kraM
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| posted on 28/12/06 at 12:28 PM |
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Chassis design
I own a classic MK1 Golf and for what it is it is great, just could do with a few things, like rear wheel drive.
I want to build a chassis to support the motor, transmission, suspension, basicly everything, but with the wheel base of the golf. Then cut the floor
pan out of the golf and put the two together.
I intend to use double A arm suspension all round, and maybe a 944 rear gearbox, powered by a rover V8. I also intend on having the engine as far
back as possible, at least so the pulleys are inline with the front axel. (The idea being a fairly standard looking golf with good handling and a
smidge more than standard get up and go, maybe another 200bhp on the 150 under the bonnet)
Any hints and tips on design and my idea please, am I nuts to attempt this?
Cheers for any suggestions
kraM
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MikeR
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| posted on 28/12/06 at 12:46 PM |
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I'd be tempted to revise your engine choice - Rover V8's can make 350hp but its not the cheapest way to that much power.
You'll need to start reading the mid engine section - these guys have covered the sort of problems you'll encounter & their first
suggestion is around a years reading on chassis design / suspension! Ok, none of them have probably done that, but its setting the expectation that
this is a complicated beast.
Good luck 
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garage19
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| posted on 28/12/06 at 01:08 PM |
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The 944 box still has the clutch on the engine up fron so would be no good for what you want.
Why not stick with VAG parts?
Use an Audi transaxle with some thing like a 1.8t engine bolted to it.
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suparuss
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| posted on 28/12/06 at 01:47 PM |
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im thinking the same, you could probably get more power from something smaller and cheaper. and to convert to longitudinal mounted rear wheel drive
you could probably get away minor structural upgrades, as well as putting in a tunnel to accomodate the drive shafts. a welded in aproved roll cage
would add all the stiffness it will ever need. the main strength issue would be torsion along the length of the car due to having the engine torque
going from front to rear which a front wheel drive car is not designed for.
for more specific help try looking for a vw forum or magazines as im sure this will have been done quite a few times before.
[Edited on 28/12/06 by suparuss]
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kraM
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| posted on 28/12/06 at 02:28 PM |
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Thank you all for your thoughts so far.
I knew it was going to be a big undertaking, my golf is a bare metal restoration, hence the bald patch. I had thought of the 1.8t route, but
arn't they expensive to get hold of, because you need all the wiring and dash clocks etc.
I had never thought about the stiffness being a problem, due to using a chassis, I know from a safety point of view the roll cage is a very good idea,
but having worked on a lot of race cars (tin tops, britcar etc) I know getting in and out of them is an art.
Do you reckon an Audi rear axel will handle all the poke, I thought their 4x4 systems were only 4x4 when the front wheels spun?
An idea I had played around with was grafting the MK2 G60 Rallye running gear with a 1.8t lump, but this has been done, and talking to the guy who did
it says it is a massive under taking in a MK1. (steering rack has to move = modded steering colume + bump angle has to be re-adjusted, transmission
tunnel has to be pretty much re-built, the rear of the floor pan has to be re-made, hence the chassis idea)
The only reason for the rover lump was that it sounds nice and I can get hold of one.
(sudden excited thought)
OOOOOOOOOOO, how about a proper 20v lump, with 5 cylinders?!?!
(or an old merc 560 lump?!?!)
Is this why I am almost skint and the dog doesn't reckonise me?
Cheers
kraM
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goodall
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| posted on 28/12/06 at 02:55 PM |
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if you have a proper audi quattro system with the longatudial engine its got a either a torsen centre diff or a lockable open diff in the centre that
system sends power to every wheel all the time but if the engine transversaly mounted it is a haldax cluth system and its requires the front wheels to
spin before power is sent to the rear diff
i'd go with the audi quarrtro system from between 1988 and 1994 so that you get the torsen centre diff and that theres no complex electrics with
the system and mate it to the rover V8
[Edited on 28/12/06 by goodall]
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pathfinder
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| posted on 28/12/06 at 05:26 PM |
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Wasn’t there a chap doing the same thing with a mk1 escort in ppc magazine! Think it was a monthly article but never saw it completed. Would be a
massive undertaking but could be good. I wouldn’t go the rover v8 route either, how about twin bike engines (grasstrack style) or something jap with a
turbo. Dub sport are the chaps to talk to.
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cymtriks
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| posted on 28/12/06 at 06:55 PM |
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Not the RV8
The following was posted by an engine expert who used to work at BL (Rover/Jaguar) and then Jaguar after the sell off.
The RV8 is not light weight or particularly powerful. People just think it is because, when it was first introduced it was when compared to the
alternative massive iron block designs around at the time.
Cheapness and the availability of power mods made it an attractive choice for a long time but TVR had to bore it out to 5 liters before finally
calling time on further use.
