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Discussion Starter · #1 ·
witch oil pump setup to use for racing

I know there are two different oil pump assemblies available for the 1.9l engines. The early design has a flat cover with no pressure relief valve. The late style has a pressure relief valve. What style is best for racing and are there any other differences?
 

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Early style has the pressure relief in the timing cover (near the tensioner). Late style has the pressure relief on the bottom pump cover. That's it, no other difference. I suggest if you use the later type pump cover with the pressure relief that you replace the plastic check valve with a metal check ball....the plastic ones have been known to fail.
 

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Discussion Starter · #3 ·
The late style also has the check valve in the cover? Do you know Why? Should I use the relief valve in the side of the timing cover to adjust the oil pressure? I plan to use the early pump cover.
 

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IT Manta said:
The late style also has the check valve in the cover?
The old check valve is still in the timing cover on the newer engines, but the spring is extra heavy-duty to prevent it from doing any bypass function. I prefer to utilize the later style bottom oil pump cover, and make it adjustable for pressure. Just my opinion.
 

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Discussion Starter · #6 ·
Thanks Travis I tried the search function and found the thread. I will use this in the future to start with.

And thank you Rallybob for your input.
 

· Oldpiler
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There is only one oil pump cover you want to use and that's the diesel pump cover. It is cast iron so it won't deflect like the aluminum one and it is much more resistant to scoring. And yes, it is the later style with relief valve. You can get them out of Europe and they are not expensive.

-Dave Clark
 

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Diesel, cast iron, dual stage OP cover

oppositelock said:
There is only one oil pump cover you want to use and that's the diesel pump cover. It is cast iron so it won't deflect like the aluminum one and it is much more resistant to scoring. And yes, it is the later style with relief valve. You can get them out of Europe and they are not expensive.

-Dave Clark
I guess "not expensive" is relative and is not the primary issue in any case. Have you checked lately? They've been out of production for some time now and have become very scarce. :(
 

· Oldpiler
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Well that's a good point. Last time I bought one was 1987 and it was brand new. However, my engine builder (same guy who got me the last one) has a lot of sources and contacts in Sweden and Britain and he reckons it shouldn't be hard to find one, they made so many. Maybe you have to settle for used, who knows, but a used cast iron cover is going to be in better condition than a used aluminum cover.
 

· Old Opeler
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Vauxhall/Opel Oil Pump Cover

Buick/Rover oil pumps are the same basic GM design but a different size. There are castiron plates made to fit between the original cover and the pump body to "renew" the wear face.
Pretty easy to make one from "gauge plate" so that there is a hardened surface for the gear ends to run against.

The other advantage of the Vauxhall/Open PN 3448844 end plate is the steel relief valve as the alloy end plates have PLASTIC ones!

Here is a close-up of the iron end plate:
 

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Save your money on the oil pump stuff. Unless your front cover, pump cover, or gears are really chewed up, just go with the stock stuff. Except for the dry sump system I'll be going with, I've got over 10 year of racing with the stock stuff and no problems. (I might consider the Reese pump if I wasn't going to the dry sump but for ITB you can't do that. The steel cover also looks like may be a good idea, but I'm not sure it would be legal for ITB... then again I would have to go back and re-read the rules looking for a specific clause or loophole that might allow it.)

If you have one of the timing case covers with the pressure relief in it, then completely block it off.. JB weld or spacers (washers) to compress the spring. Then, in the pump cover... the kind with the relief valve in it... use spacers (washers) under the spring to bring the oil pressure up to 60 PSI. If you need a new pump cover you can get it from the OGTS.

You might also consider a pump cover modified with a bolt adjuster to modify the spring tension if you think this might be legal. However, be careful as a long bolt sticking out is vulnerable to damage. If the bolt got hit you might develop a leak and drain the oil from your engine. (If you've read my 2003 wrap-up then you know this kind of problem is now near and dear to my heart.)
 
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