I'd like to see the under the curve gains, both HP & Trq.

 

Hello again...

I will try and further clarify some of the recent testing we completed, as well as try to answer some of the questions that have been brought up. The topics I will go over are in no particular order....I tried to jot down most of your concerns and I will do my best to address them.


Engine Dyno versus Chassis Dyno....WHY?
The answer to this one is easy....It is far more effective to swap heads, degree cams, change manifolds, etc., on an engine dyno, then trying to do the same testing leaning over a fender and dealing with all the other hassles with an engine installed in a vehicle. The R&D and development time that took four full days on an engine dyno would have been doubled and been a much larger PITA on a chassis dyno. Also, eliminating as many variables as possible when testing (i.e. the driveline) always makes for better accuracy and repeatability. Chassis dyno testing will commence over the next few weeks and we will post our results as soon as they are made available....Unfortunately, the waiting game once again, but we are in the homestretch now.


Just to clarify, all AFR 205's are fully CNC ported, however, the finished volume is still smaller than an unported factory LS6 casting which is 211 cc's.


Does engine dyno gains relate directly to chassis dyno figures?
Yes and no.....Yes, if the parameters of the testing was exactly the same. Seeing how both the "Stock" configuration and the AFR headed configuration both had the same benefit of no accessories or water pump losses (we ran an electric pump), I would expect the gains on the engine dyno to be very close to what you would see on the chassis dyno as well (assuming your current motor is virtually stock and mimics our baseline configuration with your only modification being the Z06 manifold and long tube headers). By the way, the baseline engine did in fact put up 428 HP with the benefits of the longtube headers, better manifold, and no losses thru accessories. I didn't think it would show that strong a result, but the numbers don't lie and once again, it's the reason I initially wanted to discuss net power gains....that was the pertinent information gathered from the testing.


Test procedures.....Both stock baseline and AFR power figures were recorded thru the mufflers with the 1.75' long tube headers as well. With only the addition of the 224/228 camshaft (.581 lift) and the AFR 205 cylinder heads, we generated 515 HP (up 87 HP from our stock baseline…however, if you viewed the curve past peak HP, well over 100 HP was gained above 6500 RPM’s). The better manifold and ported throttle body accounted for the rest of our observed power gains discussed previously.


In regards to the actual engine in question on the dyno, it was in fact the same shortblock Brian Tooley used for testing back in December (with a few hundred more pulls on it since then.....It is an LS1 test mule owned by Westech, one of the shops we use for dyno testing) When tested in the same manner as the TEA heads, we actually saw a touch over 540 HP. This type of test reflected open headers and other parameters unrealistic to a car running on the street, hence our decision to omit this information.

Last but not least, I have included a link to AFR's website where everyone can view two graphs representing our stock baseline runs compared to the best power with the AFR heads, cam, FAST intake, and ported throttle body. Notice how flat the torque curve is and how surprisingly well the motor carries the horsepower right up till 7000 RPM's, even with only a 224 intake lobe and the our “small” 205 runner design. More cam timing would have even looked sweeter if you were just concerned with making the big number upstairs. For a very streetable combination you could use comfortably as a daily driver, we are very pleased with the results this early in the game. We will probably take this exact same combination and bolt a set of our 225’s on it sometime early next month. By the way, we were using a stock computer during all of this testing (not the FAST system), and I feel that some time spent tuning with LS1 edit might have lead to even stronger results.

We look forward to further development of this cylinder head both in house and out (with all the various tuners), so if all of you don’t mind, I need to go “get busy” and finish up with the design of the 225's! Please try and be a bit more patient as we continue the development of a really promising line of cylinder heads.

Thanks from all of us at AFR....

Regards to all,
Tony Mamo

www.airflowresearch.com/ls1_dyno.htm

 

cool deal Tony!

Maybe you can get a print out comparing it to the run made with TEA's head. Now we know they were open headers and had a bigger cam but it would be interesting to have the graghs overlayed so we can see the amount of torque gained from these small hi flow ports.
I am sure Brian wouldn't mind as he is an AFR dealer and it would give us on the forum a little bit of insight to compare it to a combo we are familar with. (ported 5.3 heads and cam)
Heck if you dynoed with open headers use that gragh. Thanks

 

Tony we love our Dynojet numbers in our community but to be sure engine dynos are the best test of power.

