Idit main cap bolts

Rockmotors

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Hello everyone. I have a 93 factory turbo with 170k miles on it. Pulled the motor to replace the oil pan and remove a broken glowplug. While I had it open, I plastiguaged all the bearings, just for peace of mind. They looked pretty good.
When I replaced the main caps, I followed the specs I had on hand, which was 75, then 95 lb/ft.
Now I've come across the turbo manual supplement that calls for an additional 45 degrees torque angle after that.
I can't find any other reference to this.

Should I pull the pan and retorque? Also, Does anyone have specs on main bolt diameter and length so I can check them for stretch? Or should these bolts just be replaced after having been torqued several times now? Once from the factory, and twice by me, plus another if I pull them to measure and retorque.

I kind of feel like leaving it alone, since I know the straight 95 lb spec is plenty good for n/a motors w/ aftermarket turbos, but I know I won't feel good about it down the road.
 

IDIBRONCO

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The extra 45* seems to be on the excessive side to me. You'd probably be in the 140 lb-ft range or so.
 

IDIoit

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please explain "replace main caps"
i hope you used the ones that came with the engine
 

Rockmotors

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Sorry, I just meant when I put them back. I see how that's easily misconstrued now, lol.

Only thing I changed out is the oil pan.
 

Rockmotors

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Idibronco - that seems much better. It would be pretty in line with the what I've read about the turbo motors getting 110 on the head bolts.
 

The_Josh_Bear

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But with angle-torque you'd be using stretch bolts, eh? If so, they cannot(or at least should not) be re-used as they permanently stretch during the angle phase.
I've never heard of a standard fastener using angle torque, but I have zero schooling on the matter. Just what I've read as things come up to fix on one of my vehicles.

It seems strange to me that IH would use the angle torque method for main caps but not for the head bolts.
 

IDIoit

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But with angle-torque you'd be using stretch bolts, eh? If so, they cannot(or at least should not) be re-used as they permanently stretch during the angle phase.
I've never heard of a standard fastener using angle torque, but I have zero schooling on the matter. Just what I've read as things come up to fix on one of my vehicles.

It seems strange to me that IH would use the angle torque method for main caps but not for the head bolts.

the head bolts are not designed for "torque to yield"
i suspect the main bolts are the same, i cannot confirm.
however,
every engine ive built, which is like 5 idi's have,
torque em down to 75 and 95. and they have been fine.

i did 125 on main studs and girdle, and screwed that one all up.

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IDIBRONCO

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every engine ive built, which is like 5 idi's have,
torque em down to 75 and 95. and they have been fine.
That's good to know. I'll bet that the Manchero puts out a little bit more power than most of the engines on here.
 

typ4

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Because this is so wrong I just called my machine shop, he said absolutely do not go over 96. he has seen the supplement, says its very wrong info, puts the bolt very close to failure torque.
I listen to this guy when he talks.
 

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