L92 DynoJet Numbers Plus Plan B, C, D, E and F...
Originally Posted by Brian Tooley
Wow, 52X HP and 48X torque from maxed out L92's on a 417...I guess I should just close the doors 
I didn't say the heads "don't" work, what I said was the intake valve is TOO LARGE and they are VERY HARD to cam.
People also think the problem with the heads is in the intake, it is in the heads, that is what I said.
The heads are lighter than a LS1 head...and don't hold head gaskets on the spray as well as a LS1 head does....
Some day someone MIGHT figure out a cam that makes 550 RWHP and 500 RWTQ on a 408 like the TFS heads do...but for now they haven't, and it will take a set of heads that flow as good as Charlies or better to do it.
Maybe I should send you guys my "coeffecient of discharge" spread sheet that I created in 1993, then you may better understand velocity around the valve....
I didn't say the heads "don't" work, what I said was the intake valve is TOO LARGE and they are VERY HARD to cam.
People also think the problem with the heads is in the intake, it is in the heads, that is what I said.
The heads are lighter than a LS1 head...and don't hold head gaskets on the spray as well as a LS1 head does....
Some day someone MIGHT figure out a cam that makes 550 RWHP and 500 RWTQ on a 408 like the TFS heads do...but for now they haven't, and it will take a set of heads that flow as good as Charlies or better to do it.
Maybe I should send you guys my "coeffecient of discharge" spread sheet that I created in 1993, then you may better understand velocity around the valve....
While I agree with you that these heads are not the be all and the end all, I think that there is potential in these heads.
IMO they have taught us a few lessons, mainly that "big runners can't produce lowend torque" is not true. Kevin's (WKMCD) car produced 380 ftlbs at 2200 rpm. That is pretty damn stout in my book. And that was with one of the very first cams designed for these heads. While I agree that specing a cam for these heads is different than the cathedral designs, would we really be calling them hard to cam if they had come out first? If we were just getting cathedral heads now and had 10 years of cam research in these (L92)heads, wouldn't it require a whole new approach?
In the few short months that these heads have been used, we have already reached 520 rwhp with a fairly mild cam. Given time I think that they will produce some excellent numbers. Will they surpass a full blown set of TFS/ET/AFR heads? I don't know.
As far as the problem being the heads or the intake. Personally I lean a little more towards the intake because of one thing. Most of the dynos I have seen with the combo like to peak around 6K. That is a little low for an all out motor IMO. I think with a little shorter runner on the intake, peak rpms will rise and consequently so will HP.
These are just my observations so far from what I have read and what research I have done. By no means am I looking to try and start a flame war, just enjoying a good debate and trying to learn.
BTW, any results yet from the big bore TFS heads you are working on??
Originally Posted by WKMCD
That's a little over sensative. I would hardly call a 232-234 114 +2 cam a maxed out build. 
I don't want all of you L92 fans to be over sensitive with me, everyone thinks because the heads flow more air than most cathedral port heads and the fact that the heads have rasied runners that they will handily outpower the cathedral port stuff. The reality of a head with that large of an intake port and that large of a valve is they will make power easier with smaller cams, but then get very hard to cam after that, they are not the "end all be all" that everyone assumed they would be.
I had a set of LS7 heads and L92 heads over 2 years ago, I had a L76 intake and LS7 intake 3 years ago. When we did the TFS head layout 2 years ago I said "forget about making a 4.125" bore head, you can't beat the LS7", then something very interesting happened. When people started putting the TFS 225 "LS2" heads designed for a LS2 on 408's, they were making 30 RWHP more then we used to make with our ported 15 degree stuff, they did flow more air everywhere and did it with smaller valves. That is when I dicided that most of the LS heads probably suffer from intake port reversion at the end of the intake cycle. The clues were everywhere, people where making dissappointing power with the LS7 heads and big cams, I knew the L92's would follow suit. If you put a sheet metal intake on the heads where you can move a ton of air through the heads they will come around, but that is not a streetable combination.
There are a ton of ways to build a combination, a set of L92's and a conservative cam is one way to build good power on a budget, but when it doesn't make the power of the best cathedral port stuff out there then don't be so disillusioned.
