Thread: Four Link Specifics Required

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Hmm, a 289 in a Cortina should be very interesting.!!!! The parallel 4 bars work great, another option to consider would be a triangulated 4 bar. Your plan for the parallel 4 bar would work fine!

For the street, the coilovers work best if angled in from the bottom to the top at an angle between 25 to 28 degrees. Some manufacturer's suggest their coilovers mount at 30 degrees.... Mounting the coilovers vertically leads to a harsh ride and is best left to the drag cars... If it were my choice, I'd go with the new crossmember and the coilovers angled in.

A panhard bar is the easiest solution to control lateral movement. The mounting height on the rear end housing can also be raised and moved forward so that the panhard bar is forward of the coilovers and above the housing. Also, the nearer you can have the panhard bar to parallel with the ground at ride height, the better off you are.

I would say you are on track, if you have any other questions, ask away!!!

Ditto. You can buy your four link bars in custom made lengths, and even get the bracketry that joins them to the frame. We are right in the middle of installing a fourbar setup in my kid's '29 right now. We are using quarter eliptic springs, but coil overs would be even easier. A panhard bar is going to be used also . We have to still make and install tube cross members, one of which will support the shocks.

Here are a couple of pictures of our installation that might help somewhat. One source for components is Auto Weld in Pennsylvania, among many others.

Don

You may not have to cut your floor if you run both upper and lower bars below the center of the axle.

Take note of the upper bar placement as pertains to axle center:
http://i49.photobucket.com/albums/f2...tarRRTsize.jpg


Here's an undercar pic that just barely shows the axle bracket.
http://i49.photobucket.com/albums/f2...2BrakeLine.jpg

Said bracket is a Chris Alston ladder bar axle bracket with the top front cut off at an angle and a new hole drilled a bit lower.

Bars are home-made, 1" x .120 wall DOM tubing with helicoil threads.
1" x .156 wall directly threaded may have been better, but the .120 wall tubing is working fine.
The roadster has a very torquey (about 530# torque) 462" Buick engine.

The four bars are parallel in both the side view and the top view.
There is a long panhard bar in front of the rear axle.

Recommendations I've read for using a 4 bar on the street say to run them parallel horizontally and vertically.
This is not drag racing practice, but it works quite well on the street.

The car handles well, especially so on twisting mountain roads - much to the dismay of a few sporty type cars - and has good highway and in-town manners.

An experienced at drag racing friend noted that the car squatted a touch on take off.
That's normally an indication of less than optimum traction when accelerating, but in actual use the car launches fairly well.
Running 8" tread width street tires at the drag strip the roadster can keep up on the launch and pull some of the dedicated drag racing door slammers with big slicks in 2nd gear.

I have another roadster under construction, a 31 A on a 32 frame.
This one has a Chris Alston ChassisWorks 4 link under it and has quite a bit of adjustability so I can run the links parallel or set up for a better "Instant Center" for drag racing use.
The bars are similar height-wise to the ones in your first photo, but I didn't have to cut the floorboard.

Pics of that if you wish.