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A couple of queries...
Dan. - 12/8/10 at 12:07 AM

Firstly the steering rack
When a rack is 'shortened' can this be seen from the outside (i.e. the casing is shorter?) As I built my indy part built, with the rack that came on the car it turns 4.5 turns as per the normal sierra rack, but both left and right lock are not limited by the rack but by the wheels turning so far they hit the wishbones, with this much movement it will probably be able to do a U turn in its own length.... which cant be right? more importantly Im sure it will fail IVA... So is this because th rack has not been shortened?

Secondly the pedals
These I presume are MK supplied? I ask as I only have two of the 3 bushes for the pedals so need to source another..

Unimportant but may as well ask as it could save me time in the morning... What size and length bolts do I need to attach the type 9 bell housing to the pinto block?

Thats it for now, no doubt have more questions as I crack on with the build...


snapper - 12/8/10 at 07:08 AM

Shortening the rack usually refers to cutting the ends at the ball joints back, cutting the casing would do little.
Most people need to add rack arm extensions to make the rack ends meet the steering arms on the hub.
The methods of reducing steering movement are varied some making an ally spacer that clamps on the steering rod others a simple jubilee clamp.
4.5 turns seems a lot, the Sierra has 2.7 standard and about 2.4 for the power steering rack


snapper - 12/8/10 at 07:18 AM

Shortening the rack usually refers to cutting the ends at the ball joints back, cutting the casing would do little.
Most people need to add rack arm extensions to make the rack ends meet the steering arms on the hub.
The methods of reducing steering movement are varied some making an ally spacer that clamps on the steering rod others a simple jubilee clamp.
4.5 turns seems a lot, the Sierra has 2.7 standard and about 2.4 for the power steering rack


adithorp - 12/8/10 at 08:11 AM

quote:
Originally posted by snapper

4.5 turns seems a lot, the Sierra has 2.7 standard and about 2.4 for the power steering rack


Are you sure about that. I thought Sierra racks had a lot more turns than that lock to lock.

adrian


Davegtst - 12/8/10 at 08:36 AM

My rack has been shortened by cutting a piece out of the casing then welding it back together again. Mine turns about the same as yours and it will need some form of stop to stop the wheels hitting the wishbones, not sure what to do about this yet. It should fail the IVA if the wheel fouls anywhere on the car.

The pedals are MK supplied including the bushes.


rb968 - 12/8/10 at 08:57 AM

I had the same problem with the lock on my shortened rack. Some suggested using valve springs to prevent the rack travelling to full lock but as was pointed out the spring could stick or jam causing the steering to jam or stick.

So had the machine shop at work to turn me 2 spacers from aluminium.
Steering rack spacers
Steering rack spacers


These fit over the shaft of the rack inside the end of the rack housing like this.

Steering Rack spacer
Steering Rack spacer


The joints on the ends of the rack are threaded into the shaft (and mine had a load of loctite on them so we had to warm them up to get them off). Think mine were 30 mm width so it took a fair bit off the lock but it was like a black cab previously!

Rich


Davegtst - 12/8/10 at 10:36 AM

Don't suppose you could get 2 more made up that i can buy off you please?

[Edited on 12/8/10 by Davegtst]


Dan. - 12/8/10 at 10:52 AM

looks like I will be making a couple of sleeves to stop it turning too far then and contacting MK for a replacement bush

Thanks guys


Bluemoon - 12/8/10 at 01:01 PM

See my comments at the end of this thread

http://www.locostbuilders.co.uk/viewthread.php?tid=140384

You will want the rack to be the correct length for the suspension pickup points to minimize bump steer; and then you will dial out the bump steer by moving the rack up and down with spacers when setting up the suspension latter... This why it's made shorter on the Indy; both the case and rack are shortend, the rack is not made "quicker" (i.e. less turns lock to lock) by this operation.

Dan

[Edited on 12/8/10 by Bluemoon]


Dan. - 12/8/10 at 06:20 PM

cheers I hadnt seen your comments on the other thread