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Ive currently been having some oil leak issues with a new motor that was installed in my 1969 Camaro. The mechanics that installed the motor have been having issues as well.

The block is a 400 SBC. I beleive they are using a 350 oil pan on it. It appears to be hitting the front timing cover and not allowing a proper seal. They are telling me they think the oil pan needs to be replaced with one from a 70's chevelle with a 400 in it. That this is the only way to not hit the cross member.

I am wondering if there is any aftermarket oil pan out there that I can buy for this block to help alleviate this issue.
 

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More for Less Racer
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SBC 400 and 350 share the same oil pan.

Only differences are '74-earlier take a thin front lip pan seal, and '75-later use a thick front lip pan seal.

If you have a leak at the front or rear lip, it is eaither the wrong gasket for the pan year, poor installation, or a cheap pan core.
(OR cheap timing cover)

There are sump shape differences between Passenger car, truck, and Corvette pans, but that has nothing to do with sealing up.....just how it clears the chassis.

There are also dipstick location and 1-peice rear main seal differences after 1979, but that doesn'tt apply here.
 

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There are different timing cover to pan gaskets used at inflection point years, if you mix timing covers and pans from different time points you will get leaks. With aftermarket parts you must check what they are built too.

- 1955 through 1974 use a thin 1/4 inch gasket between the timing cover and the pan which has a dip depth of 2-1/4 inch from the pan’s rail to the bottom of the semi-circular dip. The gasket is a 4 piece for each rail and each semi-circle.

- 1975 through 1985 use a thicker 3/8 inch gasket between the timing cover and pan which has a semi-circle depth of 2-3/8 inch from pan’s rail to bottom of the semi circle.

These are likely to have the dipstick on the drivers side, North America. You might find a one piece for these but keep in mind there is no one size fits all.

- 1986 brings the rear seal and one piece pan gasket. These do not retro so you have to be careful. They usually accomdate left or right side dip stick and may be 4 pice or 1 piece.

So when you buy parts you need to be sure the timing cover chin and the pan semi-circle have matching diameters and the gasket set matches the diameters of these parts and satisfies the dip stick location needed and of course the type of rear crank seal which is two piece prior to 1986 and one piece from 1986 forward. You need to be cautioned that two piece rear seal new contemporary manufactured crate motors use the 1975 through 1985 gasket set for the timing cover and pan.

Another leak source on the front is a misaligned to crank timing cover which has the crank seal off center. Another is reusing a damper with wear groves on the seal surface. There are repair kits for this.

So there are bunches of oily traps when building an SBC.

Bogie
 

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Lesson I learned long ago is with purchase of new pan always dry fit. Use a bolt in each corner. No gasket needed. Put a flashlight in the pan first easy to see how well it fits down the rails and that the curved areas front and back are parallel.
you’ll be surprised how bent some pans are.
 
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