1971 chevelle ss 402?...

[shadowgray396]

First off welcome to the site.

As far as I know only the 300hp was offered in 71. What you need is the engine identification code which consists of the engine assembly plant, the engine assembly date, and 3 letter suffix indicating the cubic inch displacement, the horsepower rating, and generally, what type of transmission was to be installed with the engine. The suffix codes on the motor would be one of these - CLA, CLB, CLL, CLP, CLS, CAJ, CLK, 71 was the start of lowering the horsepower on the engines.

The big block and small brackets are specific to either BBC or SBC. Also keep in mind short water pump and long water pump accessory brackets are not interchangeable. I believe the same is true on some of the pulleys but not total sure on that. Since you are doing a different motor I would go with a different distributor that you could update but look stock.

Possibly be able to use the starter and flexplate off the small block and use it on the big block also if you are using the same transmission..