who makes larger stroke cranks and where can i get thme i know callies makes a 3.875 any help?

 

Any SBC crank for a 2-piece real seal will work. Callies, Lunati, Eagle (Chinese forging), etc. make 1-piece rear seal 3.875" cranks. there must be others as well. You can use a crank with a 2-piece rear seal with an adapter.

10051118 Crankshaft Seal Adapter
A leak-resistant one-piece rear main bearing seal was introduced on production small-block V8 and V6/90º Chevrolet engines in 1986. Crankshafts in these engines were also redesigned to accommodate the new one-piece seal design. This adapter kit allows you to install an early-style crankshaft designed for a two-piece seal in a block which is machined for a one-piece rear seal. This seal adapter can also be used when installing a heavy-duty crankshaft in a cast iron Bow Tie small-block or Bow Tie V6/90º block machined for a one-piece seal.

Rich

 

I have seen 4 and 4.125 with the aqdapter

 

Eagle 3.875 and 4" 1pc seal

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