I had my 427 crank shaft machined and it was ground to .30 on the mains and .30 on the rods. I am told by some...that this is too much for a high performance engine (450 HP). They say that there's not much hardened surface left and that the larger bearings hold heat more. What do you guys think? Thanks!

Assuming you meant .030, that's nonsense.
You could take .100 off at that power level.

You can have it nitrided which will make bearing surface hard again smile.gif

Originally posted by BillsCamino:
Assuming you meant .030, that's nonsense.
You could take .100 off at that power level. =
That pretty much covers it ;)

You can actually have a stronger crank ground .030 or whatever if the radius is done properly.
We used used to have small block 350 cranks "offset" ground .100 from 2.100 to the old 2" rod journal size with almost all the material taken off the inside or main side of the rod journal & this is the weakest part of the crank to make a stroker before stroker cranks became so inexpensive.
This is like grinding the journal .200 if you were doing it on center.
383's are another good example. 400 stroke with a 350 main size.

Dont alot of the NASCAR and NHRA guys use a 1.88 rod journal now ?

Yes, it's a Honda rod size to lower bear oil film speeds or something like that to up the hp just a schosh at high rpm.

And when I mean high, I'm talking like 8,000rpm AND above!!

Tells you just how tough parts are..

pdq67

My 454 is .020 under on the mains and .030 under on the rods..

Some of the NHRA Pro Stock teams are experimenting with 1.772" diameter crank pins and using Aurora/IRL rod bearings in DRCE 500 cu. in. blocks. These are very short stroke/long rod combinations therefore there is plenty of pin overlap and crank strength is not sacrificed.