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.

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

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]

Originally Posted by 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.

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.

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

Take care.

[Ron Sutton]

Originally Posted by Flash68

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.