1972 Small block Vs Big block 9 leaf rear spring

[72ray]

Is there any difference between the two?

 

[Riley P]

The only difference I have heard about the springs is I believe all the early C3's used the 9 leaf rear spring where if it was optioned with the F41 suspension, then it got the 7 leaf rear spring and heavier coils and stabilizer bar up front.

 

[72ray]

Any thoughts about this set up?

 

[gdh]

Same as what I am running In the rear (Bilsteins & 7 leaf). Front: 550 lb springs, Bilsteins, spreader bar. Inside: rollbar. Wheels: 17” TT2 with Nittos & upgraded larger brakes. I did each mod separately to feel the difference each change would make. The spreader bar which is the most inexpensive had the biggest single difference as it keeps the shock towers from flexing. Next will likely replace the original steering box with a new Borgeson unit.

 

[CorvetteRon]

Same as what I am running In the rear (Bilsteins & 7 leaf). Front: 550 lb springs, Bilsteins, spreader bar. Inside: rollbar. Wheels: 17” TT2 with Nittos & upgraded larger brakes. I did each mod separately to feel the difference each change would make. The spreader bar which is the most inexpensive had the biggest single difference as it keeps the shock towers from flexing. Next will likely replace the original steering box with a new Borgeson unit.

Wow, when I was playing with the suspension forty years ago all my choices were "these were for Daytona'" and "these were for Sebring" etc. I settled on what I liked but kept several rear sway-bars as I thought they made the biggest difference, and I even change them when I get new tires to match the new tires different handling characteristics.

 

[V8!]

When I had my C3 I had a composite leaf and was great, was a big block car. Miss that one.....

 

[72ray]

So today’s learning point is that BB rear springs have larger gauge mounting bolts than SBs and therefore the mounting plate has large holes to accommodate but with the same ‘footprint’.

 

[72ray]

 

[72ray]

The BB bolt here is only longer as the spring has two extra leafs added to it but the difference in thickness is remarkable

 

[72ray]

It’s in!
Big block, 9 leaf spring, with an additional two leafs manufactured in it for a project with a heavier rear end by a guy I found on line. Other than the need for longer G8 bolts to secure it to the diff housing, it went in beautifully and I’m happy with the results. Stiff but not jarring, clears the speed humps without looking too jacked up.

 

[72ray]