I'm planning to use a Concept One integrated steering box on a 71 LS6 race car. The car will be used for circuit type work, no oval track or drags. What steering ratio would you recommend 12/1 or 14/1?

The stock steering system has been rebuilt but remains vague on center and light to steer and owner wants to use an integrated box. The rules for the class prohibit a change to rack and pinion.

I've followed the installation of the Concept One box by another forum member and it seemed to go smoothly.

Any thoughts and advice would be welcome.

Joe

 

From what i saw, it throws off the steering geomtry, and can cause fitment problems, besides the welds. why not go with the jeep box

just read the 'no rack part'

 

It depends on average speed. As speed increases you want a higher number ratio to slow down steering responce.

At my local track I can do 2:20 second 4.2 mile laps. So my average speed is somewhat over 100 mph. I have 12/1 and I wish that it was much slower. When I have driven above 165 mph it becomes constant work to maintain a lane. If you add in some close cars and the buffeting turbulance you are always correcting

 

gkull,

Is 14/1 the same as stock or is the stock box slower than 14/1?

Is it possible to use the outer holes on the steering knuckles to slow down the 12/1 a little? I wonder how much effect that would have?


Joe

 

As gkull stated the Jeep box or concept one box runs off the power steering pump directly. There is no valve to alter the speed of the fluid that the pump spits out.
Therefore as your RPM's increase the fluid flow increases making your steering very touchy and darty. Steering effort is minimal and the 12:1 ratio is great on my car but its a street car. I don't like it at highway speeds or above b/c it is very figity especially with crosswind and road imperfections even though my wheel alignment is spot on.
As your RPM's drop so does the fluid and it is less figitiy and still minimal effort.
Do a search on here and you'll learn a lot about these units and the modifications needed. We haven't figured out how to integrate a Variable Control Valve into our non-ecu controlled vettes. Like the modern jeeps with this jeep box unit the computer controls a valve by reading the engines RPM's and lets more or less fluid to flow thru the steering box.

Also, if your racing you have to think about the fluid. You don't want it to boil/foam and become a problem. I'm running Redline racing power steering fluid to help with the heat from my headers since I didn't have many options of where to run my hoses from the pump to the hydroboost unit to the jeep box then back to the pump.

With the proper aftermarket power steering pump with optional valving for high RPM use (like a KRC Pump) you could make a jeep box work very well for you on the track. Just less steering assist at low rpm due to valving in the KRC steering pump. You also run a remote resoviour with the KRC pump so that could help with keeping the fluid cool. I ordered my jeep box from CorvetteSteering but for heavy duty use I would tell him (jim) not to redrill the mounting holes and replate your frame in that area for strength and then redrill holes to match the stock jeep box mounting. Much stronger that way. I don't like the way CorvetteSteering redrilled the holes then used sandwhich brackets to fasten it to the frame.

 

http://books.google.com/books?id=Ex2...Pc_24#PPA50,M1

I was trying to find some good info for you. I run a power steering oil cooler. Just a small unit on the return side. I kept melting the tank seals. I also use a smaller crank pulley because I have used 7500 rpm as a shift point.

I would install 14/1

It said in my book that I have: STEERING
Type recirculating ball, linkage-booster power assist
Turns lock-to-lock 2.9
Turning circle curb-to-curb 37.0 ft


The 2004 Vettes came with 16/1 because they needed high speed control

 

Thanks to all for your help.

It sounds to me like the 14/1 box would be a wise option, particularly given the owner is concerned about the "nervous" feel in a straight line at speed. The race car has a cooler for the steering fluid and seemed to be ok in practice. The LS6 is fitted with a race pump and we can change the pressure with substitute relief valves.

So my plan is to go with the Concept One 14/1 box, from VB&P, a manual center link, the VB&P bump steer kit and replace all the ball joints and tie rod ends with heavy duty units.


Joe

 

Make sure you get Moog ball joints and tie rod ends. Order them from Rock Auto. The quality of ball joints and tie rod ends from VBP has been questioned lately. To much chinese junk being sold as "heavy duty", even boxed in USA boxes. Be careful. On a race car don't take any chances, get Moog from Rock Auto.

 

Is there a supplier of Moog parts that ships overseas? What is Rock AUto's website?


Joe

 

http://www.rockauto.com/catalog/raframecatalog.php
Give them a call, they might ship overseas.
Or they might know of someone else overseas that can get you them.