diablizzard

iTrader: (8)

has any body had problems with the GM Performance parts head bolts not being able to hold any torque. I was just trying to torque them down at 65 ft/lbs and they were stretching. I even used one of the flexing wrenches to watch it. and it wasn't making it to 60. before any body asks, I did step it up in incriments. I've used them before on my truck engine, and that was at 80 ft/lbs. this is about my millionth issue with this project.

Mkos1980

iTrader: (8)

I assume this is on an LT1 as the LS engines are TTY. On another note, I have used the GMPP bolts on various Gen 1 builds with Vortec heads. Zero Issues.

Apeiron

What's a "flexing wrench", and how do you know they were "stretching"?

diablizzard

iTrader: (8)

the flexing wrench is the one with the pointer, and as you torque the wrench flexes. It has a big guage on the end, kind of like this one. http://www.summitracing.com/parts/SHC-944690/ here it's called a beam torque wrench.
If they don't hold the torque, then they must be stretching. At least that's what I think.
I think i may have gotton a bad batch of bolts.

Apeiron

"Beam torque wrench" is the correct name.

What does "not holding torque" mean?

diablizzard

iTrader: (8)

I guess my terms are a little off. as I was trying to torque with the beam torque wrench the torque wasn't going up like it should. It was sitting below 60 ft/lbs as I was turning it. That's how I can explain it not holding torque.

five7kid

iTrader: (14)

You are also lacking specificity. What "GMPP bolts"? Have a part number?

What engine? LT1? LS1? Hope not Gen I SBC, since you posted in the LTX and LSX forum.

diablizzard

iTrader: (8)

That's my fault, This is on an LT1 the part number for the bolts is 12495499. I have a build started on proposed lt1 build.

Guest

Use a clicker style. Those beam styles are cheap junk. Then go to 75, and finish the job.

Apeiron

Nothing wrong with a good deflection torque wrench properly used, and unlike a clicker you can see the difference between running and static torque.

diablizzard

iTrader: (8)

I used 2 other clicking torque wrenches. the first was a brand new craftsman, the other was a snap-on.

I'm hearing that these head bolts I got are superceded tty bolts. that's just something I don't understand why they did.

Apeiron

I still don't understand what "not holding torque" means.

diablizzard

iTrader: (8)

My term is a little off. The torque wasn't steadily going up when I was trying to torque the bolts properly. It was hovering below 60ft/lbs as I was twisting it. If it was "holding" to me it would slowly go up and not just "hover".

Apeiron

How did you prep the threads? Remember you're compressing the head gasket too so the torque will increase less slowly than you might expect.

diablizzard

iTrader: (8)

The treads on the bolts came with a thread sealer on them, and the treads in the block were cleaned. There wouldn't be too much to compress from 50 to 65. some of them torqued properly on the other head, so I had a feel of how it felt.