FWD Gearbox in the rear

I will start a project thread once things are underway.

I need to find a book on suspension maths, that is the main issue I'm going to have at the moment.

MrLOL said:
i think 400kg seems more likely. The atom weighs 450kg in base spec, so not sure how you can make a 150kg weight saving on that unless your building a slightly oversized go kart !
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This pretty much is just an oversized go-cart ;)
 
Im a little lost here to.Im all for the A series but not if I had a choice I would have gone the Honda route wooot tbh.

d16a9 = 130bhp
b series well 160bhp :) nice light engine revvvvvvssssssssss well to :)
 
MikeHiow said:
I need to find a book on suspension maths, that is the main issue I'm going to have at the moment.
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Staniforth was a suspension designer and has a whole book on the subject...it's not on my bookcase so I've forgotten what it's called. I'll dig it out, but check out Staniforth and Des Hamill. Staniforth is really a string and ruler guy and you won't get a better start on a project but to refine it you should use Hamill as he's more up to date. Best I can do over the weekend is scan the Suspension and Geo chapter from Race&Rally which is a insight into the rear-engined suspension development plus the fundamentals and the formula/maths to use, if you want it.
 
D.Roberts said:
Im a little lost here to.Im all for the A series but not if I had a choice I would have gone the Honda route wooot tbh.

d16a9 = 130bhp
b series well 160bhp :) nice light engine revvvvvvssssssssss well to :)
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This cars primary use will be auto testing, where yes, a high revving engine would be useful, but the powerband of a b16 will be not so useful.

A-Series is cheaper, but more importantly stupidly simple - no complicated ecus etc. to mess around with (although, something a little more advanced may come later, once everything else has been perfected), and for less than £1k will make 120bhp and rev to nearly 8k ;)

Fett said:
Staniforth was a suspension designer and has a whole book on the subject...it's not on my bookcase so I've forgotten what it's called. I'll dig it out, but check out Staniforth and Des Hamill. Staniforth is really a string and ruler guy and you won't get a better start on a project but to refine it you should use Hamill as he's more up to date. Best I can do over the weekend is scan the Suspension and Geo chapter from Race&Rally which is a insight into the rear-engined suspension development plus the fundamentals and the formula/maths to use, if you want it.
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I'd really appreciate that, thanks.
 
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Dogbreath said:
:confused:

In the mini the gearchange comes out of the back of the gearbox, pointing directly toward the gear lever. When you take the engine out of a FWD car to fit to the rear of something you don't turn it around (unless you want to go backwards very quickly), so in this case you end up with the gearchange exiting the box from the rear of the car. Since a gear lever mounted 3 feet behind your car is of limited usefulness, a linkage to route the remote change back under the engine and into the cabin is quite desirable.

I don't know why they used an A series, but it has significant advantages in terms of packaging to the modern solution of a transaxle on the end of an engine, so maybe space was limited?
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He said 'the gears will be in reverse'.

That means in my mind that they've spun the whole thing round so the gearchange lever is pointing forwards instead of backwards out the back of the car (if it was the same way round).

Sorry. I'm smelling fish or something bad.
 
MikeHiow said:
This cars primary use will be auto testing, where yes, a high revving engine would be useful, but the powerband of a b16 will be not so useful.

A-Series is cheaper, but more importantly stupidly simple - no complicated ecus etc. to mess around with (although, something a little more advanced may come later, once everything else has been perfected), and for less than £1k will make 120bhp and rev to nearly 8k ;)
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How would the B16 power band not be useful? If racing you will be revving high, also while people **** off the torque of Honda engines they really aren't that bad, more than the A series will make.

B16a2 = Less than £1k? Check, Will make 120bhp? Try 160bhp stock, rev to 8k? 8500 rpm isn't a problem.
 
Do you even know what auto testing is? Having an engine that doesn't do anything under ~5500RPM is pretty ****ing useless.

You also seem to have missed my points about simplicity as well as weight - it is entirely possible to overpower a car that weighs in the region of 300kg, especially for its given purpose.

Also, a tuned A series will easily make 120lbft, I make that 10 more than a b16a2.
 
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What is the gearing like on the A series though... isnt it a iron block aswell?

Whats the spread of that single peak figure? Lol torque coming into discussion on a 300kg car!

That said a D16 could be a nice one cheaper and lighter and enough grunt with its 90mm stroke.

Anyway get some pics up!
 