So the big question among the shop guys right now is "is there more deck where we need it" that's what I keep hearing. Everyone hopes that your product will have more clamping force and more meat where it counts, maybe you could list out some of the innovations?

 

Trust me on the fact that you guys are going to LOVE the castings....They are much thicker than stock and do in fact have a .750 head deck everywhere except directly under the short turn of the intake port. There is water there so anyone who decides to break out the grinder needs to be aware of that (that was also questioned in someone's post). We only marginally reduced the deck thickness in that small isolated area (It's .625 thick instead of .750), so the overall integrity of the head deck is extremely rigid. Much like a high HP Ford motor, with only 4 bolts surrounding each cylinder, a really thick head deck helps keep everything sealed up. No more "BS" with pushing gaskets etc., under the extreme cylinder pressures blower and nitrous cars are subjected to. We also reinforced the rockerstud bosses and there is much more aluminum around the stud. You could even drill and tap for a much larger stud size and still be in great shape. I'm thinking down the road we might get together with some of the valvetrain experts and offer our cylinder heads with larger than stock threads in the rocker bosses to accomodate stronger aftermarket valve gear. There isn't enough aluminum in a stock head to even think of tapping it larger. Also, You will find there is much more material in the valve spring pockets as well....no more cutting into the roof of the intake port when you open up the spring pockets to accept larger diameter springs. In general, The AFR head is simply a "beefier" casting, but this highlights some of the areas most racers will appreciate the new castings.

In regards to the tests ran by TEA, comparing them to AFR is simply not on our agenda. We were there to develop and gather information pertaining directly to our 205's...if it was never brought up I would have never even have commented on it, however since it was, I felt it was only fair to share some of the finer details. TEA is very dedicated to putting out a great product (among others), and there will be plenty of time for all of the different tuners out there to play the headswapping game with the new AFR's and there favorite brand of ported GM castings (or AFR's for that matter).

I'm thinking 2004 is a pretty good year to own an "LS" small block powered vehicle....can't wait to get wrenching on mine!

Regards,
Tony Mamo

 

The runs with the AFR's & the upgraded cam were made with the "stock" tune in the computer. That means there is alot left on the table in the area of tuning. That just makes it all the more inpressive.

However, I sit back & wait for the 225's. While I do, I order bigger jets.

 

Tony, thanks for the great info.

I'm pretty amazed at the new AFR's and the 5.3 TEA 1.5's

Looks like 2004 will be a good year indeed.

 

Put the G5X3 in there!!!

Can't wait to see the power that can be made once the heads really start being pushed to their limit along with all the other new goodies out there!

 

One other thing to note about the AFR results - this is with a stock CR. There is probably another 15HP or so to be had with 11-1 compression ...

 

Tony, thanks for the reply. The real thing on some folks mind is what will AFR heads do in the hands of some shops. It's not so much comparing current offerings to AFR ported heads, because I think that shops will get even more out of them.

So realistically these heads ship in May and the other ones will ship in June or July? Can you give our community a realistic and not overly optimistic timeframe?

 

I didn't read the entire thread, but I did have to ask. These heads will produce more low-end, mid-range power as well as excellent upper rpm power? I've seen guys with pretty big heads/cam packages and while their peak numbers are impressive, they don't have anything under the curve, and have to be in rpm for the car to do anything. I wonder how these heads would do with everything you listed above, and like a g5x3 cam, or one of TSP's new 'shafts?

 

What gas was used to test this heads?

Tony, are you in Cali?

Impressive and promissing numbers!

