Choppy_Idle

Wanna put LS3 heads on a LS6 engine, in regards not to buy another pair when i go to big displacement after stock bottom end will die after a while...

They only one i found with enough meat on them to go to 300+ intake port volume might be the Mast 240's or is there any other available to put on a 3.89 bore and can be also used later up to 4.25 bore with machining to new specs?

Greetz
Ron

G Atsma

LS3 heads REQUIRE at least a 4.00" bore due to valve size.

AnotherWs6

iTrader: (17)

^^^^Nope - it's been done.

G Atsma

Cylinder notching needed? Clue me in, I was not aware it could be done. "The word" has always been that LS3 heads needed a 4" cylinder.

Choppy_Idle

I won't tell that, when i wasn't sure it exist in reality:

http://www.mastmotorsports.com/colle...oducts/ls3-240

Greetz
Ron

JoeNova

You can put smaller valves in an LS3 head and make it work. Its been done.

G Atsma

AHA! Smaller valves! I knew with OEM valves there was no way.

Darth_V8r

iTrader: (4)

Those mast small bore heads are great. plus your intake options get far better with LS3 style ports

1bdbrd

iTrader: (12)

Yeah but for the price of the Mast small bore heads you can get some nice MMS heads or Trick Flows for the same price or slightly cheaper.

big hammer

The mast small bore ls3's are a serious piece. Need rpm on a 5.7L engine. Ls3 ports have a lot of intake options for under the cowl of an fbody too.

Gm also makes a small bore ls3 head but they're mediocre IMO.

Choppy_Idle

^^^ This, i know, especially with 240 intake runners, maybe 225 is here the best bet, but there is none available...

I will loose tq in the lower range and gain hp in the upper compared to 225, but with stock bottom end i will or can't rev higher, there is a compromise...

Can someone provide a link to the GM small bore heads?

But i didn't expect enough meat to go up with them to 4.2+ bore and 2.2 valves or something like that?!

Greetz
Ron

Darth_V8r

iTrader: (4)

I'm usually the first guy to recommend mamo heads. I don't think there is a better head for a 346 than the mamo 220. OP seemed set on rectangles. You really do have more intake options - like medium length runner fast. Hell the stock ls3 intake is a great piece and easy to modify.

Choppy_Idle

Yes, u are right, want let the door open for the future to have more options to choose from, maybe the LS3 peripherie market is bigger then LS6 cathedral port, rectangular rules... lol

And yeah, seen Tony's site and pics on it, i'm deep impressed, for sure...

Greetz
Ron

00pooterSS

iTrader: (40)

How about MAST small bore for now, pull them and big valve them later.