Novaray64

I have a LQ4 engine out of a 02 silverado I am planning on using a turbo 350
on the block one of the bellhousing bolts is not drilled just wanted to check
and see if there would be any problems drilling and taping the block


thanks

twinturbo2

iTrader: (16)

i have read if u drill that hole its a oil passage just leave that one bolt out imo

Rat Chevelle

It is the water jacket IIRC.
But it will be OK if you leave it out, I remember running a BOP TH400 behind a 350 for a couple years using only a couple bolts with no adapters whatsoever and I never had any problem....
I know that was a terribe hack job, but then that's what I had and I used it, and even to my own surprise the thing held pretty well. So with only 1 bolt missing you shoud not have any problem.

twinturbo2

iTrader: (16)

k water passage my bad

_BANDIT1_

I know it's an old thread but maybe this will help to someone:

Yesterday, I drilled a 6th hole on my LQ4 with 8.5mm drill bit, 17 mm in depth and I didn't reach water passage.
Then I cut a thread M10, about 13mm in depth.

Now TH400 fits perfectly with all 6 bolts and 2 alignment pins.

LS1MCSS

iTrader: (18)

There wasn't really any reason to go through the trouble of drilling the block. Thousands of people, including me, are running transmissions with 5 bolts in them.

74novacustom

Agreed, me included, but its his block and if it helps him sleep at night, more power to him.

Gray86hatch

iTrader: (83)

The bolts only hold the block to the trans they are not carrying the load the dowels do this.

Tim

bczee

iTrader: (12)

I would question how much metal is left. The water jacket can't be must deeper.

With any stress, heat cycle or whatever.. might be a possiblity of a crack happening..

Just a though !?