Inboard Shock Arms

[fvkartguy]

I'm trying to decide what to do for the front suspension and looking for a source for the nifty shock rockers in case I want to do inboard shocks. Any ideas?
What is everyone else doing? The shock tower replacement, inboard, different mounting points...?

[rgu]

If you can buy into my premise that it’s best to get the car on the track and only then will you know what works or doesn’t -----you have but two choices.


1. 1) Use an outside shock mount kit like the one that SR sells for under $40


2. 2) Buy a set of pre-made remote shock mounts from someone who has bothered to do all the math like Campbell Motorsports or Mission Racecars. Expect to pay about $500+ for a kit. Because there are so many variables you’d also want to use the front shocks these manufacturers use. This will add several hundred more dollars.


If you don’t agree with my premise and you want to build your own, be ready to make plenty of bronze bearings, spacers, aluminum rockers retainers etc. A big challenge would be finding a mounting point on your frame. I would make a test model out of some easily worked material first before I starting cutting ¼ inch aluminum plate.

[LanceKTM950]

This is what is on my car...

[Bill Bonow]

Barett,

Here is the reality, they both work just fine. The simplest and most mechanically direct is outboard shocks. If you want increased "schwing" factor, inboard is for you. I would suggest outboard for any conversion to keep things simple.

Here is the system we put on Gomez Adams and it seemed to work well and get the shock out of the airflow.



Hope this helps.

[Jim Nash]

Doug Siem and Jason Steeb, among others, have shown a converted car with beam mounted shocks (outboard) can be very competitive (a bit of an understatement).

For what it is worth...The bellcranks on the MRC-09 prototype (see missionracecars.com) are .375 aluminum fabricated with a bandsaw, holesaw, and multiple files. They rotate on a .5 inch shoulder bolt in a bronze bearing, against needle bearing thrust bearings and washers on both sides. The pushrod mounts at the spindle are Evolution items purchased from Campbell Motorsports.

All those parts are pretty easy to purchase or fabricate. The more difficult part is the turned mount that is welded to the frame. The shoulder bolt goes an inch into the mount and needs to be a close fit to eliminate any play. It may still need to be shimmed (up and down) to get a perfect fit, but the tolerances need be close to begin with. PM me if you want more details.

If you fancy yourself as a designer/engineer, go for the inboard shocks. If you want to go racing, and focus your money and efforts on the things that will make you fast...go for the simple outboard approach. Call Jason, Doug, or Robert Guhde (Doug's engineer) and they will tell you everything they are doing to go fast. They are not shy about divulging information. My experience has been they figure they'll beat you anyway!

Jim