Assembling motor. Need answers!!
- Thread starter DuraLb7Max
- Start date
Yes stock rebuild. I had the heads redone and block honed crank checked...30 over injectors lbz cp3 fass 150 with efi live. That's all for performance. Arp studs. I'm just firing off here sorry if not in order. Obviously none that will take place until the crank is perfected. I'm not moving forward until I get from you guys. Now I will update tomorrow after I talk to my local guy who did head work etc.
I agree. If you had the block line-honed, then plastigauge is fine verifying tolerance (which is what I did).
If the block is stock, then you probably should mic the journals to make sure they are round. Then again, if you are using stock main bolts and torque, they probably are still in spec, so plastigauge is probably safe.
But if you are going to main studs, you usually need a line-hone to get the bores back to round, and plastigauge can mislead you into believing your clearances are fine when they are not.
Everything is in spec just had it measured. Went to a local shop just to make sure. Plastigaged also. Everything is good.
What bolts need to be replaced that are torqued to yield? Rod bolt? Head studs is all I ordered regarding bolts.
The main cap bolts and rod bolts both need to be replaced.
They especially need to be replaced if they were torqued and mic'd and torqued and plastigauged.
They especially need to be replaced if they were torqued and mic'd and torqued and plastigauged.
I dyno'd 580 and ran 12.14 doing almost that exact same "re-build" except for the head studs. I'm old school, and plastigauge worked just fine. Almost 50,000 miles since has pretty much proved it.
Yes, you should use new main bolts when re-installing the crank. But use the old ones to torque the mains down to check your clearances.
Guess I probably should've thrown a rod by now, what with me reusing all the old rod bolts when I redid mine. Oh no!
BTW, who the heck DOESN'T line hone the mains when using main studs?!? You HAVE to in order to open up the clearances, otherwise the crank pinches when you torque the studs to spec. God, I'll never forget the look on Merchant's face when he did that. :hehe:
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It would be a good idea to install new main bolts (not the side bolts) and rod bolts.
But remember to verify if a bolt is torque-to-yeild. Just because it has a torque+angle spec doesn't make it a one time use tty bolt.
But remember to verify if a bolt is torque-to-yeild. Just because it has a torque+angle spec doesn't make it a one time use tty bolt.
Ordered new main/rod bolts. The torques spec for the main bolts are 72ft.lbs. then 97ft.lbs. after torquing to 72 I losen them back up then torque too 98? Of course in the correct sequence. Just making sure you torque then losen.. then torque again? Or can you torque to 72 then straight to 97???
I would torque, loosen, re-torque then turn your angle. I'm getting two ways to do it though,
One is 72lb-ft, 97lb-ft + 60°
Second option is 74lb-ft + 90°
Crossbolt is 52lb-ft
One is 72lb-ft, 97lb-ft + 60°
Second option is 74lb-ft + 90°
Crossbolt is 52lb-ft
You do NOT loosen them up. Do a full pass at 72lbs, then go back over at 97. These are for TTY bolts, not for studs.
It's a burnishing procedure, of course you don't torque to full spec then loosen, only after the first step. Won't hurt anything either way.
I was just making sure it was clear. Should be ok to torque to the first spec then back it off. But I was under the assumption the OP was saying to back off all fittings then torque straight to full torque. It should be done in stages. :thumb: