1098 & 1275 Oil Pans-- Same or Different?

[theleisure]

Are oil pans interchangeable between these two motors?

 

[Hap Waldrop]

No, not even close, the only one that interchanges is the 948 and the early 1.75" main journal 1098, all else are unique to themselves. I know this because we always ran the Winer Circle race oil pans, and found out years ago, what would interchange and what would not, even though the 1098 10CC motor and the 1275 has the same main jornal sizes the main caps and oil pans are different.

 

[Dug]

Take a look at this past post.
You may get your answer there.

https://www.britishcarforum.com/bcforum/ubbthreads.php/topics/628750/Re_oil_pan#Post628750

 

[theleisure]

Thanks! I'm going through the list as i get ready to swap a 1275 in for my 1098 (10cc) and I wondered if I'd be able to reuse the chromed oil pan that the PO installed on the 1098. mmm, chrome.

sorry, guess I should've done a search first

 

[Spridget64SC]

All 948 and 1098 oil pans will interchange. Whether 1.75" or later 2.00" 1098 mains. 948/1098 and 1275 will not interchange. The reason is the rear main bearing cap. 1275's are just a bit wider. Compare the cork gasket inserts of the 948/1098 and 1275. 1275 has two different lengths. 948/1098 has two the same length.

Now, that being said, there are some differences between the 948 and 1098 oil pans. They have to do with the difference in the crankshaft stroke and the attendant arc that the rod follows. The 1098 oil pan is "thinner" along the pan rails. If you are using an aftermarket rod that is "Straigh-cut" for cap removal across the cap rather than diagonal, you have to use the 1098 oil pan on a 1098 or the rods will tap the oil pan near the distributor side rail. That is where all the shaping is made in the block and the pan. Occasionally, when using a Carillo rod, one will also find interferences on the manifold side rail. Not much, but sometimes one has to grind away the block in a few places.

Put a 1098 oil pan beside a 948 and one can see the difference in the thickness/widths of the raised boss front to rear on the oil pan rails. It is subtile, but it is distinctive in a few places.

Got some pictures of the two pans side by side, but can't figure out the upload routine.

HTH, Mike Miller