88silvergt

iTrader: (8)

Is it possible to put the LS3 heads on a 5.3? Have heard it may have issues with valve to block clearance on the small bore 5.3 and want to see if anybody knows for fact. Is there anything like thick head gaskets that would help? I'm wanting to build a 600rwhp pump gas motor with a 76mm turbo. Thanks for any info.

parks450

iTrader: (17)

Anything is possible...is it worth it? No, have your stock heads cnc'ed and call it a day.

97badass

iTrader: (8)

Gmpp has the l92 small bore heads, but basic run of the mill ls3 heads will NOT work

beatmeofficer

correct me if I'm wrong but i believe the bore size is not sufficient to support to design of the heads. additionally you will end up having to go with a LS3 intake and bunch of other pains in the ***. There's no reason why you can't get your stock heads worked and make that kind of power... seems like people are doing it all the time now.

88silvergt

iTrader: (8)

Ok, guess its a no go.

sidewayz28

iTrader: (24)

no........

Mako77

seems like a pita

Matt0matic

https://ls1tech.com/forums/generatio...-tfs-215s.html
The Ls3/L92 heads require a min. of 4.00" bored (6.0 LS/LQ and up).

97badass

iTrader: (8)

i guess you dont pay much attention, i was refering to the SMALL BORE heads, but even then i doubt they will work on the 5.3s super small bore. there is virtually no worthwhile information in the link you provided.

WS6sleeper

iTrader: (1)

600rwhp will be a breeze with any heads you use going boost!

69cutlassrkt

mast motorsports also has small bore heads. Cost would be $2000 for a bare set. And your 5.3 would need bored to 3.900

88silvergt

iTrader: (8)

I will just use the stock longblock. When it wears down I will get the 5.3 heads cnc'd and cleaned up. Hopefully a good turbo cam in this stock longblock and 12lbs of boost should get me to my goal.