[DNCII]

Hey fellas!

I have been searching this forum, CC, HAMB and just plain Googling But i can't get the answers that I'm looking for. I'm hoping that someone can help (Billy???????).

The car is a '32 Ford Tudor Sedan. The rear of the frame has been "Z'd about 9 inches to lower the back and allow me to use some 30" cheater slicks. I will be running a blown big block; so figure 800-900 HP/TQ. This will be primarily a street car, not a show car, but an actual driver. It may see a strip a few times.

I have designed a parallel 4 link with 18" bars that i can run in a parallel fashion for the street OR move them around for drag racing, better AntiSquat, etc. I just got the body (Fiberglass, Deuce Customs...AWESOME) and it has a main crossmember running right where I had intended to put my 4-link brackets. So my first option right is to move the chassis crossmember back and use ~16" bars. Will these be too short?

My next option is to see if i can convert my current 4-link design into a 3-link. The car is so low, it will have a rear tunnel inside anyway, so why not take advantage of it? My idea would be to "cut" the brackets in half so that all of the bottom holes are available for the bottom bars and move the top brackets to the center (or a bit to the right as space permits) and still run an 18" top bar. I can create a "hoop over the drive shaft as the pickup point.

I keep reading that the side view of a 3-link is the same as that of a 4-link...so is the design the same??? If the geometry works in the 4 link, will it work the same in the 3? Running a long top bar should help the geometry too; as compared to a short top arm like the '05 'Stang.

Any feedback would be great...I'm itching to build this weekend.

Thanks!!!!!

Don

Pictures are here CLICK

[BillyShope]

Parallel to what? Parallel to car centerline in plan view or parallel to each other in the side view? If it's the latter, you can still have any antisquat value you want. (Parallel lines meet at infinity.)

I would suggest an asymmetric 3link. There's a setup spreadsheet at my site.

Side view antisquat determination is the same for 3link and 4links. 4link asymmetry, however, requires different antisquat values for left and right sides.

As for link length, it's always the longer, the better. As you pointed out, the Mustang gets by with a very short upper link.
http://www.racetec.cc/shope

[DNCII]

Thanks for posting Billy!!! Sorry, i haven't checked back to the site sooner.

When I said parallel, I meant two pairs of bars parallel to each other...like a 4-bar...as opposed to a triangulated setup.

I have now modeled a 3 link using your website...very useful: THANKS!

I am putting finishing touches on the model and then I will post it up for review.

Thanks again,

Don

[DNCII]

Okay, I finally got 3 models put together...incomplete, but the important stuff is there.

The panhard is not drawn in, but there will be one.

I would appreciate all the feedback I can get on the three...I can't decide for the following reasons:

The 4 link is the 4 link...nothing special...18" lowers, 17" upper bars.

The symmetric 3 link is great for packaging, The car is a '1932 ford sedan and since the car is so low it will have a tunnel anyway...no ability for equal loading though. 18" Lowers (I could go to 20s) upper is ~11" per Billy's link length optimizer.

The offset 3 link is right in the middle...packaging is so-so with a narrow footwell on the right side, but all of the benefits of the 3 link, etc. etc. Same upper and lowers as the symmetric design.

The attachments are 3-D .pdf files...if you have the most current adobe reader, you should be able to spin them around, zoom and all the fun stuff.

I'm really stuck and can't decide which way to go here...Please help me decide, especially if you have experience with any of them.

Thanks again,

Don

[BillyShope]

I didn't realize I could do all that with Adobe. Neat!

Keep in mind that you can retain driveshaft torque cancellation with a centrally located upper link by playing with the rearward mounting points for the other two links. See Page 40.
http://www.racetec.cc/shope