welshboy
|
| posted on 3/10/06 at 05:24 PM |
|
|
help please
my dad and i have built a book chassis but we have not put in the front wishbone bars fu1 and fu2 yet becouse we cant decide to go with a escort rear
axle or a sierra is there big difference i have both it looks like the sierra 1 is bigger so not to sure if it will fit in the standerd book chassis
can any one help me please
|
|
|
|
|
DIY Si
|
| posted on 3/10/06 at 05:28 PM |
|
|
The sierra has a +4" track, so it depends wether you are making the fron track wider to match or not. Also, don't place those two tubes
until you have the wishbones as they can be an ar$e to place so the brackets are right.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
Mark Allanson
|
| posted on 3/10/06 at 05:49 PM |
|
|
Just like to add that it is not compulsory to have the front and rear tracks of equal width
If you can keep you head, whilst all others around you are losing theirs, you are not fully aware of the situation
|
|
|
DIY Si
|
| posted on 3/10/06 at 05:50 PM |
|
|
Sorry, didn't mean to make it sound like that. You don't have to widen the front at all, but having too narrow/too wide a front track is
not best.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
mookaloid
|
| posted on 3/10/06 at 07:00 PM |
|
|
Plenty of westfields have a narrower track at the front......
|
|
|
DIY Si
|
| posted on 3/10/06 at 07:07 PM |
|
|
Narrower than the rear track or narrower than something else? What I meant was that having it too narrow could affect the handling.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
welshboy
|
| posted on 3/10/06 at 07:47 PM |
|
|
so the sierra is 4in wider then the escort is that right ? so is there anywhere i can get plans to fit the sierra axle and if i fit the sierra will i
need wider arches and is there anything else id need to alter ? and id just like to say thanks to everyone for there help we are new to this first
time builders !
|
|
|
DIY Si
|
| posted on 3/10/06 at 07:51 PM |
|
|
Are you aware that the sierra doesn't actually have an axle, like the older escort stuff? It's a diff with drive shafts which have semi
(?) trailing arms in the sierra. These are normally converted to use either an IRS or De-Dion set up in a 7. Either way, you'll need wider
arches since you have a book chassis.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
welshboy
|
| posted on 3/10/06 at 08:03 PM |
|
|
yep i know that iv got both sat on the workshop floor just cant decide what to use escort looks easyer becouse we could follow book for the front then
and would be standerd but if we used sierra i did not know if we needed to widen the front wish bones does any one know where i could get plans to
use sierra if we decide to
|
|
|
DIY Si
|
| posted on 3/10/06 at 08:08 PM |
|
|
There's this one for the IRS.
Damn it's too big.
Try here. This is FlakMonkey's website and has many useful little
downloads/programs, such as a tube mitre/fishmouth generator.
[Edited on 3/10/06 by DIY Si]
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
welshboy
|
| posted on 3/10/06 at 08:24 PM |
|
|
thanks very usefull whats the differance between the de dion and an irs ?
|
|
|
DIY Si
|
| posted on 3/10/06 at 08:29 PM |
|
|
You're best bet is to search on here. The irs uses wishbones and the de-dion uses a five link way that a live axle does, but the axle tube
merely connects the hub carriers. In both cases the diff is attached to the chassis, and the drive shafts are out in the wind. The live axle and
de-dion are better on track, with live being best, where as irs and de-dion are better on the road due to a lower unsprung weight. This is also a
long, much discussed topic and is somewhat open to personal preference, so expect to find many different views and opinions.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
jonbeedle
|
| posted on 4/10/06 at 08:12 AM |
|
|
Go with the Escort axle. It's easier and it's more in keeping with the original Lotus 7....if that's what you want!
"Everyone is entitled to an opinion however stupid!"
|
|
|
NS Dev
|
| posted on 4/10/06 at 08:20 AM |
|
|
agree, if you don't know the answers to those questions then go with the escort axle.
It will be a very good car, and you are probably better handling wise to have a matched narrow track than an unequal track front to rear.
Retro RWD is the way forward...........automotive fabrication, car restoration, sheetmetal work, engine conversion
retro car restoration and tuning
|
|
|
MikeRJ
|
| posted on 4/10/06 at 09:48 AM |
|
|
Have to agree with Nat, use the Escort axle.
If you are having worries just over the difference in track, then I get the feeling that you may not realise what's involved in using the Sierra
components. The only parts you should be looking at using are the diff, the driveshafts and the bearing carriers, hubs, brakes etc. The main beam
and the trailing arms are not suitable for a Locost.
If you have built a book chassis, then basicly you can not fit IRS without chopping the rear end off and pretty much starting again.
Alternatively you could buy a De-dion axle and this is much easier than using IRS as the same trailing arms are used, but you will still need to make
some modifcations to the rear of the chassis.
|
|
|
welshboy
|
| posted on 4/10/06 at 06:27 PM |
|
|
whats the difference between a de dion and an irs ?
|
|
|
DIY Si
|
| posted on 4/10/06 at 06:55 PM |
|
|
This is an example of a independant front suspension. The rear just has a drive shaft and a different hub.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
DIY Si
|
| posted on 4/10/06 at 06:58 PM |
|
|
Try again
Bit like the front really. Well tht's what the pics is, but the overall set up is the same.
[Edited on 4/10/06 by DIY Si]
 
Rescued attachment mojo2fntsusp.jpg
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
DIY Si
|
| posted on 4/10/06 at 07:00 PM |
|
|
This is de-dion
 
Rescued attachment de-dion.jpg
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
Peteff
|
| posted on 4/10/06 at 07:52 PM |
|
|
Here's a simplified diagram
The blue bar is solid and joins the two wheels together and the diff is fixed to the chassis.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
|
|
|
MikeRJ
|
| posted on 4/10/06 at 08:19 PM |
|
|
quote:
Originally posted by welshboy
whats the difference between a de dion and an irs ?
The De-Dion axle is very simmilar to a live axle such as the one from the Escort in that the two wheels are directly linked together, so movement of
one affects the other to some extent. The main difference is that instead of the differential being part of the axle, it's fixed drectly to the
chassis, and driveshafts with flexible joints (e.g. constant velocity joints) are used to transmit power to the wheels. The idea is that it reduces
unsprung weight, which is important on a light vehicle like a Locost in order to get good handling on typicaly rough and potholed British roads. On
smooth tarmac it has little or no advantage over a live axle.
IRS is technicaly any rear suspension system where the two wheels can move independantly of each other. The standard Sierra rear suspension is an IRS
system. However, in terms of Locosts when people talk about IRS they are usualy talking about a system that uses double wishbones just like the front
suspension does.
IRS is far more complex to design as it's behaviour when the suspension compresses or the car rolls is crucial to the handling of the car. With
a live axle or De-Dion the wheels always remain at a fixed angle to each other irrespective of how juch the chassis rolls in corners etc.
With most IRS systems the camber of the wheels changes as the suspension is compressed and this behaviour has to be properly controlled to prevent
undesirable handling traits.
|
|
|