 

Tony,when is a reasonable date that the 225cc heads will be available to purchase and is the 225 a different casting then the 205? Also you say that the AFR head has more material between the springseat and intake port roof how can that be without moving intake port lower or closer to piston side of the head?I know that your sbc heads are as good as they get,and I beleive that these new LS1 heads will be just as great,I also think that they are worth waiting for.I also think that AFR is doing the right thing in not releasing this head until you are sure it is ready as bad news travels faster than good.You are helping the delay situation by keeping everone posted on what progress AFR is making toward getting the new heads ready for everyone who,s been waiting for a set.I hope the 225 head won,t be too far behind the 205 heads because that is the ones that I want for my stroker motor that I,m building.Tony keep up the good work and get those heads ready!!!!!!! :

 

same engine dyno,same short block.
How can it get any better than that for those of us considering your heads?
Did they not kill the TEA heads on tq? I wanna see the results!!! Do you want to sell heads right away?
Most of us understand that the decks are going to be a major improvement. But I want to see how much tq is affected with the 20cc difference in intake volume you are talking about!! And so do others.

 

Post the comparison.

Geezus.

 

Different cam specs (duration, lobe seperation, and lift), different compression ratios achieved thru chamber volumes, and different test parameters (not to mention different days with different correction factors)....What exactly are we comparing with all of these variables?? But beyond that, TEA's heads were not at Westech for a comparison against AFR's....I have given you guys plenty of information to start formulating your own opinions about the new cylinder heads...If you need hard data and comparisons beyond that you will just have to wait a bit longer....all of your favorite tuners will have them soon enough.

I hope most of you respect AFR's position on this matter.

Thanks,
Tony M.

 

Hypothetically, lets say the TEA, Patriot, CNC, ET, AFR heads (Did I leave anybody out) showed exactly the same torque and power numbers/curves on the engine dyno. But one company had an intake port that was 20cc smaller. Which head would you chose? Is it really such a hard concept to grasp, that smaller, high velocity ports will cause the engine to accelerate faster? The rules of physics haven't changed gentlemen. Tony's trying to take the high road here and not start a war between AFR and TEA and you guys won't let up. Read between the lines! TEA makes a great product and I'm sure the AFR head will be great as well.

Tony, thanks for keeping us up to date, please don't let some members of our community here keep you from providing us with up to date information. Now quit messing around on message forums, after midnight, and get some AFR LS-1 heads into the hands of the public.

 

the least expensive one.If they made the same amount of tq/hp.What would be the point in choosing the smaller port if power and tq were the same? IF you could save 700.00 on one set why use the most expensive set that makes the same power? The thicker decks are going to help alot with guys making big power. And by big power I mean over 900 hp.

Do you remember back when the AFR heads were gonna be the shiznit for the lt1 guys? Maybe enough people didn't ask enough questions before the product came out. I heard from one source that the 225 were going to make 50 hp more than anyones stage 3 ls6 head from someone at pri show. Now how can someone know this when the product is still vaporware?

Nice that you point out how not to let some members of our community get Tony down..........with your 2 post count's I can see you are real active at the community functions.

 

I am interested in hearing the benefits of high velocity smaller port design producing hp/tq and the value of high velocity for improved performance.

Tony take your time and thank you for the updates. Many of us find them extremely interesting.

Looking foward to how it works with the 224/224 114lsa cam so we can meet emissions testing and get impressive performance out of our ls motors.

 

I guess I just fail to understand why it would be that difficult to A/B these heads against some other S2 head we all know about. AFR is asking for a premium in price, I'd just like to know that it's worth it.

Heck, I'll buy them if it is.


"I hope most of you respect AFR's position on this matter."

Help me out here, I'm honestly NOT trying to be argumentative. If I'm buying a car, I'm going to look at a few things... quality, performance, service, etc...

In a cylinder head, the number of varibles goes down radically, and really boils down in my mind to just a few - the critical one being price vs. power (let's call it area under the curve). Reliability is assumed (if they blow up early, the manufacturer has no business selling them). Quality is assumed.

So, I can look at the good things AFR has done with this head like smaller ports and thicker decks and check both of those in the "plus" column. What I can't do is put a number down to quantify the area under the curve gain relative to a benchmark S2 head, or know what the curves look like, or understand the peak power differences.

If someone wants to charge a premium, which AFR does, I think that's a fair set of questions and AFR should answer them - not an outside tuner or shop.

Pick a standard cam, pick a chamber volume and let them rip, then post the graphs. Doing it independantly would be even better.

I'm willing to wait for it, so just let us know when it will be available and the conditions you're going to run the test under.