I agree, those heads aren't made to flow over .650" lift at the most. What ever that person posted was crap....here is some "real-world" numbers for people to look at...

https://ls1tech.com/forums/showthrea...=l92+head+flow

Have fun!
Adrian

 

they would help but as with anything matching a cam to it will get you more

 

Can someone tell me if the "bare" L92 heads are a machined aluminum casting only or do they have valve seats and valve guides installed?

 

The L92 heads as sold by the dealers should have seats and guides installed.

Richard

 

Thanks Richard. Also, I have been doing searches for 2 days, everyone talks about the L92 truck intake and the carb intake but I have yet to find any part #'s or pics of either. If I have overlooked it i'm sorry. Everyone basically doesn't seem to care since most people here have a car and are concerned about an intake that will fit under the hood. I am mostly interested in using the carb intake. Any info would be appreciated.

 

I have the truck intake in my garage if you want me to look at anything for you. I have a pile of stock stuff out of it.

 

Carb intake will be out in about a month. GMPP is making them.

 

25534401 (carbed L92 intake)

 

 

The truck manifold is actually a fair amount better on power in the mid range, and a touch on the top end. However, the car intake fits better for most applications and the truck manifold is butt ugly

 

Wizard,

Are you talking about the L92 specificly or truck intakes in general. From what I read it seems they have a little better low end but peter out top end and that is on a stock motor. I wouldn't think that would be any good for any mods unless this intake doesn't follow the track record of the other truck intakes.

I have one as it is all that is available for my L92 stroker motor and I was assuming it was garbage for my application.

 

Ok, I seen where someone said that a FAST intake will fit the L92 heads with a little love, would it be worth it to do all the loving on the fast or just get a truck intake?

 

The only places I saw someone say the fast might fit with some work got shot down I thought.

 

Hmmmmmm???

 

My reliable source said I'll have my intake within 30 days!??

 

Yes, this is specific to the L92 intakes. The truck manifold is good. The cathedral port truck manifolds are not as good as the c/p car manifolds.

 

It's gonna take more than "a little love" to mate the FAST manifold to the L92 heads, and even more to make it work good with them. I know the FAST manifold is better than the productions cathedral port manifolds, but I'd be impressed if it's really any better than the L92's

 

Thanks for the info.

 

good luck with that i have a good source for getting parts too but damn GM wont relase the ****. The intake we need was supposed to be out back in may.

 

They have been saying 30 days since May. I'm sure this will turn into a winter project!