Will a porsche 901 fit with no mods to a stock type 1 engine?

[GS guy]

ydeardorff,
Just remove one of the output flanges from each trans and compare. I did this last night with my spare 901/930 output stubs and 914 stubs - near exact match except for the CV flange - so they definitely directly interchange. One thing that surprised me was the bolt that holds the stub into the trans. It take a fairly large 3/4" size socket, but the bolt itself is fairly small and not super hard to remove out of the trans. I made a simple "wrench" that could be bolted to the CV flange with a couple of bolts to hold it while loosening the bolt.

I don't think there are any strength issues with the 4-bolt flanges, FWIW. The two large dowel pins that locate the CV probably provide more rotational/shear strength and (2) 8mm bolts would.

Jeff