GMHTP LS2 Head Shootout!!
11-01-2006, 06:31 PM
#24
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There will never be a "level playing field" for this type of comparison. Guys will always argue for the head that they already bought. The fact that the TFS heads are 215 and the AFR's are 205 means ****! These heads are comparably priced and therefore compete w/each other. If one company offers a little more bang for the buck, so be it. Some of you are starting to sound like ricers bitching
about this ****!
about this ****!
11-01-2006, 06:56 PM
#26
Originally Posted by N4cer
Um, dude, I'm saying that they compared box stock AFR's to hand finished TFS heads. That's not level. They should've compared either box stock against box stock, or hand finished against hand finished.
Brain - Why were those heads used for the test and not a normal out of the box set like the others submitted? If it is to be a "true" comparison, then why not make it just that? Not trying to start an argument, but very curious on this.
11-01-2006, 07:44 PM
#28
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O.K. I have the article in front of me right now and there are no pictures big enough to show the diff between "out of box" and "hand finished". Maybe all TFS heads come finished that way "out of box". I would not trust the opinion of a GMHTP editor to know this. In fact, a few years ago they build project magnum TPI w/ strope speed. They talked about how great strope was and the project went perfectly. I mentioned strope on this board once and all I got was negative
responses. I would believe the people on the board before GMHTP, besides have they ever had a bad build?
That being said, if the TFS heads come hand finished for 2399 and the AFR heads are 2479 "out of box" , why bother arguing about it. Hand finishing the AFR heads would price them out of the comparison.
If this was a set of "ringer" TFS heads then that is bullshit and you are right. I am just not fully convinced yet.
responses. I would believe the people on the board before GMHTP, besides have they ever had a bad build?
That being said, if the TFS heads come hand finished for 2399 and the AFR heads are 2479 "out of box" , why bother arguing about it. Hand finishing the AFR heads would price them out of the comparison.
If this was a set of "ringer" TFS heads then that is bullshit and you are right. I am just not fully convinced yet.
11-01-2006, 08:17 PM
#29
Originally Posted by Nate_Taufer
My favorite quote from that article:
However, next time around we’ll be looking at the killer new L92 heads and L76 intake that GM Performance Parts has coming out for the LS family of engines. Stay tuned LS lovers, we’ve got a lot of cool stuff coming your way.
Nate
However, next time around we’ll be looking at the killer new L92 heads and L76 intake that GM Performance Parts has coming out for the LS family of engines. Stay tuned LS lovers, we’ve got a lot of cool stuff coming your way.
Nate
11-01-2006, 08:33 PM
#30
Originally Posted by Black02SS
I'll agree with this statement 100%. Maybe someday, someone can do a honest comparison. I'm not saying that TFS isn't a good head, but it is hard to say how well they are when a piece that is tested obviously isn't a production piece.
Brain - Why were those heads used for the test and not a normal out of the box set like the others submitted? If it is to be a "true" comparison, then why not make it just that? Not trying to start an argument, but very curious on this.
Brain - Why were those heads used for the test and not a normal out of the box set like the others submitted? If it is to be a "true" comparison, then why not make it just that? Not trying to start an argument, but very curious on this.
Already have a 460rwhp AFR 205 headed car here.No problem switching the heads and make sure the compression is exactly the same.I would love to see the difference 
11-01-2006, 11:52 PM
#32
Better to look at them as averages.....
For using a stock casting the Livernoise guys did a good job... the Darts aren't bad for cast cast ports that get grosely outflowed by the rest of the heads in the group, I know first hand those heads with some TLC to the guides and a good blending of the valve job can work wonders, I'm sure there is 5ft lbs average in just doing that to the heads.
The interesting part is the BSFC numbers, the AFR is a fuel pig even with less compression it eats gas but does make power with less compression. The GM head is still dam efficient along with the Edelbrock design, and of course the TFS lower valve angle stuff. The Dart numbers are most likely bad here because of the transition from the VJ to the chamber, if that is fixed I'm sure they would pick up.
I agree with them that the Darts in ported form and L92 stuff in would be good to see, the L92's in ported form with a quality VJ would be killer.
FWIW, if you just bolt out of the box heads on something this test can tell you a lot, for those of us who know better it tells you even more and what can be done with everything else. For all the AFR leg humpers, don't worry about the TFS blending or whatever, it probably didn't make a huge impact.
