Schmitty

iTrader: (11)

This is my set up:

-1989 GXL
-s5 6 port motor
-Rebuilt 15,000 miles ago, stock ports
-When rebuilt I left the oil jets in the E-shaft stock and used an Atkins solid oil pellet. Also,the o-ring in the front cover was installed correctly
-Camden EFI supercharger kit for the 2nd gen
-Front cover was tapped on the engine, oil pan was removed instead
-OMP is still bolted to the motor but the outputs are bolcked off, I run premix
-I'm running 20W-50 and the oil is less than 100 miles old with minimal fuel dilution
-My oil source for the supercharger comes form under the oil filter via a racing beat oil press/temp gauge adapter.

Before I installed the spupercharger kit I had soild oil pressure right where it should be, 30psi at idle and above 60psi when on the throttle. After I installed the kit I retained these pressures but I felt that my supercharger wasn't getting the oil it needed... it ran hot (hot enough to melt the omp lines, which is why I've eliminated the OMP for now)...

I had a tee coming off the oil pedestal gauge adapter so that I could run my aftermarket oil pressure gauge and still have a source for oil to the supercharger but I think that this set up was too restrictive and not enough oil flow was getting to the supercharger. I took the tee and extra pressure sender out and plumbed the oil feed line directly to the adapter. After this change, when the oil was cold the pressure was normal, 30psi at idle and 60+ under load but when it warmed up the pressures dropped to about 15psi at idle and about 45psi above 3k rpm. I'm not really too sure on those numbers since I read them off the stock gauge, halfway between 30 and 0psi at idle and halfway between 45 and 60psi under load... but my stock gauge really wasn't too far off from the aftermarket gauge I had.

This makes me think that the drop is because now the oil is flowing well to the supercharger and not because my oil pellet in the e-shaft is messed up or that o-ring in the front cover is wrong or broken... could that be true?

Are the pressures that I'm seeing dangerously low? I've read that 20psi idle and 50psi 3k rpm and up are the safe minimums.

Will the 80psi regulator that racing beat sells help this situation or do I need a different oil pump too, like a turbo pump or something? I'd rather find a different soultion that doesn't have me taking off the oil pan and the front cover again...

any Ideas?

Thanks,
Rob

Schmitty

iTrader: (11)

Well, I guess I'll update my own thread in case some one is searching for the same issue...

I talked to the previous owner of this kit and he said that his stock gauge read low (15 to 50psi instead of 30 to 60+psi) while the supercharger was installed on his car but he never had an after market gauge to compare with... He ran the kit for 10,000 miles with out the engine seizing up so it seems like any added wear from the low oil pressure is not catastrophic... I guess only time will tell on my engine. Next time I take the oil pan off I'll probably upgrade the pressure regulator though.

Any thoughts?

noshow

its good that it isnt causing any noticeable damage, but i would upgrade the regulator personally because of the increased stress on the motor because of the forced induction and also because unlike piston motors we cant run synthetic oils that lubricate better so we have to rely on high oil pressure.

Schmitty

iTrader: (11)

I'm not running and OMP so I can run synthetic. I will probably switch over next oil change...

Slow Rotor

My engine builder advised me against synthetic. He said it's still better to run the normal oil as it is thicker and doesnt get squeezed out of where it needs to be under boost

Aaron Cake

iTrader: (1)

Upgrading the regulator won't make a damn bit of difference.

Running synthetic is fine.

You can run it anyway even if you have the metering oil system.

He's stupid. Ignore him.

Sounds like the supercharger is bypassing too much oil. The NA oil pump doesn't move as much volume as the much larger TII pump so if you pull a 1/4" line off of the oil filter and dump it back into the pan, you're going to have low pressure. The supercharge probably isn't internally restricted like turbochargers are so the flow is likely much greater.

Honestly I wouldn't worry about 15 PSI at idle. The engine will be fine. 45 PSI at 3K is fine as well. However it should be increasing as the RPMs increase. At some point it should be showing 65-75 PSI.

General rule is 10 PSI of oil pressure per 1000 RPM.

Be glad you didn't do the Weber jet mod with the NA oil pump. I did, and thus my engine makes 4 PSI of oil pressure at idle. At some point I'll have to pull the front cover and swap in a TII oil pump.