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minendrews68
08-25-2015, 04:53 PM
My son and I are working on a LS1 engine, he bought it from a friend of mine that owns a salvage yard in a nearby city. We've pretty much got it apart because we want to rebuild it (new bearings, gaskets, rings etc.) I was talking to some local friends and they were telling me that the LS engines head bolts were not suppose to be used again and when reassembled there was a special way to torque them. Can you guys lead me in the right direction as what to expect when rebuilding this engine? Another said its best to replace all the sensors and not to use aftermarket ones. I've never worked on LS engines just small block, so any help would be appreciated.

Thanks,
Carl

2yellow69
08-25-2015, 05:00 PM
Correct on not reusing the head bolts. Throw all but one of them away. Take the one you save and cut 4 vertical grooves in it 90* from each other and use it to chase the threads in the block. They are torque to yield head bolts and are one time use. Buy ARP head bolts that you can reuse pretty much forever. All of the other bolts are reusable except for the damper bolt. Again, buy an ARP.

minendrews68
08-26-2015, 05:26 AM
Any idea how to torque these? I've heard stories about torqueing these to a certain ft/lb then go a certain degree, or something like that. Like I said, these engines are new to me..

TheParker
08-26-2015, 07:32 AM
http://www.ls1.com/forums/f35/torque-spec-sheet-143688/

Typhoon1015
08-26-2015, 08:29 AM
Throw away the stock head bolts, you can get new GM bolts to replace but they are torque to yield and are one time only at ~50 a set. ARP makes head bolts that you can reuse. Pro-comp also has a cheap set of head studs that are reusable ~70 bucks.

I have reused stock head bolts in a non-boosted applications, but don't recommend for others (i was aware of the risks and was ok future issues arose from it)


Also, its worth the $$ to buy this book and learn about the engines a bit.
http://smile.amazon.com/dp/0760335435

How to Build and Modify GM LS-Series Engines (Motorbooks Workshop)
by Joseph Potak

cactuss4
08-26-2015, 10:03 AM
Just note that many aftermarket head bolts (non stretch) require a re-torque when heat cycled. Lifting sets of heads because one fails to do this is an issue. One reason I like to use the OEM bolts in my applications is that you torque and are done.

Tory