Bret
For using a stock casting the Livernoise guys did a good job... the Darts aren't bad for cast cast ports that get grosely outflowed by the rest of the heads in the group, I know first hand those heads with some TLC to the guides and a good blending of the valve job can work wonders, I'm sure there is 5ft lbs average in just doing that to the heads.
The interesting part is the BSFC numbers, the AFR is a fuel pig even with less compression it eats gas but does make power with less compression. The GM head is still dam efficient along with the Edelbrock design, and of course the TFS lower valve angle stuff. The Dart numbers are most likely bad here because of the transition from the VJ to the chamber, if that is fixed I'm sure they would pick up.
I agree with them that the Darts in ported form and L92 stuff in would be good to see, the L92's in ported form with a quality VJ would be killer.
FWIW, if you just bolt out of the box heads on something this test can tell you a lot, for those of us who know better it tells you even more and what can be done with everything else. For all the AFR leg humpers, don't worry about the TFS blending or whatever, it probably didn't make a huge impact.
Bret
11-01-2006, 11:54 PM
#33
Interesting... Hello from SEMA....
Just got back from dinner (and a few drinks) and stumbled on this thread.
I'm pleased our almost three year old emissions legal factory replacement heads did so well in this test. Its been so long since we spoke with the mag about this story I had completely forgot about it to be quite frank with all of you.
A few thoughts that quickly come to mind here.
Its pretty obvious by the commentary in the story that the TFS heads were somewhat "ringers" and had the benefit of slightly higher compression which alone could have easily tilted the tables in AFR's behalf...and I have to respectfully disagree with Brett's commentary above regarding the additional hand blending and clean up (potentially) not making much of an impact. Coming out on top in this testing was a matter of single digits...(1% or so)....the way a CNC port blends into (and out of) a valvejob is everything and could easily be worth over 10 CFM unless the transition is close to optimal. The key for you guys is the ability for a company to produce a good flowing production piece and trust me when I tell you that it's NOT easy. You guys would be amazed to know the processes involved to make sure that we do, or at least do our best to (no one is perfect in a "production" environment).
What would a set of AFR 225's done on this same engine ?? (that would have been interesting...)
The AFR pricing was incorrect (they retail for $2274) and dont require any special parts, spacers, etc., etc. and are truly an emissions legal direct replacement cylinder head.
Last but not least is this test would have possibly shown much different results if tested on an inertia style chassis dyno where the benefits of higher airspeed may have had the opportunity to aid in engine acceleration much like it would in your actual vehicle. An engine dyno allows the engine to accelerate at a fixed RPM per second and negates the type of real world gains a small high flowing port can offer you. Much like the benefits a lighter rotating assembly can offer (but difficult to measure on a dyno with a fixed rate of acceleration which is typically 300 RPM per second), they are clearly apparent when driving the actual race car. Also, part throttle power, throttle response, and fuel economy would certainly be stonger with the smaller ports the 205 AFR head design offers....all three of which are very difficult to quantify but much appreciated when you get a chance to actually experience.
Am I making excuses?...Hell no....the results speak for themselves and none need to be made. I'm very pleased how well we did especially considering the company we were in. Also, alot of strong claims have been made the last few months and this type of testing helps bring a little reality to that situation IMO.
Seems you guys just have a bunch more good choices now and the LS market is hotter than ever. If any of you happen to be attending the SEMA show please take the time to swing by and say hello.
Regards from SinCity....LOL
Tony M.
Just got back from dinner (and a few drinks) and stumbled on this thread.
I'm pleased our almost three year old emissions legal factory replacement heads did so well in this test. Its been so long since we spoke with the mag about this story I had completely forgot about it to be quite frank with all of you.
A few thoughts that quickly come to mind here.
Its pretty obvious by the commentary in the story that the TFS heads were somewhat "ringers" and had the benefit of slightly higher compression which alone could have easily tilted the tables in AFR's behalf...and I have to respectfully disagree with Brett's commentary above regarding the additional hand blending and clean up (potentially) not making much of an impact. Coming out on top in this testing was a matter of single digits...(1% or so)....the way a CNC port blends into (and out of) a valvejob is everything and could easily be worth over 10 CFM unless the transition is close to optimal. The key for you guys is the ability for a company to produce a good flowing production piece and trust me when I tell you that it's NOT easy. You guys would be amazed to know the processes involved to make sure that we do, or at least do our best to (no one is perfect in a "production" environment).
What would a set of AFR 225's done on this same engine ?? (that would have been interesting...)
