We are thinking about swapping a 330 for a toro 425 in a 67 cutlass and was wondering what opinions you guys had on the 425 engines? Would this swap be the same as going to a 400 or a 455? Thanks

 

I vote do it. A short stroke 425 will knock your socks off in stock form over the 330. Do a search of our late Chis Witt's (Octania) take on the 425's.

 

A 425 is a bit more expensive to rebuild than a 455 due to parts availability and differences from its other BB counterparts. A 455 will have more torque over the 425. The earlier (prior to 68) 400's are great engines, the later not so. Its a matter of choice, I'd go with the 455. They all install basically the same.

 

I think the only price difference between building a 425 vs a Toro 455 would be the pistons.

Sounds as if the Op is just doing an engine swap, though.

Yes.

There is one minor detail - the 425 uses the same flex plate as the 330 whereas a 455 would use a new style flex plate used on the 350/307/260.

 

Do it.

... But keep the 330 - they're nice engines, too.

- Eric

 

I believe the lifters are different also and very expensive.

 

I thought the Toro engines used .842 diameter lifters? It's hard for me to remember the different variations for the different years and applications, though.

Even if they were the .921" lifters they aren't that much more expensive.

 

The Toro 425 had the large lifters in 66 and 67. The non toro engines were the smaller ones. The 66 and 67 Toro 425 had 39 deg lifter angle. The 65 and 66 425 had 45 deg lifter angle. In 67 the non Toro 425 could be either lifter angle.