Was wondering which head was better for carbed use ...Cathederal or rectangel port. It seems most are after the 243's which are cathederal I believe. That probably answers my question. Any info would be appreciated.
Thanks Steve

 

If I were starting from scratch all over again, I would use the L92 heads. They work like crazy, are cheap. I just don't see a down side.

 

L92 heads flow as much as my tea 243 heads and are way cheaper.

 

running a carb'd LY6 in my truck...its a 6.0L that has rectangular ports....and it putts around nice, but turns into a beast when I nail it!

 

Thanks for the replies........ I can get new L92 heads from Chevy for 383 a pc. But then would probably need springs. My new cam will be 612 lift. The factory springs say max 570. Have not looked anywhere else,maybe someone has a set of these already done they are trying to get rid of. Of course I'm not quite ready for them yet. Anybody got some cold air ........if so send some my way. Steve

 

here too....damn its hot. But I have to say...even with the heat my truck is still a monster. Playing around a few days back...I wound up 1st to about 5k and hit 2nd really hard.....had to get out of it quick as it 'bout swapped ends on me!

I swapped out the springs on mine as my cam has .610/.617 lift and got the gold dual spring kit (.650) with titanium retainers, locks, and all from Patriot.

 

I sort of figured you for a smaller port volume keep the velocity high type guy. I was a little suprised to read you talking this way about the bigger heads.

To the OP, cam selection is important with the L92 heads. The intakes vastly outflow the exhaust. You can go into some of the FI sections here and read till your eyes bleed about mid range torque and cam selection with the L92 heads.

Also L92's require a 4 inch bore, so 6.0L and larger only. They also require an L92 intake. That might have a lot to do with the popularity of the 243 heads.

 

I think my L92 heads along with the cam choice and intake choice wound up coming together as a great combo. So far no draw backs that I can find. Motor makes a lot more power then my old iron head 400hp 383 sbc....and surely weighs less!

some pics of the heads and intake

 

Can I get a part # on that manifold please. Cant view from my phone.

 

That is a pretty good looking intake.

 

Sure...from the GMPP catalog its: #19244037

yeah I planned my combo around it so to speak as I wanted carb'd...but with L92 heads and a carb....most available were single plane. When I found this intake in the 2009 catalog...I waited. Then it was in the 2010 catalog...impatient I had calls into 2 Chevy dealerships w/parts guys watching for it for me....and I finally got to order one in mid June 2010. I'd guess I got one of the 1st available and was just under $500.

 

I'm in the process of building a 6.0 with ls3 heads. What do you guys think about porting these heads. I'm going to run a 617/624 cam. Do you think its necessary, worth the effort? Will it actually help or hurt?