savage1

Hope this is helpful, there has been a lot of posts with different suggestions on torque for the crank bolt.

Spoke to ARP today and they recommend 235 ft lbs torque on their
harmonic balancer bolt (using ARP moly lube).

Again this is for the ARP bolt P/N 234-2503 with their lube.

By the way, the vendor who I bought the ARP bolt from would not recommend a torque number but they suggested to clean the threads
and install dry.

savage1

frodo84

hmmm...the info I have from them says 196 ft/lbs with ARP lube....

savage1

yeah I am aware that they have advised different numbers.
forum member Vettenuts was also told the 195

savage1

lucky131969

Well, my curiosity got the best of me, and I called ARP. The tech guy claims the balancer bolt torque spec is the same as stock for a P/N 234-2503. Believe it......or not.......

vsocks1

So which is it?

vettenuts

That is one reason I called them several times prior to doing my heads. Their tech support just seems to be all over the place. I just installed mine last week at 190 lb-ft. Oh well, never came out in 11K miles with 190.

savage1

WTF



Maybe what he meant by same as stock was the initial torque of
the used bolt to 240 ft lbs before replacing with the new bolt?



savage1

savage1

Time to email the president of ARP and ask him to clarify

savage1

lucky131969

Kinda weird isn't it? ARP is THE name in performance bolts, but no consistency in a torque spec. I wonder if anyone has actually measured the torque on a factory bolt after the 140 degree pass?

By the way, if you would have just bought a new GM bolt.......you'd be done by now...

savage1

Yea, that may be the case but if I didn't have a GM bolt which no one seems to be able to get to go 140 degrees, I might not have spun my pulley.

I feel pinning and ARP bolt is the way to go. I will see if I can't get something from ARP to eliminate the confusion. Will post what I find out.

savage1

lucky131969

Hmmmm..I not sure where the trouble lies with getting the bolt to 140 degrees. I pinned my balancer when I installed my supercharger, and installed a new GM bolt. Zero issues. I'm not saying that getting it to 140 degrees was easy......I had to use a 3 foot piece of pipe on a 1/2 drive

savage1

I don't know either but I have read a lot of posts that said they couldn't get there and called it quits short of the mark. Maybe they didn't have the correct tools and an appropriate cheater bar. Maybe it had something to do with the crank turning?

I did not install mine last time and I did not have it pinned. This time I will do it myself and pin it. I am not suggesting that the vendor who did my install did not torque it correctly but somehow my pulley spun and the crank bolt is loose.

savage1

corvettebob1

150lbft is plenty to hold your balancer if it's pinned.
The whole reason GM and everyone else is using the higher number is they have to in case the balancer is not pinned.
The virtue of pinning stops any relative motion between the balancer and the crankshaft therefore the bolt is only holding it against the shoulder and not used in twisting retention.

vettenuts

I have been very frustrated with ARP the last couple of years. It used to be the tech support was the guys who tested and knew what was going on, but now it is just someone who looks it up on the computer. I got three different values for my head stud kit when I called, I finally asked to speak with someone who was familiar with the testing to obtain the value.

Bill Curlee

Well,,,,,,,,,,I just installed a Powerbond damper (pinned it to the crank) and used the ARP bolt (was told to use 235 ft/lbs by ARP.) on my 02 Z.

Its in there with 235 ft/lbs, and I used a MONGO 3' 0-250 ft/lb Torque wrench and a 24" strap wrench to hold the damper stationary.

All I can say is that, it torqued up easily without any issues and if it can hold up to the hell I put it through, it not going to break.

BC

vettenuts

Just got mine back on the road today

Bill Curlee

EXCELLENT!!

BC

'VETTE PHASE

I didn't have any trouble getting 140*.