Hi all,

I bought a 71 convertible with a big block.  No matching numbers.  Could someone tell me about the leaf springs in the rear.  Should big blocks have 7?   Also, can I tell by the front thickness of the sway bar?   Are there other items that tell a big block from a sm block.

Thanks

Ron

The springs in the front are stronger, the half shaft u joints are different & I think the radiator was different. You'll get a lot of responce on this

Alan

sounds like you are woundering if the car when built was built with a Big Block or a small block . There were "regular" suspensions and Heavy Duty suspensions - both available for small and Big blocks decoding the production codes should ltell you if it was born big or small

Big  Al

There was no paperwork with car.   I am striping it now,  pulled out everything, carpet, seats, etc.   Pulled fuel tank, have everything out.  Saw on top of tank where glue was.  Previous owner didn't know either, he bought it used also. 

Thanks,  I'll keep checking the history.   someone has to know something.  If not, it doesn't matter.  When I'm done, it'll be fine.  It's a big block now.  

I like yer' ride, Ron......SWEET!

Keep us posted on your history hunt!

There is a difference in the fuel line from the frame to the pump between bblks and smblks. That's usually one of the small things that most people don't change when swapping small to big. The redline on the tachs are different, too.(I think?) The exhaust pipes were "mashed" a little flatter where they go under the diff. on bblks.(but so were the HP smlblks)
Radiator, fan size larger, but easily changed. The list goes on.....

Look for a metal radiator overflow tank for the BB.  Just one more thing to add to the list.

Your drive shaft caps will be a cast piece, not just a strap. A lot of people miss this one.Sway bar size Was bigger for a big block, I'm pretty sure, but also an indicator of F-41 suspension. Number of leafs is 7 for an F-41, 9 for stock. Does it have the rear sway bar?

Red line was higher on H.P. big blocks.

Your car looks pretty awesome! If you don't have any records for the car, you won't be able to prove or disprove what it was new. Enjoy what you have and have fun with folks slobbering over it!!!!!!!!!