What would you chose...
Discussion
A hypothetical (for now) question, which of these seating layouts would you chose (all else being equal)
Normal 2 seater
2 seats front, 1 seat rear (behind passenger)
1 seat front, 2 seats rear/sides (ala McLaren F1)
Brainstorming some ideas for the layout now that I have my ideal drivetrain sort of worked out (this was the most important part as it's doing something different while minimising the amount of custom parts needed)
Normal 2 seater
2 seats front, 1 seat rear (behind passenger)
1 seat front, 2 seats rear/sides (ala McLaren F1)
Brainstorming some ideas for the layout now that I have my ideal drivetrain sort of worked out (this was the most important part as it's doing something different while minimising the amount of custom parts needed)
I spent several months playing around with 3 seater configurations, and came to the conclusion that there is a very good reason McLaren adopted the seating layout and positions they did. Anything else makes the car very, very wide, and the headroom for the passengers very lacking unless you want a virtually slab sided car right up to the roofline.
You can compact the 1+2 layout into a quite remarkably small area if you allow for the fact that the hips may be wide but the ankles generally aren't!
You can compact the 1+2 layout into a quite remarkably small area if you allow for the fact that the hips may be wide but the ankles generally aren't!
Chris71 said:
Personally I'd go for 2 seats and the biggest boot you can accomodate. I rarely need to carry more than one passenger in my 'fun car', but it would be nice to get a bit more use out of it with enough practicality to carry some more gear.
I'm trying to come up with something that is both a fun car and a usable daily, though the luggage space will be dictated by the requirement for wheelbase and any space left in front or behind the engine as I don't want any overhangs.rypt said:
Chris71 said:
Personally I'd go for 2 seats and the biggest boot you can accomodate. I rarely need to carry more than one passenger in my 'fun car', but it would be nice to get a bit more use out of it with enough practicality to carry some more gear.
I'm trying to come up with something that is both a fun car and a usable daily, though the luggage space will be dictated by the requirement for wheelbase and any space left in front or behind the engine as I don't want any overhangs.The plan is for mid engine AWD, right now I have it fully worked out using a longitudinal engine layout, so any luggage space would be behind the engine (in order to get the best weight distribution as gearbox will points forwards) within the wheelbase.
I just can't think of a good way to do a transverse AWD layout, even using custom centre diff casings and chain drives
I just can't think of a good way to do a transverse AWD layout, even using custom centre diff casings and chain drives
rypt said:
The plan is for mid engine AWD, right now I have it fully worked out using a longitudinal engine layout, so any luggage space would be behind the engine (in order to get the best weight distribution as gearbox will points forwards) within the wheelbase.
I just can't think of a good way to do a transverse AWD layout, even using custom centre diff casings and chain drives
Would be interested to hear more about that, it sounds space demanding, and a bit complex too.I just can't think of a good way to do a transverse AWD layout, even using custom centre diff casings and chain drives
You use a normal FR engine and gearbox (longitudinal), then use the centre diff out of the Audi Q7 (can take lots of power and is based on the Torsen T3 unit) - the only problem is the cost of that part
You would need to get a different unit to put inside, as the T3 has a default torque split which will not be reversed. By my reckoning for my idea you want 60 rear, 40 front split at minimum. Torsen should be able to supply a 40/60 unit (remember it is reversed now, so you would need one designed for 60 front, 40 rear).
You then need a couple of differentials that can be flipped in their housing, Nissan 200 units (1 up from the 180s in the Impreza) would work ... though they are a bit large and heavy (but there are plenty of units that can be used, so it is not a problem).
The hardest part is weight distribution (due to the engine being so far back) - meaning that you need to add space behind engine in front of rear wheels to lower the polar moment due to the engine, the gear shift mechanism (as they would be backwards now, though I think by changing the attachment of the throw stick to the shaft relative to the pivot point you can fix it), and sourcing a Q7 centre diff (expensive).
(there may be other sources for the diff, but the Q7 is a separate unit making it much simpler to bolt on)
That is ONE idea.
Another method is to take a FF engine/gearbox (transverse) but mount the engine longitudinally, thus making the stock front diff act as the centre diff. Mount a couple of drive shafts and diffs to this, and you have AWD.
The problems with this are that now you have the shift pattern sideways, which is NOT as easy to fix (you could use a VW DSG box, but it is heavier). Not only that, but the diff in the FWD box would not be ideal for AWD, as you cannot use the T3 with a pre-loaded bias.
The last method is me thinking up of some custom housings and using chain drive with a normal MR setup (also removing the 2nd output and diff in the FWD box), though I've not fully explored this.
The 1st method would work, and would not be THAT hard to sort the issues, but you are looking at a car that is not ideal in length for what it is (though you can go for silly power and stick in a V8 or V6 in there without compromising anything) - then again, that means larger wheels, softer tyres, etc just to put all that power down, making it not the point and squirt machine I want.
The 3rd method shows the best promise for making something unique (I'd use chains over shafts for simplicity), but as I said I have not fully worked it out yet as I spent time working out and sketching out the other two so far.
You would need to get a different unit to put inside, as the T3 has a default torque split which will not be reversed. By my reckoning for my idea you want 60 rear, 40 front split at minimum. Torsen should be able to supply a 40/60 unit (remember it is reversed now, so you would need one designed for 60 front, 40 rear).
You then need a couple of differentials that can be flipped in their housing, Nissan 200 units (1 up from the 180s in the Impreza) would work ... though they are a bit large and heavy (but there are plenty of units that can be used, so it is not a problem).
