Aftermarket Conrod clearance

[modnrod]

Gday all.

I haven't asked a dumb question for a while, so here goes! 

There a plenty of aftermarket conrods available, commonly in both Chev journal versions and normal VW journal. The Chev journal rods have a smaller I.D. on the big end of course, but what about the diameter of the big end outer circumference?
Are both VW and Chev rods the same outer O.D., just machined for a different bearing size (which is what I've heard once or twice), or are the Chev journal rods also smaller outer O.D.?

Also, when using the common aftermarket H-beams in a stroker build, does anyone know exactly how much extra clearance to the case there is over the stock VW I-beam rod? 0.5mm? 1.0mm? 1.5mm?

Thanks in advance.

[richie]

Chevy are smaller OD as well, Scat big bolt[3/8] VW journal is 3.330 approx. across the widest point opposite bolt head, same rod but chevy journal is 3.230 approx. stock vw in the same place[ opposite nut] measures 3.250.
The small bolt version [5/16] is about 3.240 VW journal[scat rod]  and 3.180 chevy journal carillo


cheers Richie

[modnrod]

Thanks Ritchie.
Just for clarification, the 3.180 Chev journal Carillo is a H-beam?
Do you know if CB Super rods (or AA perhaps?) are likely to be similar at all?

That's actually more than I thought, .070" (3.250 - 3.180) from Stock to small journal is a fair bit.

[richie]

Yes carillo is a H beam, I looked at some CB rods I have but a previous owner ground the shit out of them for some reason so there is not enough material left there to get a comparission

cheers Richie

[modnrod]

Much appreciated, thank you.

[Taylor]

Pauter 2" light rod with 5/16 bolt is I beam and 3.125". 

[modnrod]

 
Cool! More clearance means more oomph.

[Fiatdude]

Carrillo come in both H and A beam -- and each type have several levels of quality (cost LOL) I've got a set of H beams in my engine -- the H beams are the strongest, but the A beams are the lightest and could be used in high RPM NA (light load) applications

[modnrod]

For my little motor I actually have none of those things.
That is, no revs and no horsepower! 

I would like a narrow rod with Chev journals and Porsche length, there is CB Super and I think AA maybe?
It will just save me modding a local rod, off the shelf (without huge freight bills for it) is just easier, as long as the quality is OEM.

Some good info on here though, thanks guys.

[richie]

Scat sell a 5.325 chevy journal h beam as well

cheers Richie

[modnrod]

Old thread, but a quick addition to the info here for everyone else.

I just bought a set of AA Chev journal 3/8" bolt I-beams.

Measured clearances.
Stock VW rods.......


AA I-beams........