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Sierra De Dion on Book Chassis (sorry)
smdl - 23/10/05 at 04:50 AM

I know that this has probably been discussed to death, but I have just spent the last couple of hours searching and haven't found answers to my specific questions yet. So, please humour me as I am a new to this donor!

I am looking at a Merkur XR4Ti (North American Sierra) tomorrow, and am wondering about the width of the rear of the drivetrain in relation to a book chassis. The Sierra is obviously much wider than the standard book chassis, so I am wondering how this is accommodated? Shortened axles? Extreme FWD-type wheel offsets?

I have seen reference to using wide front wishbones to match the width of the Sierra rear, but how does this end up looking on the car (especially at the back)?

I am planning on running a Focus SVT (170 hp) Zetec with the Sierra Type 9 and want to use a GTS De Dion setup -- as long as it will work well and not look silly.

Again, sorry for bringing this up again. Any thoughts appreciated.

Shaun


flak monkey - 23/10/05 at 09:05 AM

A quick search would reveal your answer...

However,
Most de dion axles for the locost are designed to take the full length sierra driveshafts (GTS and MK make them and Rorty has just posted some designs)

The longer front wishbones dont make the car look out of proportion. The rear arches need to be wider as well, but most companies seel these, GTS included.

Hopefully that answers your question

David


JoelP - 23/10/05 at 09:10 AM

hi there. dont feel bad for posting this one, its often hard to find an old thread that really addresses your problem

if you are using sierra track, you can either make your car wider by a few inches, or just put bigger rear arches on. I believe (not sure though) that the brackets on the GTS de dion axle are spaced for a +4 car - i think its an option to have the brackets not attached though. Unless you make it from the plans yourself, in which case it obviously isnt a problem!

Front end, you can just widen the wishbones to match. Some people will point out that the geometry isnt quite maintained, but if that concerns you then you can redesign it to suit your purposes.


flak monkey - 23/10/05 at 09:20 AM

quote:
Originally posted by JoelP
I believe (not sure though) that the brackets on the GTS de dion axle are spaced for a +4 car - i think its an option to have the brackets not attached though. Unless you make it from the plans yourself, in which case it obviously isnt a problem!


AFAIK they are spaced for a standard chassis, but darren did make a few for people who were building +4's.

David


scotty g - 23/10/05 at 10:14 AM

The GTS de-dion will fit the standard chassis but he now also has a +4 chassis with de-dion as well so the choise is yours. Both have unmodified rears so are still 4" wider than an escort live axle but he still uses escort front racks.


smdl - 24/10/05 at 04:35 AM

Thanks, gents.

As indicated, I did do a search, investing quite a bit of time chasing down other threads and looking at people's photo albums, etc. What I found were a tonne of posts that were based upon what I would describe as previous or assumed knowledge -- that's how I knew that this topic had been discussed before.

Unfortunately, I never got back far enough to find the basic answers that everyone else seemed to already know, and I just ran out of time. Sorry for the duplication -- I'll try harder next time.

To respond to the suggestions, I am building my own chassis, and have the GTS plans on hand. However, I was planning to order the de dion kit from GTS, rather than trying to make it myself.

Can anyone steer me to a photo gallery where there are pictures that show a book chassis using Sierra de dion or IRS? I'd like get an idea of how the extra width looks.

One other question: Does the curve of the de dion tube encroach on the fuel tank area? It's difficult to tell from the one photo I have seen.

Thanks for your help! By the way, I did pick up the Merkur today for CAD $350.00 (GBP 167.17). No engine, but in pretty good condition (for my purposes) and with lot of semi-recent work done.

One step closer...

Cheers,
Shaun