Im trying to find out the rod big end ID and the bearing size and thikness and also the crank diameter for the rod end. I bought 2 workshop manuals and both are very limited in what they tell you.

The reason for this question is that i believe i cant make the rods and pistons from a vr38dett fit which would give the 6g75 a bullet proof bottom end appart from spliting the block from harmonic strain. Any help would be great Thanks

3.5 rods and 3.8 rods are interchangable

3.5 TH rods which have been shotpeened are bulletproof. There are a few FI magnas that have run shotpeened TH rods, and they havent had any issues.

Look on the 3si forums and you'll see when those guys try to get their 3.8 blocks to something like 800awhp, the cranks flex and snap.

How much power you expecting to make and what drivetrain (awd/fwd?)

Its not so much the rod itself its the tinny pin size to the piston, the 3.8 runs a 22mm pin where the r35 gtr runs 23.5 mm pins also there are a huge range of after market rods and pistons for the vr38dett and i know the standard bottom of the r35 holds up to huge power as the time attack car we built is making 830awhp.

my goal is 650 too 700hp+ on e85 in rwd to stop the flex im working with a friend who will be machineing me a billet main girdle to try strenghten the crank.

Think there is an old thread that had a lot of these measurements in it. Compared bores and bearings etc between 3.5 & 3.8

I did a search but only found 1 it had things like lift and duration valve sizes and bore side