Tin Indian

There has been a bit of confusion here as to the proper cyl head bolt torque values. Will you please take a look at the procedure below and comment:

Thanks,
Ron
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LS1 CYL HEAD TORQUE PROCEDURE:

Prep the block surface and head bolt holes. Everything must be very clean

1. If possible, clean all bolt M-11 holes with a M11 x 2.0 cut Thread Tap.

2. Spray GM 12346139 cleaner or brake cleaner into the bolt holes. A pistol bore brush works great and will clean any left over material. Re-spray and clean the cylinder head bolt holes out with compressed air. Repeat as necessary.

ALT. METHOD: If no compressed air is avail; Run a narrow piece of hose, connected to a Shop-Vac into the bolt holes to suck out cleaner and debris. Repeat as necessary.

3. Install the cylinder head onto the locating pins and the head gasket. The right and left head gaskets are not interchangeable.

NOTE: All M-11 bolts must be new. They are not re-useable. The narrower M-8 bolts may be re-used.

NOTE: Before dropping any of the head bolts in the holes, lightly lubricate the [face] of the bolt head that comes into contact with the cylinder head with ARP ‘Lubro-Moly’ or equivalent. Do not put lube on any of the bolt threads. Lubing the bolt face will make for more accurate torque readings and will let the bolts stretch evenly.

4. Install (not tighten) all the M-11 cylinder head bolts (short and long).

5. Apply a 0.20” band of ‘Locktite’ GM P/N 12345382 or equivalent along the threads (lengthwise) on the 5 M-8 cylinder head bolts. These are the narrower of the bolts.

6. Install (not tighten) the M-8 cylinder head bolts.

NOTE: Refer to the bolt torque sequence chart prior to tightening any of the bolts.

7. Torque all M-11 bolts in an inside-out sequence to 22 ft lbs. (first pass on all M-11 bolts)

Mark a straight line on the heads of all the M-11 bolts for degree angle reference.

Tighten all M-11 head bolts to 90-degrees. (second pass on all M-11 bolts)

Tighten the (8) M-11 long bolts another 90 degrees. (third pass on M-11 long bolts)

Tighten the (2) M-11 short bolts another 50 degrees. (third pass on M-11 short bolts)

The lines on the M-11 long bolts should have turned a total of 180 degrees, the M-11 short bolts 140 degrees.

8. Torque the remaining (5) M-8 head bolts that go along the top of the head to 22 ft lbs. in the proper sequence.
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[ December 29, 2001: Message edited by: Kimchee and Rice ]</p>

jmX

Looks like what I've had in my head install doc all along on http://ls1.fbody.com

<img src="graemlins/gr_chug.gif" border="0" alt="[chug]" />

Tin Indian

Thanks Jon.....

jmX

Oh yeah, if you buy new m8 bolts, which I do, they come with the loctite already applied. You only need to add it if you reuse loctite.

I also never have lubed the head of the bolts either...with the torque angle method I dont see how it'd matter either way.

Brother J

One minor suggestion: run a piece of hose, connected to a shop vac, into the bolt holes to suck out debris. I just happened to have some `1/2" OD clear hose and noticed some gunk being sucked out after using compressed air to blow it out.

[ December 29, 2001: Message edited by: Brother J ]</p>

Tin Indian

J....

Very VERY good tip....

Tin Indian

ttt
any other comments?

GeorgeC

That's pretty much the same way I've always done mine, except I never used any lube under the bolt heads...