Don Terrill’s Speed-Talk

carmakerevive wrote: ↑Tue Oct 24, 2017 10:48 pm got a restrictive filter element between the pump and engine? or between the feed and pump? Sounds like restriction or cavitation somewhere.

Racerrick wrote: ↑Tue Oct 24, 2017 11:20 pm slow the pump down. too much pump rpm

Straight8 wrote: ↑Tue Oct 24, 2017 11:54 pm Suction hose collapse maybe? From tank to pump.

MadBill wrote: ↑Tue Oct 24, 2017 11:54 pm I expect your HP is well into four digits, but 100 + psi still seems way high. We run ~ 60 in our 750 HP/8300 RPM SBF road racer..

Where are you tapping in for the pressure signal and could you perhaps tee in a second sender immediately after the relief valve to see if there is an excessive restriction?

MTENGINES wrote: ↑Wed Oct 25, 2017 1:33 am I have seen large main or did clearances cause this. In excess of .028r.030m. It hears the oil up real quick. What's your side clearance in the rods and litter clearance. ?

cjperformance wrote: ↑Wed Oct 25, 2017 6:15 am How well is your oil deairated? I have had to chase a similar problem but in a shorter term rpm combo BUT in a wet sump. A long length of high pressure clear tube in this instance showed the problem instantly. This was in a ford clevelend and was already using an external main feed line, substituting this for clear hose looped past a video camera showed it up.

Racerrick wrote: ↑Wed Oct 25, 2017 9:49 am the first poster has way too much pressure for a sbc! 65 is all you need. the oil is too cold to flow properly. if all the obvious solution don,t help the pump most likely cavitating. increase the pickup tube diameter. use suction rated hose. slow the pump down. smaller pump. I prefer Motorcraft brand 7.3 diesel filter fl1995. it is readily available, the newer ones are very efficient, 95%@18 microns and still flows 20gpm , burst is 200psi and 30gram capacity.

Newold1 wrote: ↑Wed Oct 25, 2017 10:45 am Talk to the guys at Peterson who have speed record car experience. They will be able to better analyse and help you research the issue or they can contact some racers in that arena who have experience with this type of issue. Some simple thoughts, was pump pulley matched to sustained rpms, how far and what is routing between pump and tank, where is oil pressure sensor mounted in system, is the oil pressure measured mechanical or electronic. what type , size and brand # of oil filter, are pump inlet lines reinforced or hard wall, what is actual oil being run, have you tried raising oil temp to about 160 degrees, is engine using spring oilers in addition to piston squirters, what's the windage configuration. Just throwing out some thoughts.