Don Terrill’s Speed-Talk

Gentlemen:

I have a set of Trick Flow Steel Connecting Rods currently in my engine. This is a 565 BBC and the bolts are ARP-2000

Would anyone happen to know what the bolt stretch is for these rods? I realize we can call ARP and get a generic number but the engine builder would like to have the specs from the rod manufacturer. I do have a call in to Trick Flow but they no longer sell rods and I thought I might come here and ask since I'm not sure they'll have that info. BTW, I do not have the spec card that came with the rods.

Any help would be greatly appreciated.

What's the UHL?

The first thing is to ask yourself how many times have these bolts been torqued up?

I never use the same rod bolts over if they have been torqued up more than 5 timed in a motor that will go to 7000 rpm and some builders I know use a number of 4 , and yes this includes the first time the bolts where torqued up when the rods where made!

mag2555 wrote: ↑Thu Nov 09, 2017 1:49 pm The first thing is to ask yourself how many times have these bolts been torqued up?

I never use the same rod bolts over if they have been torqued up more than 5 timed in a motor that will go to 7000 rpm and some builders I know use a number of 4 , and yes this includes the first time the bolts where torqued up when the rods where made!

How does it make any difference in a non torque to yield application? When the bolt is loosened it should return to the same length it was before it was tightened.

Engine builder is replacing the bolts. Would just like to know what stretch was recommended by the rod manufacturer. I have a call in to Trick Flow but so far no response. Was hoping someone knew something about these rods. I don't know the UHL, if we can't find out what was recommended then he'll measure the bolts and see if ARP can supply the correct bolt and they might have an answer for us.

Cashflow wrote: ↑Thu Nov 09, 2017 3:40 pm Engine builder is replacing the bolts. Would just like to know what stretch was recommended by the rod manufacturer. I have a call in to Trick Flow but so far no response. Was hoping someone knew something about these rods. I don't know the UHL, if we can't find out what was recommended then he'll measure the bolts and see if ARP can supply the correct bolt and they might have an answer for us.

Bolt stretch is a factor of the bolt not the rod. Different bolts in the same rod will need a different stretch to have the bolt at its optimum tension.
If the builder is replacing the bolts then the new bolts need to be brought to their specified stretch or touque and then the rod id needs to be checked for correct dimensions.

I can almost guarantee that those rods are re-labeled and just sold by trickflow so maby try and find out who made there rods at the time. from there you might have butter luck looking up some specs/info. if its a popular size it will most likely still be sold today as somebody elses rod