Hey guys,

I'm building an LT1 right now. Unfortunately, when I bought the engine I was told it was a 1996 LT1. When I assembled the engine, I torqued the heads down using torque-to-yield specs for '96+ LT1 head bolts. I later realized that the timing cover that is on my engine is 1995 specific so that can only mean that my engine is a 1995 LT1.

So here's the question: I have to undo the head bolts and retorque to the non-TTY specs (three passes increasing to 65lb from what I've read?) and while I'm at it I'm going to replace the bolts with ARP head bolts.

So the question: If I remove one bolt at a time in sequence, then immediately replace that one bolt with the ARP bolt and snug it down, move to next bolt, repeat, would I have to replace my head gaskets since they've been compressed? The engine has never been started and there's never been any compression put onto the cylinders. Can't I just replace each bolt one at a time, snug them down one at a time, and then once all are snugged down start the torque down? Do we really have to replace the head gasket just because it's been compressed once?

 

You can remove them all at the same time and replace them...or you can do them one by one if you really want to, it makes no difference.

 

But can I reuse the head gasket? That's the main question I need to know. I'm being told that I need to buy a new head gasket because it's been fully compressed and can not be used again. I don't see why it makes a difference because it's just going to be compressed again as soon as I retorque everything back down especially since the engine has never been used, no oil in the system yet, no compression on the chambers, etc.

 

Yes, you need a new head gasket. The metal gasket is soft. Think of it filling in all the uneven torque distribution and gaps, although in theory, there should not be. The best way to put it is if you have the time to take everything back apart and the costs associated with that, go ahead. I prefer to do the job right the first time.

 

You are dealing with a lot of variables here. Just cause it has a 1995 timing cover doesnt mean its a 1995. Also im pretty sure that the sequence and torque would be no differant than any other year lt1 because all the heads and blocks are interchangable. Somebody correct me if im wrong.

 

What did you torque the heads down to? Honestly I don't think it matters too much, but I would like to know the answer as well on weather or not it's ok to reuse a head gasket that has just been torqued down and never run before on a new motor. You aren't resurfacing the heads or block and it was never run so I don't know why you couldn't use them again.

 

I would leave the heads alone. Seems like a lot of unnecessary work. There is no reason you cannot use the torque/angle method for tightening the bolts. It is actually the better method.

 

You can reuse the gasket, unless it has been heat cycled it will be as good as new.

 

The timing cover that's on it is a 1995-only timing cover, so how could it be another year?

Also, we followed the method that was in the Hayes for 1996 which was the torque-angle method. I've since been reading the threads on here and saw Shoebox's comment about the bolts being exactly the same just a different method of torquing down and that they are not TTY.

But is it OK that I reused the bolt? I have a set of ARP bolts sitting here ready to go in, so if it'd be better to use those... I just want to make sure that I do it right before the engine goes back into the car - a lot easier to do things now than do it when the engine goes back in.

 

The ARP bolts would be preferable, IMHO. Make sure you are using sealant on them and oil under the heads/washers.

If it is really important, you can confirm the year by the partial VIN on the block.

 

Alright so just to confirm: Do the ARP bolts with thread sealer and lubricant/oil, buy new head gaskets, and use the torque-angle method?

 

Re-use the gaskets, you have not hurt them at all. I will repeat that again, it does not matter that you have torqued down the heads on the new gaskets, you can remove the bolts and replace them with the ARP's with sealant(#2 Permatex) and torque them to 65ft/lb.

The one time use bolts have the washer built into the head and are gray in color, the older reusable bolts don't use a washer.

 

Thanks for your help guys!