A-man930

iTrader: (2)

So, I was thinking of ways to bring an old stock displacement LT1 up to gen3 zone. As most of you know, one of the major advantages of the LS1 is the higher-flowing cylinder head design. The LS1 has 18 degree heads correct? So why not throw some Gen1 18 or 15 degree heads and convert them for LT1 use? My questions are... at what point does the different valve angle help performance? Is it one of those "only if you rev it to the moon" kinda things? or does it help across the powerband? And what kind of issues am I going to run into with the intake manifold and headers? Any opinions are welcome!

Ls1Bait

The reverse flow cooling really makes it hard to put gen 1 heads on these motors. There are some people that have done it, they will chime in.

C_Rules

iTrader: (7)

i was looking at the new dart catalog and saw the lower angle heads for the SBCs in there. I was quite curious to see how much power thos things could make.

A-man930

iTrader: (2)

I hear some are harder than others...

1997bird

iTrader: (2)

The LS1 heads are 15 degree valve angle heads. One thing that comes to mind is having enough cubic inches to feed the larger runner heads.

LSXNV

iTrader: (1)

if you want to keep the stock displacement and run large heads, a larger cam would be the only way to go. the trade off is torque. but atleast you get a small block that revs like a motorcycle.

NemeSS

iTrader: (127)

nothing wrong with the AFR heads, they are proven to work,
or some proper ported LT4's with a matching LT4 intake and a 58mm tb

FASTFATBOY

iTrader: (23)

I would stick with a good 23* head, RHS, Dart etc...You can use conventional LT1 type stuff to make them work.

For a 15* or 18* head it requires alot of queer parts to make them work. Like:

Pistons
Valvetrain
Rocker arms
intake
Custom made/fabbed headers


Expensive brain damage above!!


David

SStrokerAce

iTrader: (2)

The GM 15° castings are evil.... 400cfm out of them is possible and they make huge power. You have to build a motor around them, some guys like Mindgame already have and end up with some serious power.

Bret

the_merv

iTrader: (88)

I have only seen 18°..

buffman

iTrader: (9)

IIRC stock LS1 is 15* and they go smaller * then that

the_merv

iTrader: (88)

I got 18° from my research. That's one of the advantages over the LT1. Then again I have heard of 15° also from somewhere..

1997bird

iTrader: (2)

The standard LS1/LS2 has a 15* valve angle head. Trick Flow came out with a 215cc 13.5* higher flowing version. ET Performance came up with a 11* valve angle high flow head in a 210cc,225cc,240cc,255cc, and 265cc runners. The LS7 heads have a 12* valve angle to them. The only one that I am not 100% positive on is the L92 heads. I do believe that they share the LS7 valve angle of 12*.

buffman

iTrader: (9)

just imagine some heads like that on a LT1

the_merv

iTrader: (88)

Cool, nice to know. The L92 Heads are the same as the LS7 Heads, different Valves I believe. The LS6 and LS2 Heads are the same EXACT thing, cast #243.

GIZMO

iTrader: (8)

They have different valves.

the_merv

iTrader: (88)

Yea, I just saw that. The LS6's are sodium filled, like the true LT4 ones.

A-man930

iTrader: (2)

Ok, I was anticipating the pistons, not a problem because I was going to replace the stockers anyways. As for the cam and valvetrain, I am considering a solid roller setup, which would probably include a shaft-mount rockers. I was afraid of these last two though... custom headers and intake, what kinda costs are we lookin' at here? I have always wanted a set of Kooks, which cost $1300 anyways, is that about the range we're talkin'? And the intake... would it have to be a one-off job? or are there intakes lying around that would do the job with some work?

So how high we talkin' about? I don't plan on running an aftermarket computer, so anything above 7,200 is off limits. I'm also looking to save some cash and go with the stock crank (balanced of course, also looking into a cryo treatment and possibly miconite) so I've got to keep it's limitations in mind. Correct me if my logic is off, but would I neccesarily need to have the heads that BIG? I guess what I'm asking is, can I take advantage of a lower valve angle without revving like a motorcycle (that would be cool, I just have my doubts about the drivability of that kind of setup)?

Fire67

iTrader: (3)

First if your not going to go over 7200, forget the different valve angle and forget a solid roller... You'd be wasting your time IMHO as both were designed by the aftermarket with racing in mind, and that means 7200+ revs.

There are lots of carb style intakes available for the 18* and 15* heads, you'd just have to convert one to EFI or run a carb. No big deal unless your gonna go sheetmetal which would be $$$$.

v7guy

iTrader: (1)

I don't think you really comprehend what you're getting into here (I could be wrong). There have been a few guys that have tried, and less that have completed the project. Typically several thousand in parts and labor and they throw in the towel and sell everything.
You can make an off the shelf intake work with some grinding if I remember right. Afterwards you need custom headers, a way to route the steering linkage, valvetrain specific to your project etc. It turns into big money quick.

If your just doing it to do it and have money by all means please do and show us lots of pics. Other than that, there are alot better (cheaper) ways to make the power