This is the third B20 Block that I've spun rod bearings on. Every time that I've spun them I was on Jun 3's. Anybody know why?

 

what you reving to ....have you had the crank clearances checked .....

 

To 9000 sometimes 9500. The block was done at RS. I can check and see.

 

Who installed the bearings, shop or you.If you, did you check the rod bore size or just the final clearances?Maybe the rods need to be resized? You using stock or arp bolts?

 

Arp bolts . The block was assembled at RS.

 

When are you spinning the bearings? At the drag strip, road course or just street racing? If it's on a road course I might have the answer. Possible oil starvation. Just my 2 cents from a guy who has spun 3 as well.

 

what kind of bearings are u running. OEM, ACL??

i think i might use OEM when i start my rebuild in a few weeks.

 

On the street, but not racing just doing like 40 mph and they let go. Its from reving high at the track and on the street.

 

OEM bearings.

 

go with acl's and your problem will stop.

 

Why will my problem stop?

 

you could also try checking your rods for an out of round condition, you can also use a memmory oil pressure guage, and monitor the oil pressure at high rpms to see if there is a drop or case of oil starvation, if you arent using synthetic in the motors already... (Group IV PAO) then it wouldn't be a bad time to start.

 

I have eagel rods with pink bearings.

 

Is it the same cylinder that keeps spinning or is it different everytime.

 

3rd twice and I believe the forth this time. Also my rist pin cam out and f@#$ed the 3rd cylinder up. How did that happen?

 

whats your compression at and what fuel supplies are u using?. maybe youe detonating all over the place

 

Are you running a vtec oil pump or just the b20 one

 

RS likes to set bearing clearances on the big side (around 2 thou) so it can't be from too tight of bearings. Lack of Oiling or Detonation is my guess...

Suprdave

 

12:1 compression, walbro 255 with RC310 injectors.

 

I'm running a GSR oil pump.

 

Why did the rist pin come out though?

 

those pins are held in by a spiroloc that must have broke

 

b20 and gsr oil pumps are the same

 

you may want to go with a gsr block sleeved. But thatsalot more money and work other than staying with your setup. But the gsr blocks oil squirter help reduce cylinder temps, reducing detonation.

 

I think my shops gonna send my block out and see if it can be sleeved. I'm gonna go with ACL bearings an higher compression pistons.