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Which base chassis for a V6 4x4?
w.olly - 8/4/12 at 05:06 PM

Hi all, i have been looking around for which chassis to use, or build a one off one, i would rather build say a Ron Champion locost and modify if possible.

So is there a good chassis to go with to modify for the 4x4 V6 setup, oh and it will be sierra running gear, or best to build a one off?

All help on the chassis build is mucho welcome folks.


cheers

wolly


big_wasa - 8/4/12 at 05:28 PM

I would build your own but a haynes would be better than a Ron chassis as its wider.

You will have the transfer box where your feet and pedals want to be.


w.olly - 8/4/12 at 05:34 PM

Could the Locost plans be widened to suit though as there will be a lot more adjustments needed i guess.

Is there a build plan for the haynes as with the Locost?

cheers

wolly


edit to say i just googled and they do a book aswell

[Edited on 8/4/12 by w.olly]


samjc - 8/4/12 at 05:44 PM

A +442 chassie would meet the criterial for running gear to fit but may need to replan the transmition tunnel to suit but then again my design chassie has my type 9 gearbox almost ending flush with where the pedals are mounted.


samjc - 8/4/12 at 05:46 PM

Quick question how will the front suspension and drive shafts goas had ideas myself but couldnt work it out.


w.olly - 8/4/12 at 06:59 PM

quote:
Originally posted by samjc
Quick question how will the front suspension and drive shafts goas had ideas myself but couldnt work it out.



I am not sure how you mean, but front suspension will be inboard, i hope, independent and the drive shafts from the front diff, is this what you mean.

[Edited on 8/4/12 by w.olly]


ali f27 - 8/4/12 at 08:02 PM

purdy just used a haynes very little modding really easy to do just need to sort steering out


Liam - 9/4/12 at 04:21 PM

Hi w.olly

Probably any design out there will suit with a few mods to accomodate the 4WD. But a chassis with a bit more room in it will make things easier in general.

My chassis started off with the book dimensions but let the tapered sides come back another 3" (which made it 1" wider in the cabin). Kept the overall length the same so it ended up 3" shorter in the cabin/footwells and 3" longer in the engine bay. This gave me some extra space to play with in the engine bay and made the overall proportions more Caterham-like. The book locost is really long in the cabin in comparison.

Tunnel is wider at the bellhousing area so I could get my engine really far back, then I added an IRS rear setup and changed the front suspension area too. Had to loose the engine bay diagonals which is why I went for an over the engine brace to restore rigidity (actually hugely increase rigidity - my chassis is 4-5 times the torsional stiffness of a book chassis). Cos my footwells are narrow I panelled out a bulge to give more pedal space (can see this in my photo archive) - this is a trick Dax do in their Rush which also has a really wide bellhousing area to accommodate big engines positioned nicely far backwards.

But you could just as easily use a standard design with only minor mods to the chassis around the tranny tunnel (to allow for the transfer box front output) and around the front suspensiona area for the front diff. Book would do, but Haynes or a Book +442 might be a better shout for you as you plan to use the big 24V engine. The general principal you can follow is to do your outside tubes and rear-end to a standard design as this wont change, then you can to internal tubes like the footwells and tunnel, etc however you want to fit around your engine and transmission - literally build around it.

Dax have a different approach to the front diff than me or others which is something to think about too, as is getting your steering column over/around the front diff.

I've got a bunch of photos of a Dax Rush 4x4 build if that's of any use too.

Liam


jacko - 9/4/12 at 05:27 PM

Description
Description

This is inside a 4x4 wheel Dax
Jacko

removable footwell panel
removable footwell panel

And this is in Liam 's car
Very similar

[Edited on 9/4/12 by jacko]


Liam - 9/4/12 at 05:31 PM

That's John Cellier's V8 Quadra. An awesome build that inspired me to stick a nice V engine in mine - my original plan was a C20XE or LET or something like that. That's the car I have some build photos of.


ali f27 - 9/4/12 at 06:04 PM

Hi your going to need a standard sump as well we cut the 4x4 sump up to make mountings for the front diff worked really well need to ask purdy how to make the steering work as diff wont allow you to put rack where it normaly goes and difficult to sort bump steer cheers Ali


w.olly - 10/4/12 at 06:54 PM

Thanks for the info Liam, as i though then, not that much to change, the main being getting the steering inplace infornt of the diff, and loss of foot well space, yes i think i will make the outer chassis and then sit the running gear in place and go from there.

