Oh believe me I don't expect it to happen anytime soon... but it would be nice if someone could get in touch with all the aftermarket manufacturers and get them to send a set for a comparitive test... only problem is that I think they would all be relativly hesitant, as someone's gonna be at the bottom of the pile, and the test really wouldn't do them much good... but it would be nice.

Someone that has the resources should try to see if they can get it together, someone like W2W would be a good candidate I think, as they have a complete in house setup.

AFR's, ET's, Trickflow, Edlebrock, Allpro, Dart, a couple different sets of GM castings, a set of 5.3's a set of 241's and a set of 243's would be good. I'd say toss in the new L92 heads and the ls7 too, but they need a differnet intake, so it would take away some of the fairness in the testing due to that.


Another good test would to do a comparison of an allout race setup from each aftermarket company, on somethign like say a 408 or 427 with a typical cam and go with a good race style intake, wether it be the edlebrock, harrop or a sheetmetal, whatever. hell toss in a set of the c5r too while you're at it. That would be a nice test too for the guys that are more into the performance end of it and aren't too concerned with streetability or gas mileage, for the guys that are after power more then anything else. Tell everyone the spiton and whatnot so they could mill accordingly, know the cam, etc.etc. Would be nice to see... but will never happen.

 

Yea I think these new raised runner type heads with offset rockers would KICK ***. Why is it taking so long? Never mind.

 

Brian, can you post the ignition advance, bsfc, compression ratio and more complete cam timing (seat,.050, .200, total lift, and if possible .100, .300, LSA and Advance or centerlines), valve weight, and valve spring used? If different pushrods were used could you indicate those.

I would expect the ignition advance and bsfc to give an indication of the thermal efficiency of each head. The compression ratio would give a clearer indication how much difference a couple of CCs here or there may have meant (especially dealing with such small differences.) The cam timing would indicate how the dynamic compression was affected and if it may have been over/under cammed for some combinations. The valve spring, valve mass, and pushrod information would indicate how well the system implemented the cam profile, especially at higher engine speeds.

I would have expected the AFR and TF to have significantly less advance and lower bsfcs. It is also possible, for the displacement and engine speed range, one set of heads may have been over or under cammed.

If this was a 347, my rough calcs indicate that the 2ccs was nearly .3 in compression ratio. And that the compression ratio was a rather low for some of the heart shaped chambers.

Publishing the full set of numbers for all the head, cam, intake comparisons would take away a lot of the mystery. At least for you best LS port, the TF, and the AFR. This could be here or at your website.

I would be interested in seeing your head, the TF, and AFR, all with 11.0:1 static compression and a 224/228 114+2 cam with LSK or XFI lobes, 1.7 rockers, ported FAST intake, 90mm TB, and 921 or equivalent pressure springs. On 91 or 93 octane.

 

OT
Dame,
The dyno numbers were provided by Rick. Just ask him.
Actually with the Comp 1.85's it made 20 rwhp more at 200 rpm less,
but seemed to run better with the stock 1.7 rockers so we went back to those. Also the value train was to heavy with the Comps. in our opinion at that time. The same heads are being used on a daily driver C5 427 F2 pushing 1,200 rwhp. for the last two years.
Back on topic.

Again good information from Brian, Tony and David.

As far more data points, all you have to do is look at the new OEM improvement on the MAF, TB, intake, valvetrain and heads. Obviously, they saw room for improvement and just not limited to the heads.

 

Have some time right now so I figured I would add my input on this thread.
Please read this is your interested in my oponion, which is based off quite a bit of experience.
First off....
Thanks Brian for the test's. I do however agree with JRP in the fact that I would like to see all the results not just the ones provided. If you have more info post it I am sure everyone would like to see it.
Next...
I will say this. The graph's shown is something many of us have known or at least assumed for quite a while including the guys at TEA/TSP/Patroit etc.
You take a set of the Patroit LS6 heads, TSP LS6 stage 1 heads or something like what Brian provided in his tests and add a 90/90 on top and it should beat out a ETP/AFR/etc with a LS6 and stock TB.
The price break down favor's the cheeper head especially if you have a LS6 inatke already.
Stage 1 ported heads assembled with springs, stock valves etc.
1200 dollars tops.
Fast 90mm intake and TB I see GP's for 1150.
Total is 2350. Now you can minus your stock heads, stock TB and stock LS6 intake.
Say 500 for all and you have 1850 out of pocket plus P Rods/Gaskets etc.
AFR's are 2300 minus say 150 for the stock heads so your out 2150 or so, and even more if you want them milled (which everyone does)
HOWEVER with the AFR's/ETP's or whichever aftermarket proven brand you choose there is the potential of more power once more money is saved.
Take the AFR/ETP's and throw the LSX 90 combo on there and you can make some killer power and have the potential to make more power on avarage then a budget head.