The AFR pricing was incorrect (they retail for $2274) and dont require any special parts, spacers, etc., etc. and are truly an emissions legal direct replacement cylinder head.
Last but not least is this test would have possibly shown much different results if tested on an inertia style chassis dyno where the benefits of higher airspeed may have had the opportunity to aid in engine acceleration much like it would in your actual vehicle. An engine dyno allows the engine to accelerate at a fixed RPM per second and negates the type of real world gains a small high flowing port can offer you. Much like the benefits a lighter rotating assembly can offer (but difficult to measure on a dyno with a fixed rate of acceleration which is typically 300 RPM per second), they are clearly apparent when driving the actual race car. Also, part throttle power, throttle response, and fuel economy would certainly be stonger with the smaller ports the 205 AFR head design offers....all three of which are very difficult to quantify but much appreciated when you get a chance to actually experience.
Am I making excuses?...Hell no....the results speak for themselves and none need to be made. I'm very pleased how well we did especially considering the company we were in. Also, alot of strong claims have been made the last few months and this type of testing helps bring a little reality to that situation IMO.
Seems you guys just have a bunch more good choices now and the LS market is hotter than ever. If any of you happen to be attending the SEMA show please take the time to swing by and say hello.
Regards from SinCity....LOL
Tony M.
Last edited by Tony Mamo @ AFR; 11-02-2006 at 12:36 AM.
11-02-2006, 03:07 AM
#34
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very good article. looks like dart was the only manufacture that didnt spruse up there head before the test. the only true out of the box head for the $. my dart 225's with a 2.055/1.60 valve, 62cc chamber flowed .314@.600 lift, lightly hand ported/finished. so his statements about the darts having great potential after a porter gets a hold of them is very true. although these are THE lowest flowing Darts i have seen so far. just goes to show that flow numbers arent everything. im all about making horsepower with efficiency, cost efficient that is. like someone else said that 90% of us are trying to do.
11-02-2006, 03:15 AM
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oh and just to add to be a smart ***, all of the heads were out of the box. the testers didnt do any modifications to them, ;p. they were sent to them and they took them right "out of the box" all of the heads except the darts were CNC machined so that is what i mean by sprused up as well.
11-02-2006, 09:23 AM
#36
Very little difference between them all...I wonder how well the as cast LS6 heads would have done?
On the dyno charts, what causes the dip @3500rpm with all heads?
On the dyno charts, what causes the dip @3500rpm with all heads?
Last edited by gollum; 11-02-2006 at 09:36 AM.
11-02-2006, 01:26 PM
#39
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Originally Posted by Black02SS
I'll agree with this statement 100%. Maybe someday, someone can do a honest comparison. I'm not saying that TFS isn't a good head, but it is hard to say how well they are when a piece that is tested obviously isn't a production piece.
Brain - Why were those heads used for the test and not a normal out of the box set like the others submitted? If it is to be a "true" comparison, then why not make it just that? Not trying to start an argument, but very curious on this.
Brain - Why were those heads used for the test and not a normal out of the box set like the others submitted? If it is to be a "true" comparison, then why not make it just that? Not trying to start an argument, but very curious on this.
I will speak for Brian on this one since I was a little more involved with Jamie on this project. At the time we were first contacted about the article the production Trick Flow head was late and there were no castings available. Jamie said he would start testing the heads he already had and do the TFS' last if he could get a set of heads before the deadline,this was sometime in may. Most magazines need the articles finished 3-4 months before they hit the newstand. We got the first run of "production castings", cnc'd them and discovered some area's of slight non-cleanup or exposed cast surface in area's of the chamber's. Due to time constraints and the deadline we did not have time for TFS's guys to add more metal to the chamber so it would completely clean up or the head would not have been included in the test. The decision was made at that time to sand out the cast surfaces in the chambers and send them out rather then miss out completely. The heads were shipped on 6-28 because Jamie wanted to run them over the 4th of July weekend. If anything I suspect these heads could slightly underperform due to the fact that, the chamber that was developed with the port and valvejob was not exactly what was in the heads used in the article. Hopefully this will clarify things a little better and help "level the playing field". Nobody tried to pull anything dishonest or send out "ringers" we just ran out of time plain and simple. On a side note, since those heads were built, Trick Flow has added more metal so the entire head CNC's completely, they have also changed the valve cover machining so the baffle's don't have to be taken out and we have developed a better valvejob which flows more through the midlift. Looking back, I wish we could re-run the test with a set of newer production heads.
