steering rack height

["Barry Dickinson&quo]

The quickrack I have ordered for my S4 is from a firm called Moss
International web site www.mossint.co.uk . The rack is a specially
strengthened one for racing hillclimbing etc and is designed for Triumph
Spitfire and Herald. The kit when it comes should include solid aluminium
rack mounts to replace the rubber ones on the original car. Apologies for
the delay in replying to your request I have been away for the weekend. When
the rack arrives I will be in touch again to let you know if it fits
properly. It should be 2.5 turns lock to lock.I have sent this to the list as I have
been unable to send You an Email to your server.

Regards

Barry

[types26/36]

Keep in mind that the Spitfire steering rack was modified for the Elan with
its different suspension geometry. If I recall correctly, the rack (not the
tube) is shorter and the tie rods are longer for the Elan. A Spitfire rack,
unmodified, will give terrible bump steer on an Elan if it will fit at all.

Randall

[rodbean]

Randall Fehr wrote:


Is that true? I've always thought that the whole thing was Spitfire except
that for the Elan, internal stops were installed to keep the range of steering
within the Elan bodywork, the Spitfire/Herald steering range being legendary.

Rod

[BrianMartley]

Hi,

I think you're right Rod, the "Classic & Sportscar Lotus File" book says
that the rack was Triumph Herald with Lock-stop mods to stop the wheel
hitting the anti-roll bar on full lock - I think these were simple spacers
to restrict the rack movement.

Brian

[rsfehr]

I believe Rod is correct about the stop - lock is limited (not rack
shortened as I claimed), but also the tie rods are longer than Spitfire.
This is why the tie rods were impossible to get for several years until JAE
had a batch made up recently.

-Randall


At 04:11 8/3/99 -0700, Rod wrote:

[BERGAMOTE]

----- Original Message -----
From: <[email protected]>
To: <[email protected]>
Sent: Tuesday, August 03, 1999 12:11 PM
Subject: Re: [lotuselan] re Query from Andres






The Elan steering rack is a standard Herald/Spitfire rack with three
modifications. A lock limiter is fitted either side of the rack and a spacer
tube is fitted (loose) on the near side of the car. The dimensions of all
three pieces are given in the workshop manual (section H figure 7). The
whole effect of this was to increase the turning circle of a Herald from 29
feet to 32 feet for the Elan.

I don't know about the Spitfire tie rods but the Herald ones were 1 inch
longer than the Lotus ones. It is not good policy to shorten these and cut
the threads down since the rods had rolled threads and thus cutting them
down does not give a true thread. The only solution to this part is to get
hold of original tie rods.

Carl Peters
Sprint
S/130/5
Stewkley, England

[rodbean]

Randall Fehr wrote:


Well I didn't know that! Glad I have spares. Boy this list is great. There is
a wealth of reference information available.

Rod

[jcocking]

The following is from Robinshaw's book, the Authentic Lotus Elan & Plus 2.
It has given the most info of any source I could find on the Rack Issue:
(quote on)

The rack-and-pinion assembly was a proprietary unit bought in from Alford
and Alder to a pattern supplied almost exclusively to Triumph, initially for
their Herald/Spitfire and subsequently the Vitesse and GT6 range of cars,
all of which were renowned for their tight turning circle. For the Elan
application it was necessary to achieve two objectives:

1. To limit the rack travel.

2. To decrease the overall dimension between the track rod end centres, to
cater for the Elan's narrower front track of 47.094in compared to the
Herald's 48.94in, a difference of 1.846in.

The first objective was accomplished by cleverly designing and fitting two
simple devices. To the pinion end of the rack the existing thin nut, which
locked the sleeve nut retaining the inner ball-joint locating cup, was
replaced by a combined locknut/limit stop (a 27/32in inside diameter spacer
sleeve approximately 9/32in long was welded to the existing 9/32in wide
locknut). At the other end of the rack a 1 3/4in long, 1 1/16in outside
diameter by 27/32in inside diameter steel sleeve was introduced, fitting
over the rack between the end of the rack tube and the existing ball-joint
cup, sleeve nut and locknut. Thus, the rack's total travel was reduced by
just over 2in (1 3/4in + 9/32in) to 4.73in from the Herald's standard
6.76in.

The second objective was largely accomplished by specifying shorter track
rods, which reduced the track rod end/inner ball-joint centre distance from
the Herald's 8.715in to 7.59in. This, complemented by other minor
dimensional differences, reduced the critical track rod end centre-to-centre
axial dimension from 44.67in to 42.68in.

There seems to be no apparent reason why the two special Lotus components
should not be fitted to an otherwise serviceable Triumph rack-and-pinion
unit on which each of the track rods has been shortened by about 1 in and
rethreaded 1/2in UNF. (quote off)

Great book. With the modifications mentioned, a conversion kit for the
Triumph unit could be created.

jeff

[types26/36]

Thanks Jeff for the research and correcting my claims from memory.

