bb vs sb rear end, how to tell c2

[Tony DiGiorgio]

Is ther any physical way to tell a bb rear end from a small block other than the code stamped on housing? I cant find code and unit still under car very rusty and greasy?
Thanks in advance
Tony

[mike mccagh]

Re: bb vs sb rear end, how to tell c2

small block U-joint trunions held in place with U bolt, big blocks with pair of bolts and a cap. bb have sway bar, small blocks don't.mike

[Joe L.]

Re: bb vs sb rear end, how to tell c2

Tony------

The code is the only "positive" means of ID. It's really a moot point, though, since the ONLY difference between small block and big block differentials is the stub axle u-bolt retention. Plus, after about 1970, the big block style stub axles began to be used on some small blocks. Except for "codes/dates", rear ratios and stub axle type, all 1967-77 Corvette differential units were the same. 1978-79 were the same, too, except that the cover changed for these years.

[Ken B.]

Re: bb vs sb rear end, how to tell c2

Tony, I think you may find (on C2's) that the fuel line ("pipe") from tank to front of frame -engine compartment on the BB is approx. 3/8" OD ----I seem to remember the SB versions had a a smaller fuel pipe---maybe 1/4"OD pipe. I hope I'm not misleading you as I've been away from the heartbeat of these cars for a while. Best that you double check as I am totally working from recall not from research data.

ken barrington

[John H.]

Re: bb vs sb rear end, how to tell c2

Ken -

All Corvettes from '57-up had 3/8" main fuel lines.

[Ken B.]

Re: bb vs sb rear end, how to tell c2

John,

Thanks for the correction re: fuel line pipe size for C-2 corvettes. I do appreciate you much.

Ken

[Wayne M.]

LENGTH matters

Ken, The BB fuel line is about 4.5 inches longer (ends more forward). Check from the fuel line clip at the frame (near the idler arm bracket); should be approx. 9.5 inches to end of steel on the boat anchors, and approx. 5" on the mouse variety.

[Ken B.]

Re: LENGTH matters

Wayne, I "preciate" the update concerning the fuel line difference in BB /SB C-2's...You have save me some time researching as I remember something was different regarding the fuel line..I will remember " Length does matter " , the next time the question is asked.

Have a Heathy and Happy New Year, Regards, Ken