Anyway, here's the info.
On PH Marquis Rex said-
These are the true weights of a late disco 4 litre engine, compliant with all the modern emissions and refinement criteria.
Accessory Drive Belt - (1) 0.341kg
Air Cleaner Body 0.977kg
Air Cleaner Element 0.299kg
Air Cleaner Top 0.467kg
Air Flow Meter 0.226kg
Air Hose/Duct - (1) 0.325kg
Alternator 7.196kg
Engine Complete 177.000kg
Engine Management - E.C.U. 0.390kg
Starter Motor 4.060kg
Viscous Coupling 2.942kg
Engine Oil 5.676kg
The above comes to 200 kgs. Now an earlier vehicle will probably NOT have the reduction gear starter motor fitted and so you can expect that to weigh
about 8 kgs, the accessory drive won't be poly belt driven but individually driven So that will weigh quite a bit more. The above also does NOT
include the flywheel, which on the Rover is very very heavy compared to it's contemporaries. So we're already looking at way over 220 Kgs.
The extra capacity over the 3.5 litre will lose some in the crank area, but because the RV8 doesn't have a fully counterweighted crankshaft- not
as much as you might imagine. The block has been reinforced since the early days, but I can't see that adding much more then about 5-6 kgs. So
these silly figures of around 140Kgs are Science Fiction.
Other points of note are the fact that the valve timing does its own thing about about 4000 rpm due to the flex in the pushrods and rocker shaft
location-this has a HUGE effect on top end power, an area where the undervalved Rover V8 struggles already- enlargening the capacity further will just
boost low speed torque with little effect on peak power due to the restrictive nature of the cylinder heads- you’ll end up having to go to specially
made Wildcat heads to get the top end back unless you’re particularly fond of the feel of a “diesel-esque” torque curve. Now don't get me wrong,
the RV8 is a great "working class hero" of an engine- readily available. I TOTALLY understand the emotional reasons behind choosing this
legendary stalwart powerplant, or retaining it for a sense of originality- fair play. But when biased folk start to pitch this motor, on function,
against the Chevy C5 motor or a twin cam Jag, BMW, or Porsche V8s spending thousands upon thousands and seriously believing all the hype,
they're on shaky ground.
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suparuss
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| posted on 28/12/06 at 08:08 PM |
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quote:
Originally posted by goodall
i'd go with the audi quarrtro system from between 1988 and 1994 so that you get the torsen centre diff and that theres no complex electrics with
the system and mate it to the rover V8
[Edited on 28/12/06 by goodall]
The older quattro's where all longidudinally mounted with the front half shaft outputs just to the rear of the engine meaning the whole engine
has to be in front of the front axle line so i doubt it would fit into a golf.
it would have to be modern one which are mostly transverse which would pretty expensive.
mating a modern 1.8t to decent rear wheel drive gearbox seems more straight foreward and probably be ok in the original mk1 chassis with slight
modifications.
when i said a full cage was a good idea it was assuming youd use the v8 which have a lot of torque, may not be necesary with a smaller engine.
[Edited on 28/12/06 by suparuss]
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goodall
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| posted on 28/12/06 at 09:12 PM |
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the A3 and the TT have its east west mounted but all the family saloons and the mpv/suv have it north south and a transaxle in the front and a normal
diff in the rear connected by a split shaft with cv's at the diff and gearbox end and a u joint in the middle maybe its a cv in newer cars.
it you want to keep it simple stick with rwd and a V8 with a ford box you could use the audi system by haveing a small angle in the front drive shafts
and haveing the engine pushed right up to the front cross member jsut like the audi is anyway but by useing a V8 its that cyclinder shorter and the
golf should have just the right amout of room, but its up to your self at the end of the day cause the awd is going to take that bit longer and
won't be the same fun to drive but will be able to do things that little bit faster
[Edited on 28/12/06 by goodall]
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kraM
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| posted on 30/12/06 at 05:21 PM |
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Very true, The thing is, from a tecnicial point of view, Audi is wrong, hanging a huge weight in front of the front wheels, and Porscher is wrong with
all the weight hanging over the rear. Trouble is they have the money to make it work, if I made a car of that style of setup up it would either be
the understeer monster of the 2007 or the ba*tard thing would swap ends at the sniff of a wet cornor!!!
So twin turbo 4x4 moster it is then!!!
No seriously thank you for your suggestions so far, I think next week end will be spent wondering scrapyards looking at various manufactors ideas. I
do like the idea of keeping it a one make car, but have VW ever made a huge power rwd car? The V.A.G hasn't, and if I use the Audi setup, I have
to rip the 'box apart and remove the front wheel drive train.
I suppose I could always make up a subframe and mid-mount a east-west engine and box setup...
Oh the endless thoughts, may have to check the 'lack' of bank balance.
Cheers
kraM
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