kdm123

I recently started racing a C4 Corvette. The had been raced for many years in SCCA pro racing. I haven't made any mods to it.
I noticed that in several corners I'm getting oil starvation, with the gauge going below 20 psi. I had my mechanic check the oil pan and pump and everything is working correctly.
What I don't get is why I'm having this problem when the car has been raced for years as is and without any dry sump.
I'm also having trouble figuring out how to fit a dry sump system into the engine bay.
Anyone else race a C4 and have this same issue?

Nokones

No issues anymore.

kdm123

Who makes this dry sump system? thanks

Nokones

Aviaid Dry Sump system. The system required significan modification to the frame and the redesign of the passenger side motor mount and reconfiguring a couple of header tubes. The entire front drive pulley system had to be reconfigured. Lingenfelter did the engineering and installed the system along with the new motor.

zrtman1

What pan is on it now? I believe Moroso makes a race pan for the C4.

Nokones

Kdm123 - your inbox will not accept anymore PMs

kdm123

Quote from Nokones,

"I was using a Canton road race pan and the new motor only lasted 1 1/2 Optima events. On Sunday during the first session on the Hot Laps segment, the engine let on the third lap from oil starvation. The only thing that I could use was the heads and the EFI setup. The block was a new Brodix All Aluminum and nothing was salvageable. A Dry Sump system is not cheap but, it was the best way to prevent an engine from starving oil in high G turns and or under hard braking.

It is very difficult to fit a Dry Sump in a C4 because of the design of the chassis and the tight fit of everything under the hood. The entire passenger side frame and motor mount had to be reconfigured/beefed up and the headers had to have a couple of the tubes rerouted. The dry sump oil pan was custom built."

kdm123

I'm not sure what oil pan I have on my car. The car is with my mechanic and I'm waiting for him to get back to me.

I spoke to the car's previous owner again and he said he never had any oil starvation issues. He said he never lost a motor because of oil starvation. He raced the car for several years in the late 90s and early 00s in SCCA World Challenge.

Before I noticed the problem, the car had done one race weekend with the previous owner, and two track days with me. I had my mechanic look at the bearings and he did not see any evidence of damage.

Nokones

It was explained to me that the tires have something to do with it these days because we can take a tad more Gs in the turns. That will make the oil in the sump to slop around more.

There is a reason why the oil pressure will drop to 20. I've seen that on my L98 years ago during Open Track Events at Thunder Hill. It had to be sucking air or the pressure would stay up at 50 or so. It will be a matter of time where the bearings will not like that anymore.

Another problem I had when the Brodix block was built, the engine builder put in a High Volume High Pressure Oil Pump. I was told that the High Volume was a big No No. It was explained to me with the High Volume Pump there is a lot of oil up top and doesn't get a chance to drain back down to the sump and when you are in a hard braking or corner situation you may be sucking air along with the oil and since the oil is low it could very well be foaming in the sump thus, you're just going to **** off the bearings.

The road race pans only have a 7 quart capacity, not enough capacity to keep a High Volume Pump from sucking foam or just air. A Dry Sump will always keep a constant supply of oil to the pump thus, never starve during hard braking or corner situations.

Also, I was told that Road Race Pans can be your worst enemy than a stock Oil Pan.

kdm123

I did think about the tires providing more g forces, but I noticed the problem even on a lower-performance tire I use.

db2xpert

Accusump....

freaknbigpanda

Are you driving harder / faster than the previous owners? If you aren't pulling more g than the previous owners it should be OK. Also the track makes a difference, long sustained high g turns are obviously going to be harder for the engine to maintain oil pressure

kdm123

Nope. The last time the car was driven prior to me purchasing it, it was driven in a race by Kim Baker, the guy who in the late 80s won the SCCA World Challenge in a C4. He won the race. Since then, I have done two abbreviated track days, and after that my mechanic checked the bearings and found no evidence of wear. However, I can clearly see the oil pressure gauge dramatically dropping.

I plan on installing an Accusump and driving it as is w/o a dry sump. I will have my mechanic check the bearings again after the next race. I don't really know what to do, but I don't really want to spend $5K plus installing a dry sump yet.

I've considered running an LS motor. I'm not sure if that really helps though. The LS6 in my '03 Z06 has never shown any oil starvation issue and I know they put a lot of engineering into the oil pan on that motor. However, I also have never run any really sticky tires on my Z06.

Nokones

In one of the recent discussions, there were some C5 ZO6 owners discussing the oil starvation with their LS6s without a dry sump. One of the engines was a Lingenfelter built LS6

seamus2154

The batwing C5 oil pan does well till you get sticky tires and coil overs. Many have done well with this compromise pan, till you get slicks and suspension. I have a c6z now which still has issues because it is not a true dry sump. A true dry sump has a pump and pulls vacuum and a much better baffled tank, like an ARE or a peterson tank. Everything else is a compromise till you reach it's limits. A true dry sump is the only insurance if you are pulling good G's.

freaknbigpanda

What sort of Gs do you have to be pulling for the ARE system to be worth it? I tracked my stock c6 z51 for years without issue on street tires pulling about 1g, I have a c6z now.

freaknbigpanda

Does it matter if the oil pressure gauge drops during turns? What is the lowest safe pressure?

zrtman1

Yes -if gauge drops your sucking air.

Was he over filling the pan? That does not make any sense... nothing has changed since previous owner ran it?

Did your mechanic check oil pump pickup? They are pressed onto pump and I have seen them work loose and some even crack. Both are rare but does happen. On sbc would always braze the pickup on oil pump - just remember to pull spring first.

Personally I would add an extra 1/2 quart and run it with accusump off to see if it helps (at least a couple laps). Accusumps are great - I run one on my C5, but more of an emergency/rare oil pressure loss. Not really meant for oil pressure loss on every lap imo...

We always ran Moroso pans in our customer/lease oval track engines.. Never any problems with starvation. Bearings always looked excellent at end of season. We felt Moroso were a little better than Canton but we were also a Moroso WD. Both are baffled and gated. Yes dry sump is ultimate, but pricey for a weekend hobby..

larryfs

I ran an extra qt oil in my 1996. Never had a problem in 10,000 track miles, on Hoosier A's