Power steering?

[Cobra #3170]

Originally Posted by CSX3183

You must be kidding, PS on a Cobra, only a 98 lb. weakling would need PS.

Try driving a Cobra with less than 1 turn lock to lock and 315x30x18 fronts and you will understand why power steering is needed.

I used an Appleton Rack with modified end points (lengthened to center the rack and correct bump steer). I fabricated a mount to locate the rack and allow it to bolt to the original rack location. I also fabricated new tie rods to adapt the rack to the Cobra steering arms and used a stock GM pump with remote reservoir. The pump mounts to the LH cylinder head with a bracket I fabricated. I use a short ribbed belt to drive the pump at about 1/2 engine speed. There is also an adapter that matches the stock steering shaft to the Appleton rack. Quite a bit of work but it has worked well for over 15 years now with about 3 rack rebuilds required over the years and two pumps.

[CSX3183]

The difference btw you and the average Cobra owner is more than apples to oranges, it's like night and day. You sir are in a class of you're own, and why you have PS is completely understood.

The average owner or even occasional track guy, doesn't need it, I mean they didn't have it back then, for racing, with somewhat fatter tires, were all the drivers menly men, and now we have girly men?

Originally Posted by Cobra #3170

Try driving a Cobra with less than 1 turn lock to lock and 315x30x18 fronts and you will understand why power steering is needed.

I used an Appleton Rack with modified end points (lengthened to center the rack and correct bump steer). I fabricated a mount to locate the rack and allow it to bolt to the original rack location. I also fabricated new tie rods to adapt the rack to the Cobra steering arms and used a stock GM pump with remote reservoir. The pump mounts to the LH cylinder head with a bracket I fabricated. I use a short ribbed belt to drive the pump at about 1/2 engine speed. There is also an adapter that matches the stock steering shaft to the Appleton rack. Quite a bit of work but it has worked well for over 15 years now with about 3 rack rebuilds required over the years and two pumps.

[Dominik]

The OPEL Corsa-C, built from 2002 to ? has an electrical power steering. The beauty of this unit is, the steering rack intermediate shaft has a "Double-D" (lol) universal (which is a flattened 3/4" / 19 mm shaft, milled double-flat to 9/16" / 14 mm. This should be easily adaptable to any steering rack.

You may want to check your castor and (what's it called, roll radius?) to ease on your steering efforts. Essentially your backspacing of the front wheels could create too much leverage on the steering. I also found that old tires turn very badly.

And for those who use i.e. a MGB steering rack, it comes in two different ratios. Not sure what mine had, but with a 16" steering wheel I could steer the car with one hand while pushing it around in the yard - until I created to much friction based on the Ackermann settings.

Hold back your horses when somebody asks. I inquired once for an automatic for a GT40 and got useless comments. It was for a one-armed owner (which I cold have mentioned, I know).

[Cobranut]

Originally Posted by Cobra #3170

Try driving a Cobra with less than 1 turn lock to lock and 315x30x18 fronts and you will understand why power steering is needed.

I used an Appleton Rack with modified end points (lengthened to center the rack and correct bump steer). I fabricated a mount to locate the rack and allow it to bolt to the original rack location. I also fabricated new tie rods to adapt the rack to the Cobra steering arms and used a stock GM pump with remote reservoir. The pump mounts to the LH cylinder head with a bracket I fabricated. I use a short ribbed belt to drive the pump at about 1/2 engine speed. There is also an adapter that matches the stock steering shaft to the Appleton rack. Quite a bit of work but it has worked well for over 15 years now with about 3 rack rebuilds required over the years and two pumps.

How does a steering rack even get full lock with less than 1/2 turn of the wheel? The pinion would have to be enormous, or the steering arms extremely short to achieve that.

[scottj]

Originally Posted by Cobranut

How does a steering rack even get full lock with less than 1/2 turn of the wheel? The pinion would have to be enormous, or the steering arms extremely short to achieve that.

I had 3/4 turn lock to lock with an 3.9"/turn Appleton rack and 5" steering arms. I've also run a 4.5" Sweet rack that was noticeably quicker. Pinion sizes were approximately 1.2" dia and 1.4" dia. These were on dirt late models. A standard road race rack is 2.0"/turn while an autocross rack might be 3.14"/turn. Easy-peazy...

[Cobranut]

Originally Posted by scottj

I had 3/4 turn lock to lock with an 3.9"/turn Appleton rack and 5" steering arms. I've also run a 4.5" Sweet rack that was noticeably quicker. Pinion sizes were approximately 1.2" dia and 1.4" dia. These were on dirt late models. A standard road race rack is 2.0"/turn while an autocross rack might be 3.14"/turn. Easy-peazy...

Thanks. I guess I wasn't really thinking about the circumference of the pinion being the rack movement in one turn.

My Cobra has an MG rack that gives about 2 turns lock to lock. Much quicker and steering effort would get pretty high when parking.

My race car's rack ratio and steering arms are set by the rules. It has about 1.4 turns LL. Of course, it only weighs about 1,300 lbs with driver.