Engines dont run so great w/o oil...

[John Milmont]

I found this out first hand for a Labor day high speed auto-cross at the Wilwaukee mile road course. My brother and I were co-driving his beautiful '89 Firebird and have never ran this type of circle track/infield road course configuration before. Those long, high-G turns in the oval sections of the track starved the engine of oil and it wasnt long before we spun a bearing. Its interesting how the engine somewhat slowly lost power the eventually died. We knew things were bad when he went to go start it again (it turned over slowly) and heard the distinct sound of a rod flopping around.

We haven't opened the engine yet, but i can guess its not good. My question to the brain-trust that is this forum is; whats the usual procedure and cost for repairing this mess? How far can the damage go? The engine is a gen-1 sbc and has a totally stock bottom end. I'm wondering if it would be cheaper to just get a new short block and move over the nice bits like the heads and what-not. I know that the all of the bearings have to be replaced, but does that mean that the bearing surfaces in the roller rockers are going to be ruined too? maybe valve guides? what else?

 

[Jac Mac]

Oil ( & air ) would still have been getting pumped, so minor surfaces like guides & rockers would probably have been getting enough.

Crank & at least two rods will be toast( burnt/bent/cracked), possible valve /piston /head contact on cyl with spun rod brg, chance of damage to main brg that fed toasted rod as once brg goes oil pressure drops @ the adjacent main.

Everything in short block will need a real close inspection as metal spray will have gone everywhere.

I would go for the replacement short block and look 'REAL HARD' at anything in the lubrication circuit before reusing it. Oh & if you might even think about doing it again buy a decent oil pan & pickup.

 

[Randy V]

I'd get a Goodwrench Shortblock right from Chevrolet.. Relatively inexpensive (I paid $1300 for a long block a couple years ago)..

GM Parts Direct: Your direct source for Genuine GM Parts

While you're at it - look into a good pan from Louvered Tray, Aluminum Windage Tray - Champ Pans by JR Manufacturing - you may need to do a little fab work on the exhaust crossover, but it will be worth it. CP100RR is the part number (from memory - so double check)..

This pan was designed and proven on one of my racecars..

 

[John Milmont]

Yeah, that's another thing - oil management. We were thinking of dry sumping the engine. There was a guy out there with a baffled pan and accusump, and he said he was really tapping into the accusump; that made me think about dry sumping and just be done with it.
Is affordable dry sumping possible? There seems to be a huge selection of pans out there for sbc, but I don't see any complete kits/systems...

 

[tom pritchett]

I keep hearing that the dry sump is the way to go. If that is correct, why is it chevy has had soo many problems with the dry sump 427 in the z06? My buddy at the track is on his 3rd engine because of this out of oil problem in the dry sump system. I know porsche has it down, but maybe chev doesn't quite have it right yet.

 

[John Milmont]

My buddy has a dry sump system in his FFR cobra and its worked flawlessly. Hes running the 32 valve mod motor out of an '07 mustang cobra. I guess its pretty rare to
have that engine in that car. I believe he has a 2 stage system and has never had a problem.

It looks like dry sumps are really not to difficult to plumb either; I thought you may have to tap into an oil passage and then plug the original pickup, but apparently, you can just get an adapter that goes where the filter mounts and that becomes the oil inlet.

I dont know if this is true, but i hear that the z06 has a quasi dry sump.. in that it has an evacuation pump that goes to a reservoir but feeds back into into a standard oem style pump...

 

[Jac Mac]

I dont know if this is true, but i hear that the z06 has a quasi dry sump.. in that it has an evacuation pump that goes to a reservoir but feeds back into into a standard oem style pump...

Yes & that might be the cause of the problems in the post above. While it serves the purpose for spirited fast road type driving, when actually under race conditions it probably gets enough oil suspension that it literally runs 'dry'... begins to pump aerated oil.... and its all over Rover.
More than one scavenge section plus a decent tank designed to aid in seperating air/oil are all part of a good dry sump setup.

 

[Dave P]

I agree with Randy. I have used Champ pans for years and never had a problem.
On our old street stock engines we used to avoid the high volume pumps , because they would suspend too much oil in the heads with a stock oil pan. We lost several engines before we just put a high pressure spring in the stock pump.
Spend money on a bolt on pick up. I have had the stock pickups fall out :shout:

 

[Tom]

Serious and well instrumented testing on stock Corvettes w/LS7 engines indicates the fault actually lies in the oil tank. Lacking any significant baffling, as well as marginal capacity, the tank is likely to feed aerated oil to the pressure pump in certain situations. So while the LS7 drysump (pan, pumps etc) may not be the total state of the art, they are up to keeping a Corvette running with a better/retrofit oil tank.

I further understand the gerotor pumps in the LS7 may not be up to extended running above 7000 rpm.