GMHTP LS2 Head Shootout - Now in easy-to-compare graph form courtesy of PianoProdigy
01-18-2007, 07:50 AM
#41
TECH Addict
Join Date: Jul 2002
Location: Somewhere I Belong
Posts: 2,906
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Tony Mamo @ AFR
Hello....
Decided to quickly chime in here and thinking it would be helpful if I copied and pasted my former response from the original thread (concerning the test results) because I know most people won't bother to take the time to read it. Also, I have been dyno'ing and testing our product for a few years now and have never seen an actual dyno curve like the one represented in this test with a "blip up" in the middle like that. Why that was the case I certainly don't have a clue but it's the only curve in the test that looks like something was amiss. All of you have seen independent tests and results that also aren't representative of that curve, but none the less thats the way it goes.
I think I bring a few other points to the table in my initial response that also have some relevance here....
--------------------------------------------------------------
Guys...
Don't forget the AFR's had the distinct disadvantage of having the lowest CR of the bunch....it's all about cylinder pressure and more of it would have fattened the TQ and power curve at every RPM point, not to mention improved the BSFC #'s some of you made mention of earlier (this might have been one of the pulls with more fuel which made similar power to the pulls with less directly effecting those figures as well).
Also, I mentioned earlier in this thread that an engine dyno is not the best tool to show the benefits of smaller high speed port designs, lighter rotating components, etc., etc., but both of which legitamately help a road race car come off a corner harder (showing they are genuinely beneficial to power/TQ output). Neither of these scenario's will show you their stuff on an engine dyno unless you test the engine at a more representative sweep in acceleration (much faster than the typical 300 RPM per second). An inertia style chassis dyno is a different story....much like your car it will accelerate at the rate the engine at WOT will allow it to....its not a fixed rate of acceleration determined by an engine dyno's water brake. To a point it's the same argument with big carbs, what works the best on an engine dyno wont necessarily perform the best in your actual vehicle.
A small runner head that will make the same or better numbers than a larger runner head will always be more "alive" and have more snap in the throttle driving around town, not to mention be more fuel efficient doing so. It simply makes for a better dual purpose vehicle which most of you guys reading this are probably running. Are these perks as well as the one most overlooked IMO which is their ability to consistantly deliver the goods worth the extra coin....to some yes, to other's maybe, but I have been on this board now for approaching three years and there are very few, if any, un-satisfied AFR customers. Hard to argue that....
As I also said earlier, you guys simply have more good choices to make pertaining to cylinder heads, and while this testing could have been done slightly differently (trying to equalize CR, perhaps on an inertia dyno, etc., etc.), it was clearly alot of work and very time consuming and also shows that the differences between the better heads on the market has certainly narrowed quite a bit. Considering that, other just as important factors (besides sheer peak power figures) need to be pondered....there is a cylinder head out there for everyone....the tough decision is figuring out which heads are best for YOU.
Good luck with that....LOL
Feel free to call or PM me in the event you are considering our product and have some questions....
Regards,
Tony M.
--------------------------------------------------------------
Decided to quickly chime in here and thinking it would be helpful if I copied and pasted my former response from the original thread (concerning the test results) because I know most people won't bother to take the time to read it. Also, I have been dyno'ing and testing our product for a few years now and have never seen an actual dyno curve like the one represented in this test with a "blip up" in the middle like that. Why that was the case I certainly don't have a clue but it's the only curve in the test that looks like something was amiss. All of you have seen independent tests and results that also aren't representative of that curve, but none the less thats the way it goes.
I think I bring a few other points to the table in my initial response that also have some relevance here....
--------------------------------------------------------------
Guys...
Don't forget the AFR's had the distinct disadvantage of having the lowest CR of the bunch....it's all about cylinder pressure and more of it would have fattened the TQ and power curve at every RPM point, not to mention improved the BSFC #'s some of you made mention of earlier (this might have been one of the pulls with more fuel which made similar power to the pulls with less directly effecting those figures as well).
Also, I mentioned earlier in this thread that an engine dyno is not the best tool to show the benefits of smaller high speed port designs, lighter rotating components, etc., etc., but both of which legitamately help a road race car come off a corner harder (showing they are genuinely beneficial to power/TQ output). Neither of these scenario's will show you their stuff on an engine dyno unless you test the engine at a more representative sweep in acceleration (much faster than the typical 300 RPM per second). An inertia style chassis dyno is a different story....much like your car it will accelerate at the rate the engine at WOT will allow it to....its not a fixed rate of acceleration determined by an engine dyno's water brake. To a point it's the same argument with big carbs, what works the best on an engine dyno wont necessarily perform the best in your actual vehicle.
A small runner head that will make the same or better numbers than a larger runner head will always be more "alive" and have more snap in the throttle driving around town, not to mention be more fuel efficient doing so. It simply makes for a better dual purpose vehicle which most of you guys reading this are probably running. Are these perks as well as the one most overlooked IMO which is their ability to consistantly deliver the goods worth the extra coin....to some yes, to other's maybe, but I have been on this board now for approaching three years and there are very few, if any, un-satisfied AFR customers. Hard to argue that....
As I also said earlier, you guys simply have more good choices to make pertaining to cylinder heads, and while this testing could have been done slightly differently (trying to equalize CR, perhaps on an inertia dyno, etc., etc.), it was clearly alot of work and very time consuming and also shows that the differences between the better heads on the market has certainly narrowed quite a bit. Considering that, other just as important factors (besides sheer peak power figures) need to be pondered....there is a cylinder head out there for everyone....the tough decision is figuring out which heads are best for YOU.
Good luck with that....LOL
Feel free to call or PM me in the event you are considering our product and have some questions....
Regards,
Tony M.
--------------------------------------------------------------
Originally Posted by bad95killer
Nice job Alan & AFR proven Heads though and Tony M clarified the extra low end torque point > https://ls1tech.com/forums/showpost....5&postcount=71
peace
peace
01-18-2007, 08:30 AM
#42
12 Second Club
Join Date: Oct 2004
Location: troy, mi
Posts: 70
Likes: 0
Received 0 Likes
on
0 Posts
Maybe these comparisons should be done at a neutral site. Each set of heads should be ordered and delivered as they would to a customer(builder not knowing that they will be "tested")
It seems that Patriot was not invited to the bash- why not?
It seems that Patriot was not invited to the bash- why not?
01-18-2007, 09:30 AM
#43
Originally Posted by Ksett
East Coast Supercharging hand finishes all their TFS heads and claim 4-5 rwhp with the hand finishing. They wouldn't bother if they weren't getting that on the dyno.
01-18-2007, 07:54 PM
#44
TECH Apprentice
Join Date: Sep 2005
Posts: 339
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Xtnct00WS6
Where exactly though do they port? I wouldn't be surprised if they smooth out the exhaust to rid it of cnc marks. Do they do any work to the intake port?
02-11-2007, 03:44 PM
#45
Originally Posted by briannutter
READ that article very carefully. Some heads were handworked more than others when they arrived. That MAY or MAY NOT be the way you'll get them.
Bret