Originally Posted by Brian Tooley
What are the chances of more intake duration helping the power numbers? I would say slim to none.
I don't want all of you L92 fans to be over sensitive with me, everyone thinks because the heads flow more air than most cathedral port heads and the fact that the heads have rasied runners that they will handily outpower the cathedral port stuff. The reality of a head with that large of an intake port and that large of a valve is they will make power easier with smaller cams, but then get very hard to cam after that, they are not the "end all be all" that everyone assumed they would be.
I had a set of LS7 heads and L92 heads over 2 years ago, I had a L76 intake and LS7 intake 3 years ago. When we did the TFS head layout 2 years ago I said "forget about making a 4.125" bore head, you can't beat the LS7", then something very interesting happened. When people started putting the TFS 225 "LS2" heads designed for a LS2 on 408's, they were making 30 RWHP more then we used to make with our ported 15 degree stuff, they did flow more air everywhere and did it with smaller valves. That is when I dicided that most of the LS heads probably suffer from intake port reversion at the end of the intake cycle. The clues were everywhere, people where making dissappointing power with the LS7 heads and big cams, I knew the L92's would follow suit. If you put a sheet metal intake on the heads where you can move a ton of air through the heads they will come around, but that is not a streetable combination.
There are a ton of ways to build a combination, a set of L92's and a conservative cam is one way to build good power on a budget, but when it doesn't make the power of the best cathedral port stuff out there then don't be so disillusioned.
I don't want all of you L92 fans to be over sensitive with me, everyone thinks because the heads flow more air than most cathedral port heads and the fact that the heads have rasied runners that they will handily outpower the cathedral port stuff. The reality of a head with that large of an intake port and that large of a valve is they will make power easier with smaller cams, but then get very hard to cam after that, they are not the "end all be all" that everyone assumed they would be.
I had a set of LS7 heads and L92 heads over 2 years ago, I had a L76 intake and LS7 intake 3 years ago. When we did the TFS head layout 2 years ago I said "forget about making a 4.125" bore head, you can't beat the LS7", then something very interesting happened. When people started putting the TFS 225 "LS2" heads designed for a LS2 on 408's, they were making 30 RWHP more then we used to make with our ported 15 degree stuff, they did flow more air everywhere and did it with smaller valves. That is when I dicided that most of the LS heads probably suffer from intake port reversion at the end of the intake cycle. The clues were everywhere, people where making dissappointing power with the LS7 heads and big cams, I knew the L92's would follow suit. If you put a sheet metal intake on the heads where you can move a ton of air through the heads they will come around, but that is not a streetable combination.
There are a ton of ways to build a combination, a set of L92's and a conservative cam is one way to build good power on a budget, but when it doesn't make the power of the best cathedral port stuff out there then don't be so disillusioned.
Originally Posted by Brian Tooley
What are the chances of more intake duration helping the power numbers? I would say slim to none.
I don't want all of you L92 fans to be over sensitive with me, everyone thinks because the heads flow more air than most cathedral port heads and the fact that the heads have rasied runners that they will handily outpower the cathedral port stuff. The reality of a head with that large of an intake port and that large of a valve is they will make power easier with smaller cams, but then get very hard to cam after that, they are not the "end all be all" that everyone assumed they would be.
I had a set of LS7 heads and L92 heads over 2 years ago, I had a L76 intake and LS7 intake 3 years ago. When we did the TFS head layout 2 years ago I said "forget about making a 4.125" bore head, you can't beat the LS7", then something very interesting happened. When people started putting the TFS 225 "LS2" heads designed for a LS2 on 408's, they were making 30 RWHP more then we used to make with our ported 15 degree stuff, they did flow more air everywhere and did it with smaller valves. That is when I dicided that most of the LS heads probably suffer from intake port reversion at the end of the intake cycle. The clues were everywhere, people where making dissappointing power with the LS7 heads and big cams, I knew the L92's would follow suit. If you put a sheet metal intake on the heads where you can move a ton of air through the heads they will come around, but that is not a streetable combination.
There are a ton of ways to build a combination, a set of L92's and a conservative cam is one way to build good power on a budget, but when it doesn't make the power of the best cathedral port stuff out there then don't be so disillusioned.
