SBC crank clearance?

[rod]

am going to redo an old SBC which had a Lot of bearing clearance [3 on R & 3.5 on M, 50 wt oil 90lbs PSI OLD]
crank is std - clearance. I want to turn it 10-10 and start new. what is the best clearance for a race engine, good rods, 7K max. no more high PSI or heavy oil. Cleavite P bearings
Thanks Rod in AZ

[Henrys Toy]

Originally Posted by rod

am going to redo an old SBC which had a Lot of bearing clearance [3 on R & 3.5 on M, 50 wt oil 90lbs PSI OLD]
crank is std - clearance. I want to turn it 10-10 and start new. what is the best clearance for a race engine, good rods, 7K max. no more high PSI or heavy oil. Cleavite P bearings
Thanks Rod in AZ

Good morning Rod and to all,
I'm pretty confident if you can get your Main and Rod clearance's between .002 to .0025 you should be in a good zone. Running to 7500 rpm with 5/ 30 wt. oil 60 to 70 lbs. of oil pressure will also be safe.
Have a good day, also have the crank magged for cracks before having any work done is also a good idea.

Respectfully,
Henry Kunz 1534 H/SA

[richie 2]

clevite H series bearings r a good thing too. be aware the H series rod bearings r marked for upper/lower orintation.

[ron mattson]

What Henry said is spot on, that’s exactly what I shoot
for clearance and pressure wise, things are happy there
and will give good performance and longevity!

[Alan Roehrich]

I like 0.002" on the rods, and 0.0025" on the mains, and I prefer the King bearings. If you go higher than that on clearance, you probably need to use thicker oil, ie. 20W50.

[rod]

thanks all for the help. funny to think back on how ideas used to be. you can just imagine the cam/dist gear milling away trying to turn an oil pump shimmed to pump 90 lbs.!!
Rod in AZ