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Here is how the front suspension will be done:

Thats a good design, pretty basic but it works. I ran into a problem trying to get a pushrod front suspension though. Everywhere I placed my pushrods or my shocks I ran into something, steering rack hoses etc..

The way I should have designed my front suspension, and I still might add a removable front suspension substructure so I can switch between pushrod and the current setup. Do the A arms first, have the arms and steering knuckle set up, then the steering rack with the tie rods, then the suspension. It should go fairly smooth if you do it that way. The steering rack is pretty set as to where it wants to have the steering column come from

You may want to go with a different rocker ratio than a 1:1, as the motorcycle shocks really don't have a very large range of motion/travel (maybe an inch?). I don't have my Suspension Analyzer file here with me at work but if my memory serves me correctly, I ended up somewhere around a .75 - .8 motion ratio that got me about 3.5" of total wheel travel within the allowable travel of the shock.

Also, keep in mind that you want to keep the angle that the shock makes with a line intersecting it's mounting point on and the pivot of the rocker LESS than 90 degrees at full compression. Otherwise you end up with a falling wheel rate.

The motion ratio also helps counteract the REALLY high (700+ lbs/in) spring rate of the bike coilover, getting it back to a more reasonable wheel rate. That being said, when budget allows, I'll be buying replacement springs of the appropriate diameter to get the wheel rate and front and rear frequencies back within a liveable range.

-Erik

I have 2.5" of travel on my r6 shocks.

Good deal. I was seeming to recollect that it was less than that, but I'm glad to hear that's not the case.

emohn,

Thanks for the great info!! I knew the bike coils were stiff, but not that stiff! Do you know of any resource online where I can look up the stock coil rates for the zx7r and r6 springs? As long as I know that value, I can calculate out the linkage needed to drop it to a useable rate at the wheel.

Also, I didnt think of the falling rate issue.. that is very good to know. I'll make sure and set up all the shocks in this manner.

As for the rocker ratio, I think I may try reusing the rockers that are coming with my r6 shocks:



The long corner will hold the pushrod from the wheel and will give me some more reduction in the rate.

Here is a suspension design that I did for the frontend based off the suspension pivot points that will be on the actual car..



YOu can see the bellcranks and shocks. This will become more accurate when I have measurements for everything.



Hard corner with some body roll.. I think I need to dial in a little more camber under compression.

Here are the rear suspension models. Note that the trackwidth IS the same front to rear, just looks different due to the lack of cropping on these images..






Also, if anyone wants the SusProg3D file, here it is:
http://members.cox.net/desertpir8/locost_bellcrank2.s3d

You will need the latest version of SusProg3D to view/manipulate it (v 4.75A). Feel free to use it any way you want. But, I do need to note that the dimensions are NOT perfect and may or may not be useable. The dimensions were taken with a tape measure and are mabye within .5". This is just to help visualize how this will work for me, and wont be used necessarily for construction.

I measuered my r6 shock, 2 1/4" until the bump stop hits

thanks! Also need the static (unloaded) eye to eye length on that shock. THough, I'll have my own here soon, so can get all that when I get the shocks in the mail.

Roughly 12.5" from the center of each bolt

Got one of the front A arms done:



Almost looks like a car in this pic:


The new front A arm.. needs some finishing still, but its about 90% done right now.


Got the lower mounts tack welded on:


Another view:


The view from the driver's seat:

Got the other lower A arm fabbed up last night. Turned out much nicer than the first, but I'm happy with both of them. They are identical and fit the chassis like a glove, and better yet, it looks like a car now!.

Today, I'm ordering a big box of high misalignment heims from McMaster-Carr for the steering and upper balljoint on the frontend. I also have to pick up eight heims for the suspension pushrods front and rear. This is gonna get expensive.

Just placed an order through the guys at www.Coveland7.com for a full set of handmade aluminum fenders and a replica Lotus Seven nose.

Over lunch, I picked up a full set of 4 right and left hand threaded heim joint pairs for the pushrods at all 4 corners. I also ordered 4 high misalignment heims from McMaster Carr for my steering tie rods.

Its been a very expensive day, but will be well worth it to get the car together.

Hmmmm GUINNESS!!!!

Looks like you got a nioce build going on here. Keep the updates coming.