Doesnt look to loose to much to make to much a apin the the pics Ali gave, cheers mate.

Is there any reason i cant widen the cockpit by say 5 inch, or enough to get good footwell space, i know the front bulkhead would be wider than the front end and have a big taper to the grill, but that not a bad thing as we make our own bodies anyway.

[Edited on 10/4/12 by w.olly]


w.olly - 14/4/12 at 05:14 PM

Liam, how about them Dax 4x4 pics you have, i need to see what to do with the steering before i get into this. I think thismis the main point, or problem with a 4x4.

I see your (Liam) steering is over the side of the engine and down over to the steering rack, is that 4 UJ`s? Would this not give a bit of play in the steering?
I have been looking at power steering options, not that its needed but i thought it could help out with the set up.



Wolly


Liam - 16/4/12 at 07:26 PM

This is the thing with the steering column...

If you want to put the front diff in the same left-right position as it is in the Sierra, which allows you to keep the standard intermediate (through the sump) shaft and standard driveshafts, and you want to use the locost first choice of an Escort MKII steering rack (well was first choice back in the day - not sure now), you have a small problem which is that the steering column needs to climb over the tallest part of the front diff. You can just about see that in this pic...
Description
Description


My solution is to climb over with one or two more UJs than most steering columns get, but it works fine. The bottom part of my column is from a MKIV Escort if I recall (Chris W gave it to me ).

Dax's solution is to move the diff inwards towards the centreline a few inches so that the steering column only has to climb over the driveshaft output of the diff, which can be done easier with a small extension on the rack and a fairly 'normal' steering column. You can just about see that here...
Description
Description


This of course means you have to extend the OS driveshaft a few inches and they get rid of the intermediate shaft assy and extend the NS driveshaft right to the diff. You need to machine the insert on the NS of the diff to accept the driveshaft and an oil seal (i.e. to match the other side) so that a driveshaft can plug in.

Another solution if you want to stick with the standard diff position and driveshafts, best if you're starting with a wider chassis, is to just use a wider rack with the output further to the outside than the MKII Escort rack. I dunno what would be suitable though - what do people use in +442s or Vientos, etc etc?

Hope that helps.

To answer your U2U question, I'm not personally aware of any finished 4WD locosts except for the one Ali F27 keeps mentioning that his mate built. Not sure if the guy still has it and dont remember seeing any photos of it and how it was built. So come on Ali F27 - got any more info?


w.olly - 17/4/12 at 12:21 PM

Helps a lot that Liam, cheers mate, the best thing i can do is get all the running gear on the bench, measure up an dgo from there. i am sure i can come up with something
I have got my Roadster book now, well my mate has as he has borrowed it already, Once the runnin ggear is in place i will size the chassis up towards it and see what needs altering.

Liam, i am thinking i will be able to keep the rear end as in the book as this will be the same, is this what you did? I know i should just do as i just saud above but things just pop in my head and i like to ask.


w.olly - 17/4/12 at 12:21 PM

Helps a lot that Liam, cheers mate, the best thing i can do is get all the running gear on the bench, measure up an dgo from there. i am sure i can come up with something
I have got my Roadster book now, well my mate has as he has borrowed it already, Once the runnin ggear is in place i will size the chassis up towards it and see what needs altering.

Liam, i am thinking i will be able to keep the rear end as in the book as this will be the same, is this what you did? I know i should just do as i just saud above but things just pop in my head and i like to ask.


ali f27 - 17/4/12 at 03:08 PM

hi Liam have a look at user name purdy photo archive


Liam - 18/4/12 at 04:42 PM

Yeah w.olly you can make the rear end exactly the same as any existing plans for a RWD Sierra based chassis. Your 4x4 donor car will have a rear 7" LSD with bolt-on shafts and disk brakes.

Mine's completely different cos there were no Sierra-based double wishbone rear end plans back in myyyyyy day, so it was every man for himself!

[Edited on 18/4/12 by Liam]