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Nick1881 said:
How would the B16 power band not be useful?
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There is a GTM coupe (mid engined kit car based on mini components) with a B16 engine fitted that I see on the local Tarmac rallies, and considering it must have an impressive power/weight it really isn't as competitive as you'd expect. On a very tight, twisty stage it's very difficult to keep the RPM up all the time. On autotest it would be even more difficult.
 
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Dogbreath said:
There is a GTM coupe (mid engined kit car based on mini components) with a B16 engine fitted that I see on the local Tarmac rallies, and considering it must have an impressive power/weight it really isn't as competitive as you'd expect. On a very tight, twisty stage it's very difficult to keep the RPM up all the time. On autotest it would be even more difficult.
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We're comparing it to an A series though, come on, there will be more torque all over the place, way more at high rpm. I find it totally bizarre to say a high rev engine would be good then dismiss the B series because of the power band. It has the best power band of a high rev engine. Drive a big cammed engine without the low speed lobes and then you will know what gutless low rpm is all about! Want to run strong at high revs then you need big lumpy cams, no way around it.
 
I LOVE how you ask for some simple advise and the thread just spiralled into how you SHOULD have done it with little real advice. Everyones a ****ing OCUK expert eh? :rolleyes: ;)

Ant :cool:
 
Clarkey said:
Want to run strong at high revs then you need big lumpy cams, no way around it.
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A supercharger would be one way around it...

You simply don't need massively high revving engines for something like autotesting, you need something that will pull strongly from virtualy nothing. You ceratinly don't want something where you get a big increase in torque past a certain rpm. I'd be willing to bet the number of competitive B series engined cars in autotest is absolutely miniscule compared to minis (and mini based specials) and Lotus 7 style cars.

People have also convienitently overlooked that there may be some very compelling reasons why an A series was chosen, a conventional FWD powertrain may simply not fit as they are all very significantly wider than a mini powtrain.
 
We went and had a proper look over it today, got a couple of pictures, and found out a bit more information about it.

The actual chassis was originally built by a local garage, to the original owner's design/specification, it then went to GKN to have the appropriate gussets etc. added by engineers specialising in stress testing.

Most of the bits are sourced either from a Mini or a MK1 Fiesta, with the suspension designed around Jaguar items apparently, a little bit of research will be involved there.

In terms of what needs doing, it really needs stripping down, cleaning up and rebuilding, a new floor, a wiring loom made up, new dash panel, a seat fitting and a few other small, trivial bits. The brake lines need running, and there are Cooper S discs and calipers amongst the assorted spares that have been collected for this car. It'll also need new suspension and all the geometry setting up - both front and rear is fully adjustable in terms of geometry.

The engine in there is an early 1275 unit, whether it'll ever run or not though is a different story, not that dropping A new engine in would be too much of a problem, the rear subframe unbolts and rolls out for easy access.

Overall, there isn't anything too difficult, nor is there anything particularly expensive. This will be completed.

Pictures are lacking somewhat, as we were more concerned about getting a game plan together:
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Front suspension uses mini parts all upside down, i.e. upper suspension arm is now on the bottom and vice versa. That is a bit concerning as the suspension forces will now be trying to pull the bottom (previously top) ball joint apart. In the original location the ball joint is pushed together by the weight of the car. It's not unknown for ball joints (in general rather that mini specifically) to fail when not used as intended so you might want to seek advice on this.

I can't see rear suspension, but would be surprised if they didn't at least use the mini/metro uprights. Not too keen on the rather bent bolts on the rear upper damper mounts. Pedal box is mini or metro as well. Rear subframe appears to be a Metro front subframe, and engine looks like a standard 1275 A+ series, so around 62bhp in standard form.

I foresee many hours being spent with an angle grinder and wire wheel in your near future!
 
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Yep, interesting point on the bottom ball joint, however the original builder was no stranger to stuff like this, although I will take heed in your advice and keep an eye on it.

The bent bolts are due to temporary solid bars in place of the shocker, which was used as a temporary measure to setup height etc, so those bolts have been supporting the weight of the rear end for around 15 years - they will of course be replaced when the intended shocks have been sourced.

The rear subframe is in fact a Mini front subframe, you are correct, and yes, the engine is an early 1275.

You are also correct about the hours with an angle grinder and wire wheel, that is the first task after stripping everything down.
 
I seem to recall they did build a Mini Moke with twin A-series engines and may have the kind of linkage you require that went to the rear engine. Other cars to look at would be the Mini Marcos as that had a mid A-series engine.

Quite who would still have these parts is another matter all together.
 
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