With cost being part of the object, what are the pros and cons of each kind of rear suspension for a strip-only drag car? I'm planning the chassis fabrication for the Slampage and I'm considering each of these types.

I like the leaf spring for its simplicity. Coupled with Lou's discovery of the lightweight fiberglass leaf, I think a very lightweight suspension could be produced. I'm sure it would need some kind of traction-control bars to work in this application.

I like the ladder bar for its adjustability and the elimination of axle wrap. Coilovers...diagonal link...

I like the four-link for its adjustability over the ladder bar. It seems like it would be harder to get it set up right. Any input?

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It's a Slant thing. Even I don't understand.

1974 Duster, EFI /6 soon to be turbo...

Get that Monkay! Get that nasty thing!!

Personally, I'd go with ladder bars. You will end up with a car that will repeat better than a leaf spring car. It won't be as adjustable as a 4 link, but it won't cost near as much either.

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Official Cookie and Mater Tormentor.

me to

Will

Oddly, the 4-link stuff from Competition Engineering comes in about $100 cheaper than the ladder bar stuff. I was really set on the ladder bars too until I noticed that.

_________________
It's a Slant thing. Even I don't understand.

1974 Duster, EFI /6 soon to be turbo...

Get that Monkay! Get that nasty thing!!

Are you sure that includes the rod ends, brackets and track locator? There's a lot more parts in a 4 link than there is ladder bars. Ladder bar is much easier to install too.

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Official Cookie and Mater Tormentor.

Yeah, you're right. Does not include rod ends. They are pretty expensive too.

_________________
It's a Slant thing. Even I don't understand.

1974 Duster, EFI /6 soon to be turbo...

Get that Monkay! Get that nasty thing!!

A lot depends if you want to keep the stock frame rails.
Leaf spring they can stay.
4link they have to go.
Ladder bar they can stay, but a lot of fabrication has to be done. The coil overs are so tall they can't fit under the stock floor in the upper shock mount area. That area has to be cut out and mounts built up inside the car. Most chassis builders say it's better to put in new frame rails.
I've had 1 ladder bar and 3 4link cars over the years.
4link: there may be 100 or more different link combinations, 25 may be useable, it's easier to change when making adjustments, preload is easy to set, if a rod end breaks it's safer, takes less pinion down angle, usually has less chassis bind no matter which housing locater is used, I've had all 3 types of locaters on my 4link cars, diagonal, wishbone and watts linkage, the wishbone and watts allow for zero bind, a good set up but not needed on all but the fastest slants.
Ladder bar: only 2-5 front rod end settings depending on crossmember bracket holes, hard to get lost making adjustments, harder to make changes when front hiem end saftety straps in the way (straps may save you and car if joint breaks), non-adjustable bars are hard to make preload settings, most adjustable bars put stress on the bar when setting preload, I like the looks of the pivioting adjustable bar from Competion Engineering, set preload with bar stress with their set up, they are probably easier to install than 4link and take up less interior room, you can run fast on ladder bars, I think Charles Myers has them on his 9.93 car!
Leaf springs: How easy and cheap can it be, can be adjusted by moving clamps on rear half, can be upgraded easy to a CalTrac/monoleaf set up which has more adjustable features such as 2 front mount holes, preload capable, force of intial hit by use of bracket gaps, I've never used Caltracs but think I will try them when I get my car that far along.

Cecil

Thanks for the input Cecil. The chassis will be totally fabricated. Only the outer sheet metal and the cab/firewall/door hinges will remain.

The Rampage is a unibody type design, so it will need a complete chassis once it gets cut up.

Looks like ladder bars are getting the nod. I'm considering the adjustable ones from CE, as you mentioned.

_________________
It's a Slant thing. Even I don't understand.

1974 Duster, EFI /6 soon to be turbo...

Get that Monkay! Get that nasty thing!!

GP - IMHO if the chassis is going to be completely fabricated it would be money well spent to go with the 4-link. Lots more versatility in a 4-link than any other option.

All the points Cecil made are true. Not much to add but if you are going to the trouble to fabricate a complete chassis then it might be wise to consider a 4-link. I have seen too many ladder bar systems that one adjustment either way is waaayy too much and the current setting is not quite right either. Just my .02 worth.


Tom

AAAUUUGGGGHHH!!!

Thanks for the input...I'll have to look at the dollars and...sense.

_________________
It's a Slant thing. Even I don't understand.

1974 Duster, EFI /6 soon to be turbo...

Get that Monkay! Get that nasty thing!!

Personally, I think installing a ladder bar setup is a piece of cake compared to a 4-link. I have helped install 3 ladder bar set-ups and one 4-link, and the ladder bar is considerably quicker to do.

4-link is a PITA too if you don't happen to have enough room for the right length on the top bars, but you should be OK there.

_________________
Official Cookie and Mater Tormentor.

What type of frame are you "fabricating"? A complete tube chassis???

If so there should be plenty of room in the bed of a rampage for the 4-link. Dennis is right, if you are doing this yourself then the ladder bars are the way to go. Much easier to install.

GP - Are you doing the work yourself or having a chassis shop do it for you? What ET range are you shooting for in the 1/4 10's, 9's...or maybe 8's?

Tom

One other set up that is not seen on newer drag suspensions is the 3link. A bud of mine has one on his Vega. Uses a wishbone for the axle locator. It was common on Pro Stock Chevys in the 70s. Grumpy and WJ ran it. Theoretically, it's the ultimate suspension. I wouldn't want to break a rod end with this set up.

Cecil

It will be a square tube chassis. My starting point will be an A-body K-member. I plan to use the Comp engineering rear frame sections for either the ladder bar or 4-link setup, along with the appropriate crossmembers. I'm doing it myself.

It will have a complete rollcage to stiffen the chassis (and protect my noggin).

ET range - I don't know yet. I want to build it as light and simple and strong as I can, and start out with perhaps not the ultimate expression of a slant 6 engine. Then as time goes on, maybe one can be pieced together...

_________________
It's a Slant thing. Even I don't understand.

1974 Duster, EFI /6 soon to be turbo...

Get that Monkay! Get that nasty thing!!

Buying the complete rear section will greatly simply things.

Good Luck.


Tom