John Souder wrote...
>As oil warms up it gets thinner, and the pressure will drop as a result
>of this as the oil finds it easier to slip past bearings etc. Ths
>pressures you quoted are fine, but I would suggest you go for a 10-20
>mile drive to get the oil up to working temperature and note the
>pressures again.
>
>John
Caution Teckie.
Burn before reading.
When I built my first hipo alpine engine, I was pretty carefull about
the clearance specs and the like on the engine, but I was a tad dissapointed
in the resultant oil pressure.
My oil pressure works like this...
Start the car, cold 1200 idle, OP is 75 PSI.
Let the engine warm up to 190 deg F (at)1200 rpm idle, OP is 50 PSI.
Take the car for a 15 minute "normal" drive, RPM>2000 OP=70-75.
Come back to the garage, OP (at)1200 RPM is 30 PSI.
Take the car for a "hard" drive, RPM>2000 OP=65-70.
Come back to the garage, OP (at)1200 RPM is 20-22 PSI.
Even with my adjustable oil pressure valve, it looks like
there were enough crevices for the oil to seep internally to
make the relief valve run full closed when the engine was idling/hot.
Dan Walters spoke recently on a customers engine, he was able to get
great oil pressure across the board, even without going to the trouble
that I went with bearing clearances.
Whats the deal?
He said that the oil pump protrudes through the block into the main oil
gallery. This would allow a loose fitting pump housing to leak more oil
then it ought to, back to the sump.
His solution has to goo the pump housing during installation.
Seemed to work, because the oil pressure is short of miraculous on this
engine.
When my engine comes out of my car "very soon", i am going to figure out
how to o-ring it to prevent the afformentioned.
Jarrid Gross
This archive was generated by hypermail 2b30 : Tue Sep 05 2000 - 10:41:03 CDT