I don't want all of you L92 fans to be over sensitive with me, everyone thinks because the heads flow more air than most cathedral port heads and the fact that the heads have rasied runners that they will handily outpower the cathedral port stuff. The reality of a head with that large of an intake port and that large of a valve is they will make power easier with smaller cams, but then get very hard to cam after that, they are not the "end all be all" that everyone assumed they would be.
I had a set of LS7 heads and L92 heads over 2 years ago, I had a L76 intake and LS7 intake 3 years ago. When we did the TFS head layout 2 years ago I said "forget about making a 4.125" bore head, you can't beat the LS7", then something very interesting happened. When people started putting the TFS 225 "LS2" heads designed for a LS2 on 408's, they were making 30 RWHP more then we used to make with our ported 15 degree stuff, they did flow more air everywhere and did it with smaller valves. That is when I dicided that most of the LS heads probably suffer from intake port reversion at the end of the intake cycle. The clues were everywhere, people where making dissappointing power with the LS7 heads and big cams, I knew the L92's would follow suit. If you put a sheet metal intake on the heads where you can move a ton of air through the heads they will come around, but that is not a streetable combination.
There are a ton of ways to build a combination, a set of L92's and a conservative cam is one way to build good power on a budget, but when it doesn't make the power of the best cathedral port stuff out there then don't be so disillusioned.
and produce some nice tq numbers, but we have yet to see a large cam produce any numbers with these cams
the combination of cams making the power are not even close to eachother. this last guy has the duration of a TV2, of course he didnt give lift numbers and etc...but it only has 2* of split compared to what ppl were saying you need atleast 6* or more of spilt
this guy with 2* made more power then others with less spilt
so when will we see the rigth combo? could a typical LS cam be the ticket with the right following mods....time will tell
Originally Posted by Brian Tooley
The reality of a head with that large of an intake port and that large of a valve is they will make power easier with smaller cams, but then get very hard to cam after that, they are not the "end all be all" that everyone assumed they would be...
If you put a sheet metal intake on the heads where you can move a ton of air through the heads they will come around, but that is not a streetable combination.
If you put a sheet metal intake on the heads where you can move a ton of air through the heads they will come around, but that is not a streetable combination.
IMO, that's what makes this a great head for the street. Most people want there cake and eat it too, every wants low cost, great torque down low and big HP on top. That's just what they have done here with these sleepers. Excellent manners on the street and huge torque to redline, Great job WKMCD & C_Williams, and to all the others involved!
I'm going to use the L76 head and intake on a 364 FI with a small custom cam. I'm counting on the low end torque and street manners while not on boost and expecting huge gains in HP on the top with 15lbs of air forced down the port.
@0.006 269/277 @0.050 220/228 .598/.613 112LSA +4
Some very good test data on this thread...
Frank
Last edited by StingrayCrazy; Mar 6, 2007 at 12:06 PM.
I'm hoping to end up with some decent numbers with my L92/L76 setup. I'll only be running 10.5:1 CR with -14cc dished pistons and 63cc unported L92s, but I'm throwing a pretty big stick in there. 25x/25x range with .6xx/.6xx lift. It's going to be a daily driver, but a daily driver for a college student is a lot different than that of a non-college student =)
I've got to congratulate you guys for doing something risky and something different and having great success with it. You all did a good service to us at LS1tech.
I've got to congratulate you guys for doing something risky and something different and having great success with it. You all did a good service to us at LS1tech.
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Originally Posted by SVT THIS
I'm hoping to end up with some decent numbers with my L92/L76 setup. I'll only be running 10.5:1 CR with -14cc dished pistons and 63cc unported L92s, but I'm throwing a pretty big stick in there. 25x/25x range with .6xx/.6xx lift. It's going to be a daily driver, but a daily driver for a college student is a lot different than that of a non-college student =)
I've got to congratulate you guys for doing something risky and something different and having great success with it. You all did a good service to us at LS1tech.
I've got to congratulate you guys for doing something risky and something different and having great success with it. You all did a good service to us at LS1tech.
