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TypeRboy
05-26-2003, 04:00 AM
Can anyone tell me if the 7 rack steers from in front of or behind the front wheels..ie is the rack on top of the input shaft pinion or below it.. It could be the 7 rack will work for me.. I need a rack that I can mount behind the wheels...

Does anybody also know what other BMC cars this or the Elan rack fit? images/icons/confused.gif

aeronca65t
05-26-2003, 08:53 AM
I was always under the impression that Sevens used a Spitfire/Herald rack (because the front suspension is Triumph-based)

Dave Thielke
05-26-2003, 09:59 PM
Right, seems that all the Lotus cars I was around, Elite, Elan, 7, Europa and the early race cars all used various configurations of the Harald rack and pinion set. Some were turned over, or r/h drive units on l/h drive cars to change from in front to behind the axle etc. as the situation required. Some had tube spacers to limit the travel, others had different rod lengths. This was a very versatile assembly and used by a lot of race car builders.
Looking thru my old Elite manual, it shows the rack and pinion mounted behind the trunions with the pinion above the rack. I'm quite sure the 7 used the same layout.
Dave T

TypeRboy
06-03-2003, 12:50 AM
Ha ha.. I think an Elite rack would be harder to find than an Elan rack.. Yes it looks like the Spitfire rack in RHD is the way that I have to go..

Now I just have to find one..

Super 7
06-03-2003, 09:41 PM
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by aeronca65t:
I was always under the impression that Sevens used a Spitfire/Herald rack (because the front suspension is Triumph-based)<hr></blockquote>

The rack, spindles, and upper link are Spit. The A arms and sway bar are fabricated. I had to muy a new rack for mine years ago, after a crash. The vendor said it was a modified Spit rack, but I don't remember the nature of the modification.

P.

TypeRboy
06-09-2003, 02:33 AM
For sure the mod is changing the turning ratio fron 3 and 3/4 for the Spit to 2 and 1/2 for the Lotus.. A neat trick that I'm going to try with the Spitfire rack.. graemlins/hammer.gif

aeronca65t
06-09-2003, 09:05 AM
Part of the reduced number of turns on the Lotus is because (I think) it's wheels hit the "stops" sooner (it doesn't turn as sharp as a Spit...almost nothing does) and I'm pretty sure the steering arms on the Lotus are shorter. The actual rack and pinion ratio may be the same.

TypeRboy
06-09-2003, 08:20 PM
Hmmm..That might be..I don't have a spit rack to compare with.. My rod ends are 6 inches long and there are no limiting sleeves on the rack ( Lotus )I don't know the turning circle on the Lotus, but it it not overly tight for such a small car. Still, one more turn of the rack either way would just about bring the front wheels perpendicular with the rack.. Now that would be a tight circle..Ha ha..

sevenhead
07-31-2003, 05:19 AM
When I assembled my 7, the rack was a new Spitfire/Herald unit. The only modification that I made was to add limiting collars.

TypeRboy
08-02-2003, 11:34 AM
Nuts,I found out that it won't work..The tie rods have to be the same length as my lower control arms for the bump steer issue, so that means I need a shorter ( or modified ) rack. Back to the drawing board.. images/icons/rolleyes.gif