Adding leaves to front spring.

[Mike Britton]

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When this car was a race car, it had a small block, and the front end worked fine.
Since, I have added a big block ,which means an extra 75-100#. I know, the shocks need to be stood up, something I plan to do when the chassis side of the build comes.
My question is, can I add extra leaves to this spring? Typical T-bucket front springs are 26"- 4 leaf springs. Although the front end feels fine sitting in my garage, I believe it would benefit from at least two more leaves. Typical "A" springs have six,or seven leaves.
Could I simply buy another 26" spring, and take some leaves from it to add to mine? Let's say I add the top two leaves, can they be the same length? Or do I have to shorten each leaf to be less than the one below it? If four leaves prove to be insufficent, what will happen? Will the axle bottom out against the shackles? Would it be prudent to incorporate a bump stop on the bottom of the perch?
Thanks, Mike

 

[RPM]

Yes you can add leaves to that spring. But I have to ask, what is it you are trying to do, raise the chassis height? Adding leaves might raise the chassis, but it will definitely make for a harsher ride. The bat wings are too close together, or the pivots are too long, I can't really tell from the pic. The shackles when the spring is loaded should be about 45 degrees.

 

[marcus]

Mike;

If you add the 2 top leaves to your spring pack, they will add minimal "springing", but will add height to the pack, & the front of your car.

Adding 2 of the bottom leaves, will increase the weight carrying ability. Yes the leaves "should" be stacked in a pyramid fashion, w/each leaf slightly shorter than the one below it. You can just stack 2 leaves of the same thickness, but I think they tend to act as one very thick leaf. = one miserable ride.

I would start out with cutting another of the longest leaf so its' length is halfway in between the longest leaf & the one ending at the red clamp. Not counting the mainleaf w/spring eyes as the longest leaf here. Should help w/the extra weight. Although, you may find that you don't need it.

Marcus...

 

[Youngster]

I wouldn't do anything to the spring at this point. See how the current spring works first. Remember the shorter the spring the stiffer it will be. I have seen a spring like that work very well in a bucket with a BBC. My 2 cents.

Ron

 

[Mike Britton]

Ron, I've been wondering if I was trying to fix something that "ain't broke". I've looked at many T-buckets in this area with both big chevies and big fords, and all but one of them had a typical bucket spring like mine.
When this car was in it's prime, before it came to live with me, it was moved by a 400 in. sbc on methanol, with Hilborn injectors. Best pass, supposedly was a 9.35 at 145. Also, the wheelie bars showed evidence of wheelstands!
Then it had a spring behind, looked like maybe a CCR axle. I replaced that axle with a Speedway spring over to get the front up out of the weeds.
I still have to raise the rear coil-overs about 2", to get the drivetrain down out of the cockpit, so I can use the addition of a couple of the short leaves to raise the front to get the stance right.
The original builder had about 5" of aluminum spacers in the front perch trying to get better forward bite. The engine I had in there only made about 350 H.P., so I took them out, and the front end was much happier. The car felt pretty good with that setup, the only difference now being the 75 or so pounds of the big fella.
I intend to replace the drum fronts with discs, kinda like "what was I thinking!!??!!" so there will some difference in weight there.

BTW, RPM, it's hard to tell, with everything being black, but the shackles really are at about 45deg.!
I'm 6' and 240, and when I jump up and down on the perch, the frontend moves as it should. I was just concerned about what happens out on the street. Thanks, guys, I'll wait for the "around the block" shake down runs, worst case is a new axle with the larger 30" spring.