Originally Posted by Quik
id say you need to bump that CR up some to help with that large of a cam or it will be a total dog downlow..shotfor 11.1 atleast
I plan to Dyno my 9.0:1 pig NA just to baseline before I put the boost to it. I bet the numbers will be higher than expected...
Frank
Originally Posted by StingrayCrazy
I plan to Dyno my 9.0:1 pig NA just to baseline before I put the boost to it. I bet the numbers will be higher than expected...
Frank
Frank
Originally Posted by Brian Tooley
they are not the "end all be all" that everyone assumed they would be.
Originally Posted by Brian Tooley
The clues were everywhere, people where making dissappointing power with the LS7 heads and big cams, I knew the L92's would follow suit.
Originally Posted by Brian Tooley
If you put a sheet metal intake on the heads where you can move a ton of air through the heads they will come around, but that is not a streetable combination.
Originally Posted by Brian Tooley
There are a ton of ways to build a combination, a set of L92's and a conservative cam is one way to build good power on a budget, but when it doesn't make the power of the best cathedral port stuff out there then don't be so disillusioned.
The L92s do nothing more than offer one more option in a market that is already rich with a variety of go fast goodies.
The cast iron BBC square port head, is by no means the end all BBC head. Far from it. Does it keep people from using it? Hell no. Make good power with them? Absolutely. Power like Dart pro 1s? Nope. But thats why there is VARIETY. Different tastes, different budgets, etc.
Not everyone wants to shell out the $$ for a set of darts. Or profilers. Or Big Dukes. Or TFS, or AFRs. Heck maybe some want to just try something new. Thats what makes hot rodding cool. If we all did the same thing, used the same parts, what fun would that be?
On another note, how many people out there that ARE making 500 RWHP, with or without cathedral ports, are doing so with as mild a cam as these 2 motors being discussed? That to me says it all. It aint too hard to build a 500 HP motor that chops its *** off and sounds/feels/drives like a race motor. But not everyone wants that.
Maybe we should start a new thread/poll. How many with 402/403 500 RWHP NA, and what head and cam combo. That would give an idea of what it takes cam-wise to make each style combo work.
Teching In
Joined: Dec 2006
Posts: 35
Likes: 0
Maybe we should start a new thread/poll. How many with 402/403 500 RWHP NA, and what head and cam combo. That would give an idea of what it takes cam-wise to make each style combo work.
Thanks for all of the input guys, pro, and con.
Mark
Will someone read post #209 and help me figure out how to get the CR and DCR squared away. I'm not a techie, this was spec'd out for me by SDPC. The heads are milled to 63ccs, .060 cometic, -14cc dished pistons on a 4in stroke 402. I don't want to hijack this thread like others have done so please PM me =) If you know someone who will spec me out a cam (shop or individual) shoot them my way. I appreciate it fellas,
Mitchell
Mitchell
Originally Posted by SVT THIS
Will someone read post #209 and help me figure out how to get the CR and DCR squared away. I'm not a techie, this was spec'd out for me by SDPC. The heads are milled to 63ccs, .060 cometic, -14cc dished pistons on a 4in stroke 402. I don't want to hijack this thread like others have done so please PM me =) If you know someone who will spec me out a cam (shop or individual) shoot them my way. I appreciate it fellas,
Mitchell
Mitchell
-Geoff
Originally Posted by SVT THIS
Will someone read post #209 and help me figure out how to get the CR and DCR squared away. I'm not a techie, this was spec'd out for me by SDPC. The heads are milled to 63ccs, .060 cometic, -14cc dished pistons on a 4in stroke 402. I don't want to hijack this thread like others have done so please PM me =) If you know someone who will spec me out a cam (shop or individual) shoot them my way. I appreciate it fellas,
Mitchell
Mitchell
You can pm me if you're worried about hijacking.
Please! 
On The Tree
Joined: Dec 2006
Posts: 126
Likes: 0
From: Indianapolis, IN
Wilson I've been waiting for someone to try one. Any idea how much CFM it will flow over stock? Any idea how much $$$ they are? Did you see their selection of throttle bodies?
Here's their catalog link:
http://www.wilsonmanifolds.com/shop/...on_catalog.pdf
Here's their catalog link:
http://www.wilsonmanifolds.com/shop/...on_catalog.pdf