Stang's Bane

iTrader: (22)

Brian,

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??

Brian Tooley Racing

iTrader: (13)

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.

WKMCD

iTrader: (2)

HELP!!! I've been hijacked! Again.

FRDnemesis

iTrader: (19)

Brian Tooley Racing

iTrader: (13)

Yeah....but it keeps your post at the top

Sorry, again

Quik

iTrader: (7)

i seen the price for a set of TFS 225 and its a healthy chunk of change. so to compare the L92 to a TFS225 and price difference if you lose 30hp then so be it. for max build yes money plays no rule. but for a budget it seems like the L92 are working within the margin

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

StingrayCrazy

iTrader: (5)

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

SVT THIS

iTrader: (27)

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.

Quik

iTrader: (7)

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

StingrayCrazy

iTrader: (5)

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

Quik

iTrader: (7)

and youll probably run a cam that isnt a NA setup either

edcmat-l1

iTrader: (10)

^^^I dont think anyone is debating that fact.....

I wouldnt call either of the two motors in this thread disappointing.....


I thought you said earlier the HEADS were the problem?


I dont think anyone here is 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.

Mean 69

I think that would be an excellent idea. In addition, if possible, the various dyno plots that could be used to compare power across the board (and torque) to get a "feel" for civility. I know it is generally secondary in the hot rodding world, but some of us are getting older, and excellent power, with excellent drivability is becoming (more) important.

Thanks for all of the input guys, pro, and con.
Mark

SVT THIS

iTrader: (27)

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

White_Hawk

iTrader: (3)

It is going to be REALLY hard to get a DCR that high with a cam that big. Why do you want such a big cam? Most people who are around 500 have done it with cams in the 230's.

-Geoff

edcmat-l1

iTrader: (10)

Need one more spec. How much out of the hole is the piston. Thats pretty important.
You can pm me if you're worried about hijacking.

SVT THIS

iTrader: (27)

I chose that cam based on SDPC's advice...

edcmat-l1 sent you a PM!

WKMCD

iTrader: (2)

Talk me out of it. Please!

cybernco

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

edcmat-l1

iTrader: (10)

DAMN!!! Hard to talk ANYBODY outta that!