Tolerances

[Don Frelier]

As for a '78 400 or a '70 400. The specs will be the same for the engines

The 400 came out in 1972.
Just an FYI.

 

[69Bee]

That post wasn't directed towards you. I appreciate your help! Would the 70s chrysler manual cover the torque specs on a 400 from a 78 cordoba? I didn't see a specific one for the 78.

Yes, motor-wise, it will still be the same.

 

[69Bee]

Its just a 78 400 bored 40 over with kiethblack 240 pistons, crank turned .020 on mains and rods, and a stock roadrunner cam not looking for a race motor just a cruiser for pokeruns

The pistons will need to be spec'd to KB info, not OEM. The materials and pistons are different, and react to heat differently.

Go to this website: UEM Pistons and look your pistons up for clearance specs. The KB pistons will use a different top ring gap too, but the info sheet (found on their website) will assist in that aspect also.

 

[beanhead]

I would never tell someone to NOT get a service manual, but some of the information isn't necessarily the final word anymore, especially when it comes to torque specs...the part manufacturer's recommendations out-rank the manual. Things like aftermarket parts, better (ARP) fasteners, etc may have different specs than factory.
Same goes for bearing clearances...it's common to run them looser than the book calls for depending on the builder and the intended use, with no problems.

 

[66Satellite47]

I would never tell someone to NOT get a service manual, but some of the information isn't necessarily the final word anymore, especially when it comes to torque specs...the part manufacturer's recommendations out-rank the manual. Things like aftermarket parts, better (ARP) fasteners, etc may have different specs than factory.
Same goes for bearing clearances...it's common to run them looser than the book calls for depending on the builder and the intended use, with no problems.

Bean, you make the excellent point that FSM torque specs are for the factory bolts. I should have been more clear about that in my earlier post. When a person starts to change parts/aftermarket the ball game changes. The example, ARP bolts are a different material than factory, therefore have different tightening requirements. Main bolts, rod bolts, head bolts should all be torqued to the bolt manufacturers spec.