I am a new builder, have bought donor Sierra and hope to build IRS type Locost using Tiger Avon rear suspension details.

I haven't dismantled the donor as yet, my question, is it possible to use the Sierra rack and front hubs. I would imagine an Escort steering rack and Cortina hubs would be very difficult to obtain at a reasonable price.

John,

I've used those parts on my chassis (4" wider than book) BUT

a) I chopped about 8" from middle of rack. When I can I'll measure distance between hole centres to give you a more accurate idea. You will want to get your chassis built so you can position your rack in the correct place (the tca balljoints need to be in line with the inner w/bone pivots), then make/purchase rack to correct dimensions. Obviously if you buy a chassis, you can get things like this already designed to fit:-)

b) As a consequence of a), I had to add about 1.25" to track control arms

c) You will need inserts to replace the McP Strut in top of uprights, so a balljoint can be used (have a look in my photos in the photo archive at pic 10000011 (Front suspension), you can clearly see the shiny adaptor (one side has ball joint, other didn't!)

Hope this of some help.

ATB

Simon

Simon, is your chassis 4" wider throughout, including the front bit? Difficult to tell from the pic. Also, what lower balljoints did you use?

John

John,

Yep, all chassis cross pieces, including front, 4" wider than RC book. I'll put up pick with standard nosecone which should help show difference.

As for lower balljoints, couldn't tell you what they're from, but they were bought from Luego with front w/bones, bushes, brackets, nuts/bolts etc as a set. I'll put "closeup" pic on here if you like. I have the boxes for them where the car is, so will leave posting under here over w/end of make and part number if it helps.

ATB

Simon

Simon thanks for information, I could see the Sierra hub setup quite clearly from your pics. I also noticed some similar Sierra hub pics posted by webmaster.

Is the modification to the Sierra rack a straight forward cut and weld job or is there more to it.

John.

John,

After I've posted this I'm going to start posting some more pics to the archive, including one with me in it, so you can all put a face to a name. Aren't we lucky. Probably not

As for rack I intend to purchase a professionally welded item, when it's required. This was the first time I'd welded ally, and have absolutely no faith in it. I've only done it, so I can move car around!

As far difficulty in shortening rack, please bear in mind that the rack casing is made of (really crap)ally, so unless you have access to an AC TIG or relevant gas welder, it's impossible to do yourself. Also, the rack bit itself will need shortening, and the end tapping for track control arm to screw into.
I cut that bit off, chopped a bit out of the middle and welded the threaded bit on again.
I think the general idea for the casing, is to put it in a lathe turn a section down, and sleeve it, then weld sleeve.

Not exactly ideal, but ok for pushing around.

John (interestedparty)

The lower balljoint is Austin Maxi - AP Lockheed part no.TC32 / R50GK (those are the two numbers on the box!!)

Hope this helps chaps

ATB

Simon

Simon,

Thanks for the info, very helpful.

John.

Yes, thanks from me too. I believe that MK use the Maxi balljoint as well, and that the taper in the bottom of the Sierra strut needs to be changed for this joint to fit.

John

I did something similar, extended track rods using adapters, cut the alu casing with a hacksaw and took out required amount from centre and rewelded with a sleeve, then turned off end of rack in a lathe and recut internal thread. Only problem I had was the quality of the cast casing is very poor and when I tried to weld up two halves without sleeve they were nowhere near round and didn't match up.

I did something similar, extended track rods using adapters, cut the alu casing with a hacksaw and took out required amount from centre and rewelded with a sleeve, then turned off end of rack in a lathe and recut internal thread. Only problem I had was the quality of the cast casing is very poor and when I tried to weld up two halves without sleeve they were nowhere near round and didn't match up.