Burtz cam bearings hole

[gdmn852]

Hello pushed out cam bearing and drilled a 1/16 hole, seems a little small the rest are are around 1/4 ,also to align with oil passage it will be located around a 45 angle. Some pictures

 

[Terry Burtz Calif]

The hole in cam bushings 1 and 4 needs to be small if you are using an original 5-bearing camshaft because the oil distribution groove goes completely across the camshaft journal and vents to the crankcase. Whenever the groove aligns with the feed hole, there is a drop in oil pressure and the gears in a mechanical oil pressure gauge will wear. If you are using our new 5-bearing camshaft, the oil distribution grooves do not extend to the ends of the journals, and the hole can be larger. The small feed hole works with original 5-bearing camshafts and the new camshaft.

 

[gdmn852]

Hello,thank you for replying, I am using the Burtz cam , what size hole do you recommend? Thanks again.

 

[JayJay]

Hello,thank you for replying, I am using the Burtz cam , what size hole do you recommend? Thanks again.

gdmn - Builder's Guide says 1/16". I am using a Burtz cam as well, I believe I drilled either 3/32" or 1/8" just to use a stiffer bit with less chance of breaking it. As Terry points out, with his new cam the distribution groove in the journal does not extend completely across the journal, so the bearing hole size is not what limits flow through that bearing.

 

[gdmn852]

Thanks for the replys one more thing, which oil slot should it be aligned to? Angle or one that will get plugged ?

 

[Terry Burtz Calif]

By slot, I think you are refering to hole. Align the hole in the bushing to the upper hole in the cylinder block that connnects to the main oil gallley. Do not align it to the lower hole. The lower hole is only there because it was needed to drilll the upper hole, and it gets plugged with the bushing.

 

[gdmn852]

Have them in ! Thanks everyone for your help!