VFR750,
Yes the GT3 rod bearings are 100% interchangeable on the 3.0L SC rods. They snap right in and work perfectly. Same dimensions as stock 3.0L SC bearings
Regarding the Clevite 77 bearings, don't confuse the "Chevy" application that has been mentioned here on the forums in years past. That is often mentioned in reference to grinding the crank & rods to accept a Chevy NASCAR (actually originates back to a Buick application) bearing.
Two Inch NASCAR Bearings That trick to use NASCAR bearings in the 2.7 rods is not the Clevite 77 bearing that Auto Assoc. is providing. Note that 2.7 rod bearings are not the same dimensions as 3.2/3.3/3.6 (not GT3) rod bearings.
Since I brought up Glyco vs. original Porsche-boxed quality, I figured i'd take some pictures to show that it's not just a myth that Porsche selects their bearings and measures them vs. just taking whatever Glyco produces.
Here's a picture of a STD main bearing from the Glyco aftermarket box, the box itself and then an original Porsche-boxed bearing on top of its box. First picture is not real pretty but it's really not that bad. It's some discoloration of the anti-corrosion silvery stuff. Still, not all that confidence inspiring is it? Notice how the bearing on top of the Porsche box has three marks around it on each side of the bearing where they measured it.
Next here's some aftermarket Glyco rod bearings for a 3.0L. The bearing fit/finish actually looks quite nice as you'd expect. Notice the shiny backing and the 03-13 date code
Here's the GT3 bearing from Porsche with its apparent dry moly coating and measuring marks on it. Also notice in the second picture the blackish plating on the back and the Porsche part number (not present on the aftermarket 3.0L bearing or aftermarket main bearing)
Lastly, i'm not saying Porsche-boxed bearings are perfect. Look at the ugly #1 main/thrust bearings I received from Porsche earlier this year.
