Generation III Internal Engine - Head bolts for LM7 5.3




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PACKETFOCUS
04-24-2012, 01:07 AM
What head bolts should I use on a LM7 5.3 with 6.0 heads for boost?

Gasket recommendation?


PACKETFOCUS
04-24-2012, 01:10 AM
Not exactly what year, but crank is 12552216, block is 12567392, 24x wheel

PACKETFOCUS
04-24-2012, 01:19 AM
Hmmm... .857 NARROW FLANGE crankshaft. Any problems with this working with a glide or turbo 400? I read somwhere on here that I needed a different flange crank .875?

Seems to me all I need is a flexplate and LS to TH400 converter


PACKETFOCUS
04-24-2012, 01:36 AM
found this is what I need to run a Lm7 with a Th400 or Glide

Crankshaft spacer# GM 12563532..Bolts# 12563533

salemetro
04-24-2012, 01:40 AM
What head bolts should I use on a LM7 5.3 with 6.0 heads for boost?

Gasket recommendation?

OEM 6.0 Head gaskets and arp bolts...studs it ya wanna spend the $$$, but it all depends on how much boost ya wanna throw at it. 15-18 should be no problem with a good set of bolts.

PACKETFOCUS
04-24-2012, 01:44 AM
yeah this is just a budget setup to play around with a turbo on a stock shortblock. May try to push it to 20lbs for a couple passes.

Got two lm7 shortblocks on a good deal so I gotta backup hehe.

Thanks for info. Didn't know if Ls9 head gaskets would help or not.

wildcamaro
04-24-2012, 11:40 PM
Ls9 head gaskets are 5 or 7 layer and made for boost I would use those if possible.

chrisfrost
04-25-2012, 03:47 PM
There's a Youtube video of a silverado 5.3L pushes it up to 24lbs. it's a dyno vid and supposedly is crankin 2000ponies ,,,,,,,course it would'nt last too long but a cpl passes should be no problem depending on mileage of You're engines.