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Author Topic:   HV oil pump
akadirtracer7
Member
posted August 23, 2004 11:55 AM
What the general thought on hv oil pumps to use or not to use.


dirtbuster
Member
posted August 23, 2004 12:03 PM
Depends on what your clearances are. If you are running the engine a little looser then yes id use one. Also if you are running remote filters or oil cooler then i would definitely use one. There is no need of having excess pressure but you also need the volume if the motor calls for it to keep oil flowing past the bearings to cool them. On our mod with oil cooler we have about 75psi cold and will idle 35 or so after a race. On the track racing it will run about 65-.

[This message has been edited by dirtbuster (edited August 23, 2004).]

akadirtracer7
Member
posted August 23, 2004 01:21 PM
0015 to 00175 on the rods and 2 to 2.5 on the mains. been running 15w40 with hv pump and pressure dropping at the end of the straight from 60 to 40 psi.I think its pumping to the top end, had this motor in a factory stock with a different pan no problems.Last week it was dropping to 20 psi. at the end of the straight.I was running 20 deg more of water temp 200* and 200 rpms more.Pulled the pan and checked bearings everything looks good. I put a stock pump with 20w50 and will see if theres a difference don,t want to waste a motor with a few races left.


dirtbuster
Member
posted August 23, 2004 02:16 PM
That seems a little tight to me on the rods. mains are prob good at .0025 but i'd look more for around .002 or so at the rods.
Also make sure the crankcase is vented good so that pressure doesnt build and keep oil from draining back into the pan. IS it a stock pan or race pan? Also what kind of oil filter...


akadirtracer7
Member
posted August 23, 2004 06:57 PM
Its a circle track pan .got 2 breathers and been running these clearences on this motor for 4 years now with no failures.Filter is a wix.


engineman
Member
posted August 24, 2004 04:54 AM
I agree with dirtbuster.... .002 on the mains is about right, anything less than .0017 is kinda tight, I run .002 to .0025 on the rods in a SBC dirt motor,and I run no less than .0017 and no more than .0025 on the mains....and I try to keep it around .002 on the mains. everything Dirtbuster is telling you is right on track, and I wouldnt be afraid to run a stock volume pump, but I would shim the bypass spring a little. JMO

Mark T.

------------------
Mark's Racing Engines

(903)883-0196

www.northtexasracing.com

engineman@northtexasracing.com


rico 08
Member
posted August 24, 2004 01:40 PM
I always run a stock volume pump,mine's .002 on the rods and .003 on the mains(loose),it's a one peice rear main seal motor so i went a little more on the mains,works good for me.


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