SBC oil dipstick tube size

[br80z]

SBC oil dipstick tube size
Did GM use different size holes on the Chevy small blocks over the years?

I have a 350 block I think is between a 1972-1974 block number k06 08 ckb wit the dipstick on the driver side, and none of aftermarket dipsticks I have tried fit right. The hole in the block measures .418" and the aftermarket dipstick tubes measures from .442"-.445"

Does anyone have part number to a dipstick and tube that will fit this block, with headers?

Or maybe I should just drill out the hole in the block to match the aftermarket tubes, while I have the engine out of the car?

Suggestions?

 

[Twisted_Metal]

Yes... They used different sizes and some were driver's side and some were passenger side.
Later crate engines had dipstick holes on both sides (different sizes) and came with plugs to block the unused one.

There was even a goofy one on some 305's which went through the oil pan instead of the block.

Unfortunately... Most places which sell dipsticks don't list the tube diameter so I don't know how you would find the one you're looking for.

Drilling the block might be the easiest remedy since it's less than a 1/32" you would need to remove.
It's a friction fit so you would want the hole a few thousandths of an inch smaller then the outside tube diameter to hold it tight.

You might also be able to taper the edge of the new dipstick tube to get it started as they will compress a bit when driven into place.

 

[muscl car]

When I installed my Mr Gasket dipstick tube in my new Dart sbc block I just used a drift punch and it went in easily and fits tight

 

[biker]

If it really is super tight, think ahead a bit as to when you install it. If you install it while it's out of the car and then find out that u can't fit the header on that side once you set the engine in the car, it's a big wrestling match to get the tube out again.

 

[Twisted_Metal]

^ Good Point!
I waited until the engine and headers were in the car before I installed the dipstick.
(Even though the shorty headers were bolted tight to the heads when the engine was installed.)