More thoughts.....
TEA should have milled the heads even. Why???? Because the LS1 casting start as a 66.67cc's and they milled this set down to 61 or whatever it was. Therefore milling the AFR's would have made the comparision more equal. Why mill one set and not the other?
In summery what I gathered out of this test is that the LS6 intake/stock TB and 10:1 compression can really make a potentially nice setup seem weak.
Make sure when picking your h/c package you set a budget and work off that budget.
Brain has prooven there is a very smart way to go if your on a tight budget and are only doing this once. We all know that there is a great market for all different heads and proof of that is the fact that TEA now offers Trick Flow aftermarket heads that they do the port work on.
I am a HUGE TEA fan and have used them for quite some time. Brian has done probally 50 plus sets of heads for the guys here in Ft. Myers and mostly the mustang groupe. We use them at out shop in almost every fast mustang we have, but I am a believer of being equal so dont list me as a AFR bandwagon bitch because I am clearly not.

Thanks again for the work Brian now post up the rest of those results.

 

JZ's TA, are you able to get the same compression with the same cam with an ported LS6 or 5.3 that you can with a AFR, TF, ET, or Dart?

 

Do not forget to add the EXTRA COST for the larger 1 7/8 KOOKS headers which the TEA Stage 1 heads liked so much.

TEA Stage 1 heads....................... $1000.00
90mm FAST intake and trottle body..$1200.00
1 7/8 KOOKS headers and Y pipe......$1000.00 + roughly
_______________________________________
Total...........................................$3 200.00

 

Yes sir, without a problem.
P/V clearence wont be the same but the larger cam used would still clear without a problem.

 

True but I was only trying to show the differences between the parts that wouldn't be used on both setup.
The AFR's could use the 1 3/4 or 1 7/8 Kooks as well.
I wasn't adding all the parts or it would have been way more. Didn't add gaskets, pushrods, (sometimes injectors) headers, cam, etc. All of which are the same price for either setup.

 

This is where I start to have a problem. The heart or peanut chambers should support more compression and have a lower bsfc. They should simply burn better.

 

And they might, but for those wanting the most power and a higher amount of compression while running a large duration cam need to either flycut of run a different piston.
1 reason the ETP head is so far superior.
It is 62 out of the box and have quite a bit more P/V then a stock non milled head.

 

This is why I went with TEA ........

https://ls1tech.com/forums/dynamometer-results-comparisons/492833-dyno-tea-5-7-stg1.html

 

50 RWPH and 60+ RWTQ gain with no other changes other then changing heads?, if so that's impressive.

 

Yep that was it. Not sure about what the compression is with them. They are your budget $999 head with the stock gaskets that you sent with them.

 

ET and TEA are among the best head porters in the country (Dart and AFR only port their own designs, which are also good).

If flycutting is an issue, the aftermarket heads provide more clearances. However, if you are invested enough in an overall setup to need a big cam, flycutting shouldn't be an issue.

Given the time invested, I don't see the big difference in spending an extra $1200-1400 in a project that may take 40 hours and include clutch/torque converter, gears, differential upgrade, etc. and cost over $6,000 complete.

Now there are lots of classes where the rules won't let you run an aftermarket head...but if they do, and you are dealing with head, headers, cam, intake, tb, etc., you will be moving the compression close to the max, the quench close to the min, and a cam that meets your needs. Patrick G's graphs that are in the 460hp with different power curves with different cams is a better baseline. Seeing the different setups with ET, TF, Dart, TEA ported in addition to the AFR would be a great comparison. Then seeing where the knock sensor kicks in would be a good indication of combustion quality.

 

LOL, I remember that post, I think it got closed in the end by the mods because their were so many inconsistencies in his story and he couldn't provide any dyno sheets.