Rod bearings- red and blue markings

[Peteinjp]

Just curious- though I think I know the answer always good to check. Opened my single set of Porsche rod bearings (standard) to find one with red and one with blue markings. Measuring the difference in thickness the blue ones were .01mm or .0035” difference. Are these high tolerance groupings?

When I get the other sets- presuming that these are high tolerance groupings- should I match them up in any particular way?

[Flat6pac]

I recall the GT3 crank use color code on the rod bearings to signify tolerances needed for proper assembly.
Bruce

[Peteinjp]

My bet is that in the factory they actually match the higher tolerances on the RS and other engines- maybe all of them so you have a small, med and large standard bearing to match small medium and large standard journals. But that is just a guess.


It just threw me off at first because I seem to recall my old Bmw 2002 using similar markings to differentiate between standard and over size bearings.

Pete

[targa72e]

GT3 cranks were color coded on each rod journal and bearings were tolerance matched. Pic below shows yellow and red marked journals on gt3 crank.




john

[Peteinjp]

Hmm- that's cool I suppose I could try to match them up. Will the rod and main Gt3 bearings fit the 964 crank? It seems strange to me that the 964 part number can't specify the tolerance group.

Pete

[targa72e]

mains are the same as gt3, the rods are different. gt3 rods are same size as SC 3.0L. 964 uses same rods as 3.2/3.3 engines.

john

[Peteinjp]

Too bad- I already have the mains bearings. Rods- considering clevite 77


Pete

[Fever]

Gt3 cranks are color matched to the bearings, great way to do a perfect match.,
Jay.