There seems to different lengths and I have read that you don't want the long ones because it'll bottom out in the head. Can someone give me the correct part numbers for them?

 

ARP # 134-7103 and 234-7202.

 

I got the Comp Cams ones and had to grind some length off, they were running into the bottom of the heli-coil legs. Seems like I removed almost 1/8" but there is still plenty of thread.

 

My comps were made by ARP, I have guideplates and mine fit great.

 

Thanks man! I take it the Pro Series (234-7202) is just stronger....since the specs are the same?

 

Yep, you got it.

 

Cool.

When should the tougher ones be used?

 

I'm no professional when it comes to fasteners, but I would think the high performance series studs are plenty strong enough for the average street/strip car, but if you have the money, why not get the pro series? Its better to have and not need, than it is to need and not have

 

I live by those words!

 

You can throw a machine bushing (ground flat washer) under those if you need to - assuming you're not using guide plates. As long as you have the adjustment range for the rocker and the posilocks and set screws all have enough threads to fit right. I fretted over this for a while when I built my engine cause it was near impossible to measure everything and order the right ones, but I got lucky and guessed right, LOL.

 

I'll be running guideplates.

 

Well , max strength on a threaded fastener into steel is usually about 1.5 x dia so anything close to that will work.