Chevrolet V8 Water Pumps

All Corvettes up to and including 1968 used what's commonly referred to as a "short pump" and from 1969 to 1972, a "long pump."  Both the small block and the big block used a short or long pump.

Either the short or long pump may be used with its respective engine as long as you also use the corresponding brackets and pulleys.

The general rule of thumb is if you can put your fingers between the back of the water pump and the timing cover, it's a long pump; if you can't, it's a short pump.  The photos show the length of each pump.

While there is room to put a long pump and its brackets and pulleys into an originally short pump car, you must be very mindful of the fan-to-radiator clearance.

I've also discovered that while most factory big block pumps use a 2-inch lower hose outlet, some aftermarket big block pumps (such as the TuffStuff unit - also sold by Summit Racing) use a 1.75-inch outlet.  There may be others, but this one I'm familiar with.  Not saying this is good or bad, just something to be aware of.

Reverse rotation pumps are used on many serpentine belt systems and cannot be used in place of normal rotation pumps.

Small block short pump

Small block long pump

Big block short pump

Big block long pump
(Some specs show 7.25")