The hardest part is weight distribution (due to the engine being so far back) - meaning that you need to add space behind engine in front of rear wheels to lower the polar moment due to the engine, the gear shift mechanism (as they would be backwards now, though I think by changing the attachment of the throw stick to the shaft relative to the pivot point you can fix it), and sourcing a Q7 centre diff (expensive
).(there may be other sources for the diff, but the Q7 is a separate unit making it much simpler to bolt on)
That is ONE idea.
Another method is to take a FF engine/gearbox (transverse) but mount the engine longitudinally, thus making the stock front diff act as the centre diff. Mount a couple of drive shafts and diffs to this, and you have AWD.
The problems with this are that now you have the shift pattern sideways, which is NOT as easy to fix (you could use a VW DSG box, but it is heavier). Not only that, but the diff in the FWD box would not be ideal for AWD, as you cannot use the T3 with a pre-loaded bias.
The last method is me thinking up of some custom housings and using chain drive with a normal MR setup (also removing the 2nd output and diff in the FWD box), though I've not fully explored this.
The 1st method would work, and would not be THAT hard to sort the issues, but you are looking at a car that is not ideal in length for what it is (though you can go for silly power and stick in a V8 or V6 in there without compromising anything) - then again, that means larger wheels, softer tyres, etc just to put all that power down, making it not the point and squirt machine I want.
The 3rd method shows the best promise for making something unique (I'd use chains over shafts for simplicity), but as I said I have not fully worked it out yet as I spent time working out and sketching out the other two so far.
rypt said:
The plan is for mid engine AWD, right now I have it fully worked out using a longitudinal engine layout, so any luggage space would be behind the engine (in order to get the best weight distribution as gearbox will points forwards) within the wheelbase.
I just can't think of a good way to do a transverse AWD layout, even using custom centre diff casings and chain drives
I'm being dense here; why would the gearbox point forwards? I would imagine such a layout to have the engine/gearbox in normal orientation, but just at the rear of the car. So luggage would go over the gearbox? (and be warmed by the exhaust). How would you get the drive forwards?I just can't think of a good way to do a transverse AWD layout, even using custom centre diff casings and chain drives
BTW, in another post you say that it would be difficult to fix a sideways gate on the gear box. It would be easy with a cable change. You can change the cross gate and gear select throws at the lever end.
McLaren F1 arrangement. They did it for a reason. Normally, there's only one person in it. You want that weight on the centre line to keep the corner weights balanced. Sitting offset in my Rush, the difference in grip left and right is quite noticeable. If a drivers seat in the centre is a practical option, do it.
Plus it must enhance the driving experience, like you are in a proper race car!
Plus it must enhance the driving experience, like you are in a proper race car!
Davi said:
I spent several months playing around with 3 seater configurations, and came to the conclusion that there is a very good reason McLaren adopted the seating layout and positions they did. Anything else makes the car very, very wide, and the headroom for the passengers very lacking unless you want a virtually slab sided car right up to the roofline.
You can compact the 1+2 layout into a quite remarkably small area if you allow for the fact that the hips may be wide but the ankles generally aren't!
That's another good reason.You can compact the 1+2 layout into a quite remarkably small area if you allow for the fact that the hips may be wide but the ankles generally aren't!
Paul Drawmer said:
rypt said:
The plan is for mid engine AWD, right now I have it fully worked out using a longitudinal engine layout, so any luggage space would be behind the engine (in order to get the best weight distribution as gearbox will points forwards) within the wheelbase.
I just can't think of a good way to do a transverse AWD layout, even using custom centre diff casings and chain drives
I'm being dense here; why would the gearbox point forwards? I would imagine such a layout to have the engine/gearbox in normal orientation, but just at the rear of the car. So luggage would go over the gearbox? (and be warmed by the exhaust). How would you get the drive forwards?I just can't think of a good way to do a transverse AWD layout, even using custom centre diff casings and chain drives
BTW, in another post you say that it would be difficult to fix a sideways gate on the gear box. It would be easy with a cable change. You can change the cross gate and gear select throws at the lever end.
The reason I'm going for the reverse setup is to minimise the length of space needed behind the driver in front of the rear axle.
A normal setup using say an S2000 engine and gearbox would need 51" plus transfer case (as I said Audi Q7 one) + diff - that is 1.5+meters.
If you have the setup the other way round, with the engine behind the gearbox then you only need 30", or 75ish cm plus the diff.
It will mean that the passenger / driver seats are about 10" apart though
The only issue with 1+2 is that with AWD you will have a tunnel running under your seat, you it means you have to sit above it thus giving you a higher up position
Edited by rypt on Wednesday 26th May 19:27
Paul Drawmer said:
So; is the engine behind the rear axle then?
It would be ahead of it, with the driveshaft running next to the engine (hence the use of an I4) or under the engine (if dry sumped V6/8) to the diff with the position of the rear axle being wherever you want to put it to get the best polar moment / weight distributionrypt said:
The only issue with 1+2 is that with AWD you will have a tunnel running under your seat, you it means you have to sit above it thus giving you a higher up position
I missed the bit about it being 4wd. Have to say in that case, forget a 3 seater. I tried that to start with, the third seat ends up unusable no matter where you put it unless one of your 2 friends is 3ft tall, or you want to make the car look like an MPV on roofline, which given your outline I'd believe not. Edited by rypt on Wednesday 26th May 19:27
Admittedly my design was to be kept as low as possible but that fore prop just made things unworkable in supercar guise. (IMO!)
Gassing Station | Kit Cars | Top of Page | What's New | My Stuff