to admit that a 205 would probably show a 10-30 HP advantage over most "Stage II" ported castings, while still providing the other benefits noted above (in addition to the beefier casting quality). Documented in part of our emissions testing was the fact that the AFR equipped car produced 20+ additional RWHP, less emissions gases, and an increase in fuel efficiency of 1.5 MPG. This was over a bonestock Z06 with no other modifications whatsoever. Needless to say, we passed with flying colors...
As some others have pointed out....Is a swap to AFR 205's a "cost effective" move if you already have a good set of ported factory castings? NOOOOOO!!!
If you don't care about cost effectiveness will it help improve OVERALL PERFORMANCE....YEEEEES....In most cases I BELIEVE that to be true.
I have more to say but will save it for another day....the last thought I will leave you with is the engineering department is currently working on digitizing the new AFR 225.....In my opinion, the 225 will be the ultimate head for guys looking to make BIG power in a stock displacement shortblock (and of course you stroker guys as well) and put an even larger gap on most of the competition, our own 205's included. The 225 head will make a swap from ported fatcory castings a much more cost effective mod.
Now AFR will be on a level playing field as most ported factory castings are 230 cc's or greater
As some others have pointed out....Is a swap to AFR 205's a "cost effective" move if you already have a good set of ported factory castings? NOOOOOO!!!
If you don't care about cost effectiveness will it help improve OVERALL PERFORMANCE....YEEEEES....In most cases I BELIEVE that to be true.
I have more to say but will save it for another day....the last thought I will leave you with is the engineering department is currently working on digitizing the new AFR 225.....In my opinion, the 225 will be the ultimate head for guys looking to make BIG power in a stock displacement shortblock (and of course you stroker guys as well) and put an even larger gap on most of the competition, our own 205's included. The 225 head will make a swap from ported fatcory castings a much more cost effective mod.
Now AFR will be on a level playing field as most ported factory castings are 230 cc's or greater
TECH Fanatic
Joined: Jan 2002
Posts: 1,205
Likes: 0
From: harrisburg, pa
I would like someone to help me believe this: (AFR quote above)
"I would be the first to admit that a 205 would probably show a 10-30 HP advantage over most "Stage II" ported castings"
then the horse will be dead....
I just think the gap is getting narrower for improvement..aftermarket heads over old time chevy..big gap for improvement...aftermarket head over LT1...smaller gap...aftermarket head over LS1....small gap.... I cant be a blind follower...
"I would be the first to admit that a 205 would probably show a 10-30 HP advantage over most "Stage II" ported castings"
then the horse will be dead....
I just think the gap is getting narrower for improvement..aftermarket heads over old time chevy..big gap for improvement...aftermarket head over LT1...smaller gap...aftermarket head over LS1....small gap.... I cant be a blind follower...
TECH Apprentice
Joined: Aug 2002
Posts: 365
Likes: 0
From: Indiana
Originally Posted by PREDATOR-Z
Please read the below carefully. This is from the mouth of the tiger himself. No second hand, hear say.
Now is this clearer to you??
Now is this clearer to you??
buying heads. If they are that great I will buy a set but if not I dont' see the point
TECH Fanatic
Joined: Jan 2002
Posts: 1,205
Likes: 0
From: harrisburg, pa
Originally Posted by Justin99TA
This is totaly different from what I was told lst January when I was looking into
buying heads. If they are that great I will buy a set but if not I dont' see the point
buying heads. If they are that great I will buy a set but if not I dont' see the point
remember the first post in this thread showed "averagish" independant flow numbers...we are all just giving our opinions...
show me....
Last edited by SAM98WS6; Sep 19, 2004 at 12:49 PM.