What's to choose

[Malice]

Looking at an art morrison chassis for a 67 camaro. i saw you can choose between a triangulated four-bar or three-link rear suspension. Can someone tell me the difference between the two and what to choose? What are the features and benefits of each?

[Ron Sutton]

Assuming both types of rear suspensions are set-up correctly, similar rod ends, spaced away from brackets properly with high misalignment bushings & clocked correctly ... A 3-link suspension will allow the rear axle to articulate more (roll angle in relation to frame) than a 4-link.

They both will bind at some point of articulation. A 4-link will bind at a much lower degree of angle difference than a 3-link, all things being equal.

"Parallel 4-links" & 3-links require a device to keep the rear end centered in the chassis, like a panhard bar or watts link. A triangulated 4-link does not require this, as the bars running at an angle keep the rear end in the location you put it. There are pros & cons both ways.

A triangulated 4-link is simpler. It could be argued it will handle more torque under hard launches, but if you were going to drag race it with slicks, you want want a Parallel 4-link, not a triangulated 4-link.

3-links can handle drag racing up to a point, but it wouldn't be my choice if the car was planned for 800+ hp, high rpm, clutch dropping, slick running, wheelie pulling launches ... as there are only 2 rod ends "pulling" to lift the whole car. :ohsnap:

A suspension with a panhard bar or watts linkage ... "can" allow for easy roll center changes, if the brackets allow for adjustment. :D (Most kits sold do not have adjustment capabilities) :headscratch:

So, for the best road racing, track car, or AutoX car, the 3-link has the advantage. For drag racing, the advantage goes to the Parallel 4-link.

For a "cruiser/driver" that will only occasionally see the track, the triangulated 4-link may be fine. Not better, just simpler.

Make sense now?

[Greg from Aus]

Ron you really have a great knack at explaining things, I went for a combination of the two, from Morrison's, a 5 bar set up, that can be switched between 4 link and 3 link.

[Ron Sutton]

Thanks. One of my friends said, Ron is a race car designer that did not go to engineering school, so he speaks "guy".

I think it was a compliment, but I'm not 100% sure.

Greg, I saw your set-up & love it. With 6 bolts, you can go from optimum drag set up to optimum cornering setup.

[Malice]

I think that's decides it. I think I'm going a 3-link. Thanks for the help. That explained it very well.

[Ron Sutton]

Cool,

Post photos of your build or changes to keep us in the loop.

[Malice]

This is currently my build right now.

[Flash68]

Thanks. One of my friends said, Ron is a race car designer that did not go to engineering school, so he speaks "guy".

I think it was a compliment, but I'm not 100% sure.



Ron, love that quote!

And thanks for your continued sharing of knowledge on this forum. Cheers

[Ron Sutton]

Malice,

That is a sweet Camaro you're starting with. :thumbsup:

Start a project build thread once you get going. We all enjoy seeing what other people are doing too.

Take care.

[Ron Sutton]

Ron, love that quote!

And thanks for your continued sharing of knowledge on this forum. Cheers

Thanks. I like to help, when it's something I'm knowledgeable & experienced in, which is usually performance & fabrication areas.

I also like to learn from the guys on this site, in areas my knowledge & experience are weak, which is usually aesthetics & style stuff.