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Stock main bolts to ARP bolts?

67Charger

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I'm swapping 440 blocks from my cracked original to a '77 motorhome block. The block was virgin bore/deck, already at the machine shop, line honed, magnafluxed, and bored to .020 for a customer that went to jail and sold the block for the bill. I had the bore upped to my .040 over and decked for Cometics. As I was reassembling it last night, I got the inkling that I shouldn't put my main studs in since it wasn't line-honed with them. I'm running a 496 stroker that makes right at 600HP, and now am at a quandary as to the best path forward.

-50 year old stock bolts (factory torque spec, 85ft/lb?)
-New ARP bolts, (110 ft/lb spec)
-Run the studs. (110 ft/lb spec)

I have all 3 options/fasteners in hand. I know swapping to studs is frowned upon without a fresh line-hone. Remachining is not an option. No time left. Rocky Mountain race week 2.0 is in 2.5 weeks.

What is the least evil option?
 
use the ARP bolts. The higher TQ spec might cause a problem.. BUT, the weaker stock bolts might cause an even bigger issue.
 
I would lean towards using the bolts it was honed with. The caps will break before the bolts will. Cap walk would be the concern
 
Here's what I did: I bought the ARP stud kit and my engine was line honed with the OEM bolts.
I put the studs in and torqued them down to 110Lb/Ft and checked the bearing bores. I found that
my bearing bores were within the tolerance set by the factory, so they stayed in! If the bearing
bores are on the tight side and you put studs in and go for 110 Lb/Ft, you may take all of the tolerance
out and start to take away some oil clearance or worse! Just put em in and measure. Then you'll
know. Having more clamping force on that crank is better for keeping the caps from dancing around
and fretting the joint lines up!
 
Following up.

The cap-walk discussed above was the whole reason I went to studs on the last block. It was happening and leaving significant fret marks at the part.

I put the caps in with the stock bolts, torqued and measured, then swapped the bolts for the studs. Max difference was. 001". My tightest clearance is now ~.0027" in one direction on #3, and .0028" perpendicular to that, with all the rest of the mains measurements between .003 and .0035. ( I wasn't real particular in chasing number to the last .0001 as long as it was in that range). I went ahead and put the crank in with the studs and tightened to 110.

Thanks for the sanity check.
 
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