For my replica oldtimer car I'm having to alter a number of dimensions. Shortening driveshafts and propshaft already in hand, but I'm not happy with having an MX5 steering rack shortened - I'd rather use a rack from another car, preferably without power steering, and of recent manufacture.

Has anyone used a shorter rack, which would make sense if you are trying to have longer wishbones? I have to lose 252mm of track at the front. I can make the wishbones shorter if necessary but losing 126mm of each side whould shorten them more than I'd like.

Any information on steering rack lengths most gratefully received!

Adrian

https://www.locostbuilders.co.uk/forum/34/viewthread.php?tid=217692

You never know, might be worth a shot!
Ad

Ignore me, it's sold, I didn't scroll all the way down....

I'll get me coat!

Fiat Seicento/Cinquicento rack is very short, get one from a RHD UK car and it should work the right way around.

http://www.locostbuilders.co.uk/gallery/a751295-DSC00059.JPG

The car in the picture is a Furore by Russbost from this site. He may have more info on the rack such as dimensions and sources etc.



[Edited on 26/11/20 by nick205]

To make it work the other way around just turn it over, I use it upside down as my steering input to the hubs is the opposite way around to the Fiat.

If you need exact dimensions just give me a shout, I just buy off Ebay, the power rack is slightly higher geared (less turns lock to lock) the power is the electric type so doesn't interfere with the rack, just the column.

Thanks Adam, I appreciate your quick response and interesting link. I've taken to wearing my coat inside...

Thanks Nick, this does look as if it could work, in fact it's clearly a lot shorter which would allow me to have longer wishbones at the front The wheelbase is actually longer by 135mm and I'm getting the propshaft shortened by 250mm to bring the gearstick back behind the dash, so there will be room to have the inside wishbone pivots further inboard. By the way, I also like the inboard pushrod/cantilever/spring suspension arrangement - a nice way to adjust rates by changing rocker mechanical advantage and ride height with LH/RH threaded rose joints - surprised how few builders do this.

Cheers
Adrian

quote:

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Originally posted by Replicar328
Thanks Nick, this does look as if it could work, in fact it's clearly a lot shorter which would allow me to have longer wishbones at the front The wheelbase is actually longer by 135mm and I'm getting the propshaft shortened by 250mm to bring the gearstick back behind the dash, so there will be room to have the inside wishbone pivots further inboard. By the way, I also like the inboard pushrod/cantilever/spring suspension arrangement - a nice way to adjust rates by changing rocker mechanical advantage and ride height with LH/RH threaded rose joints - surprised how few builders do this.

Cheers
Adrian

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Thanks Russ, I've just noticed your reply, posted exactly at the same time as my reply to Adam and Nick. You've already answered my next question which was to be whether the steering rack can be turned upside down!! And in your case it looks like the column enters the rack on the left side (from the driver's point of view, (right side as you look at the picture). Which means I think I need a LHD steering rack for a RHD car. I'd welcome a check of my logic!

Yes please, dimensions would really help, ball joint to ball joint, and a link to the relevant part if you have one. I can only find the full length, tie rod end to tie rod end online. Oh, and nice motor you've built there :-)

Nick, it'll be a while before I go racing lol. I've been told that most aeronautics engineers are afraid of flying...

Cheers, Adrian

Just spotted https://www.ebay.co.uk/i/181363869120

Price seems okay for a new rack, so long as it does the job!

Don't know where you are based but I had my Sierra rack shortened by Gerry Hawkridge of Hawk Cars (or one of his subs) . worked a treat

Hi Simon, thanks for the suggestion re shortening a rack. I've actually just taken the plunge and ordered a LHD Seicento rack for £66 including delivery and the right to return within 100 days from "onlineparts" - including their 39% Balck Friday 39% discount.

Happily found this post with dimensions from 2014. https://www.locostbuilders.co.uk/viewthread.php?tid=195453

Not deadly accurate as I don't have a rack off the car, but ball joint centre to centre is around 400mm, sounds like you'll have your own to confirm with shortly anyway!

Many thanks, around 400mm would be ideal. I'm now slightly nervous that I've bought the wrong rack, but I can return it if necessary. The MX5 is about 640mm which is hard to check exactly but anything around 220 to 250mm shorter would work well

Quick update. Thanks to Russbost and Nick205 the Seicento steering rack I ordered has arrived and, without taking the boots off to measure exactly, it does indeed have a joint to joint length of around 40cm. Made my day