However I dispute this from the Robinshaw & Ross book:

The tie (track) rods have rolled threads as mentioned in a previous post.
The reason the threads are rolled rather than cut is that cut threads
severely weaken the part (big stress risers, see Carroll Smith), and a
steering tie rod is a red-critical safety part.

Randall

["Paul Lane, Jr."]

Rod,

1. Me too. 2. Me too. 3. Me too.

Paul

[email protected] wrote:

[abstamaria]

Randall,

Are the tie-rods available from JAE? Is there another source?

Many thanks.

Regards,

Andres
Manila
45/8439

[rodbean]

Well this seems to be the definitive steering rack treatise. Thanks Andres!

Rod






"A. Sta. Maria" wrote:

[abstamaria]

To add to the excellent information provided by Rod, Randall, and other Elan
Listers on the Elan steering rack, here is some information I recovered from
my Elan Journal (which I have been keeping since 1968 to record work done on
45/8439).

1. Comparison with Herald Rack. My rack was severely worn at about
45,000 miles, with razor-sharp teeth on the rack (probably never greased by
previous owners), . Since Triumph Heralds were assembled here before , I
was able to get a brand-new, old stock Herald rack. I found it almost
identical to the Elan rack, with the following differences:

(a) The Herald tie rod is indeed longer than the Elan tie rod by about
one inch.. For the record, my Elan's tie rod is 158mm end to end.

(b) The Herald housing (at least the older version) has no stop welded to
the housing tube to locate the rack clamp. This will be a problem if one
uses the original Elan clamp with rubber bushes, but probably not a major
issue with solid aluminum clamps.

(c) The grease fitting on the Herald rack is on the aluminum housing,
rather than on the large adjustment nut. One can still find the unthreaded
boss on the Elan rack's aluminum housing where this grease fitting used to
go.

(d) More importantly, the Herald rack's overall length was 10mm (over
1/4") longer than the Elan's (670mm vs. 660mm), but the rack is otherwise
identical. Since the rack ends are threaded with deep concave cups, I was
not sure if the difference was material. Anyway, I had the Herald rack
shortened and the ends machined to match the original. A straightforward
job.

(e) The pinion is also a little bit longer than the Elan's, but the extra
length is outside the housing.

(f) As noted in the Robinson & Shaw book, the Elan has the loose tube
spacer at one end and the thick washer welded to the nut on the other.

I used the Herald unit to refurbish my rack, using all the Herald parts
(including the pinion) except the housing and the tie rods. Seems to have
worked well.

2. Those Tie Rods. Inspired by the R&S recommendation to cut and
rethread the Herald tie rods, I did so. Twice. Definitely not recommended.
The diameter of the tie rod is not big enough to accommodate cut threads,
so, aside from the stress created by cutting, you will also not have enough
metal left in the threads. If you do not cut deeply (as I did the first
time), it will be difficult to thread the rod into the end.

3. 26R Modifications. If you use the larger 26R front discs with those
nice aluminum calipers, you will have to shorten the standard Elan tie rod
(by as much as 12mm -- about 0.45"). Otherwise the clearance between the
tie-rod end and the disc will be so small that the end's rubber boot will
contact the disc.

4. Possible (Non-Original) Modifications. If a correct-length tie rod
cannot be located, a good solution might be to fabricate a device that
screws onto a rack end and accepts a rod end (Heim joint in the U.S., Rose
joint in the UK). The steering arm tapered hole can then be drilled out so
that a rod end can be bolted on to it as well. Then all one needs is a
threaded bar (rolled threads please) that connects the rod ends on the rack
side and on the steering arm side. I have this system on my Type 23 (which
uses a shortened Triumph rack, of course). Now, such a system would be
"non-original" and illegal for vintage racing. Does anyone know of a
source?

I hope the foregoing trivia is interesting.

Regards to all.

Andres
Manila
45/8439

[types26/36]

One more note on the rack:
A common wear point that has not yet been mentioned is the bronze bush in
the non-pinion end of the rack tube. Depending on lubrication, wheel
balance, abuse etc. this can develop quite a bit of play. It can be checked
on the car - grasp the passenger-side tie rod inner socket through the boot
and move it radially. If there is perceptible movement or clunking, the
bush should be replaced. New parts are available. If the bush is severely
worn you will notice a definite improvement in steering accuracy after
replacement.

Europas tend to wear this bush much more rapidly than Elans.

Randall

[Foxie]

-----Original Message-----
From: Randall Fehr <[email protected]>
To: [email protected] <[email protected]>
Date: 07 August 1999 01:02
Subject: Re: [lotuselan] Steering Rack




Randall,

Your right there. I bought a "reconditioned" rack not so long ago and
shortly after noticed that the passenger side bushing was badly worn.

I have not seen this mentioned anywhere before, or replacement bushes
advertised.

Any idea where they can be got ?

Recent postings on this topic have been a real gem !

TIA

Sean Murray
Wexford
Ireland
1970 +2S