rod berring clearance/oil type

Have been lurking here and find alot of great info,Hoping someone can help me with some questions;
1. What clearance do you recomend on rod berrings?
2. What grade oil do you use,multi grade or single grade?
3. Is there a operating oil temp that is recomended,or does anyone heat the oil to get correct clearance on the berrings?
We are new to blown alky racing and want to start on the right foot. We have a KB/1471 that is all new,any help to keep it right would be GREATLY appreciated.The guys we race with are not blown alky racers and their combos are different so we get alot of different answers to questions we ask. Would like to here from the guys that have been there,done that.
Thank you kindly John

 

as for clearances..call bae or kb

as for oil type..we run 50wt till it gets real hot out then go to 60wt


as for oil temp.. we always fire the car warm it up we always like to have some heat in the motor


hope this helps
second wind racing..Dave Lowe

 

we run a kb olds 540 in a promod boat, we run 3.5 to4.0 on mains and 3.5 on rods,[brooks alumimum] very mild tuneup[ 1550hp]we run a drysump with 50 wt oil,preheat to 160 deg before first start of the day.

 

Thanks Guys, when refuring to heating the oil I should have said pre-heat the oil befor it is poured into the motor. My motor guy says the bearing clerance should be gauged when the oil and motor are at operating temp,not at room temp.
I do not fully understand the term "multi grade" oil,I understand for example a 20/50 oil will act as a 20 weight untill it warms up,then having a 50 weight viscosity when it gets of temp. I just do not see how an oil can get thicker as it gets warmer,I would guess just the oppisite.
I have looked at sae 50 and 20/50 side by side and there is quite a big differance between the two.
Thanks for the info so far........................... John

 

Multi-grade oils work like this. Say 20w50. This oil has the thickness of a straight 20 wt oil when cold, and the thickness of a straight 50 wt when hot.
It does not get thicker when it heats up, it only gets as thin as straight 50 wt would be hot, or as thick as straight 20 wt cold.
Hope this makes sense

 

john111,we have a heat element in the tank,and on the other engine [wet sump] a heatstrip on bottom of pan.don,t try heating the oil before you put it in the engine.160 degree oil is tough on the hands[ouch thats hot]