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Dimensions and design for tall guy
geoffreyh - 5/6/06 at 03:29 PM

Hi everybody,

I'm having some troubles defining the dimensions of my mid-engined design.
I'm 6'8" or 203cm and have quite long legs. You probably already see where I'm going.
When I calculated the space I had between the wheel caps I had only 1 meter. This isn't enough to get the feet space which is necessary for driver and passenger if we look at the body width as well. So if I start the driver compartiment right behind the wheels and calculate the necessary space the back of my head woud be at 260cm from the front. If I really want the get a well equilibrated car weight the car would be longer then 450cm.
Another option would be to choose for the McLaren F1 seat positions.
This would give the possibility to start the driver compartment between the wheels.

What is your opinion about that.

Geoff

theconrodkid - 5/6/06 at 03:58 PM

have you looked at mcsorley plans? (available on this site for free)he made them for wider/higher etc,just add a few inches here and there till it looks/fits right

geoffreyh - 5/6/06 at 04:04 PM

Thank you for the information but isn't this a locost design with front engine?

Geoff

theconrodkid - 5/6/06 at 05:53 PM

note to self...read the post before replying
imho the principle is still the same tho

RazMan - 5/6/06 at 08:33 PM

quote:
Originally posted by geoffreyh
Another option would be to choose for the McLaren F1 seat positions.
This would give the possibility to start the driver compartment between the wheels.


You might want to have a closer look at my Aeon GT - 3 seater as standard (I converted to 2 seats though) Bags of room for a tall driver, although you will have to adopt a 'laid back' driving position with a custom seat. I found that Ultima seats were perfect but hard to find.

If you discuss your requirements with John at Aeon he can make adjustments to the chassis as required.

Link

[Edited on 7-6-06 by RazMan]

sgraber - 6/6/06 at 11:03 PM

I am 6-3 and when the seat of my la bala is in the furthest back position, I can't touch the pedals. My wheelbase is 98".

What I am getting at is that it's definitely possible to make a chassis to fit a tall person such as yourself.

I was amazed that of the current crop of little sportscars, Elise, Solstice, Sky, I don't fit comfortably in any of them...

I really like the idea of the 3 seater. Razman, is the driver position in the center? Got photos?

geoffreyh - 7/6/06 at 06:28 AM

Thank you Steve but what about the weight distribution of your car? I want to make a real mid-engined car. An option would be a design like yours if the first idea doesn't work.

Nice to see your molds are ready and you had some family time. How many bodies do you think you will be able to get from this molds? It's known that molds are deteriorating after a couple of bodies.

Geoff

TheGecko - 7/6/06 at 06:42 AM

quote:
but what about the weight distribution of your car? I want to make a real mid-engined car.
Careful Geoff, that's the sort of remark that might start a fight around here

Seriously though, I'm always a little bemused when someone states that a transverse drivetrain isn't a "real" mid-engine. In what way? There's actually more of the drivetrain in front of the axle line than there is when you have 30-40kg of inline gearbox hanging behind the axle line!

Or am I mis-understanding your remark?


Dominic
(who believes that his transverse 20-valve drivetrain is very much a mid-engine)

RazMan - 7/6/06 at 07:09 AM

quote:
Originally posted by sgraber
I really like the idea of the 3 seater. Razman, is the driver position in the center? Got photos?


As my car is a two seater version with a conventional layout, it is best to check out the Aeon website to get an idea of how it works with three seats. Suffice to say that there is bags of room in a central driving position with two rather 'snug' passenger seats placed a little further back.

Aeon Sportscars

[Edited on 7-6-06 by RazMan]

sgraber - 7/6/06 at 04:11 PM

quote:
Originally posted by geoffreyh
Thank you Steve but what about the weight distribution of your car? I want to make a real mid-engined car. An option would be a design like yours if the first idea doesn't work.

Nice to see your molds are ready and you had some family time. How many bodies do you think you will be able to get from this molds? It's known that molds are deteriorating after a couple of bodies.

Geoff


Good questions Geoff! Just before I started the bodywork I weighed the car on 4 350Lb bathroom scales. (and this is before adjusting the suspension to balance the weight properly)

* Right rear - #344
* left rear - #326
* right front - #236
* left front - #216
* Rear weight total - #670
* Front weight total - #452
* Complete car total - #1,122
* 59% rear : 41% front

The hips of the driver are directly at the centerpoint between front and rear wheels, and the center of gravity (the see-saw balance point) front to rear is about 6" behind that. Or basically in-line with the drivers head. I think that this is an ideal balance due to the fact that under acceleration we want more weight over the rear and during braking, there will be weight transfer to the front wheels.

My 'glass man believes we should be able to get over 75 bodies from these moulds. If they are treated nicely I think that's doable.

A transverse middy is still a real middy. If you simply meant an inline middy I will give you the leeway. Otherwise I'll send some swarthy New York Italians over to "convince" you otherwise. (just joking) By the way, there is less driveline loss in a transverse layout as well as a significant gain in cockpit space. The only drawbacks I can think of is that with a transverse you don't have that lovely racecar "look" of the inline (poser value) and the mass is spread further outboard towards the edge of the chassis. But unless you are making a single seater I believe the benefits of transverse layout outweigh those minor drawbacks.

Also, you mentioned placing the drivers legs between the front wheels. I believe that there are some good reasons not to do this. The problem arises when there is an impact at the front wheel that breaks the a-arm and projects it through the side of the cockpit. It basically becomes a lance that will penetrate... your legs or ankles or feet... This is not just theory, it does happen and it's a very good reason to keep your feet behind the a-arms.

RazMan, I pored over the Aeon site looking for a decent photo of the rear seats and there were none. Can you tell me, are the rear seats custom built to a smaller size?

geoffreyh - 7/6/06 at 06:44 PM

Thank for all this information

Just to please everybody: An in-line mid engined car has his engine more in the middle than a transverse but they have both their engine between their axles. ;-)

About the feet between the wheels:
It's not really between the wheels but by having a center driving position you can put your pedal box more to the front.

Steve or Andy (GTTMan) I would like to know what the space is between the two most inside positions of your tyres. With 255 front tyres and a car which is about 190 wide I would have something like 100 over. Not a lot to get two seats in ;-)
Especially if you are 203 and weights about 105kg and your shoulders are about 55 wide.

Steve your front is also converting to front or not? By using this technique and reinforcing the panels I will create a safer front.

Is 470 too long for a car?

What do you think about all my comments?

Geoff

gttman - 7/6/06 at 08:29 PM

I have kept my feet behind the front wishbones but beside the wheels..... I spent many hours mocking up the driving possition.

I think you will have issues if you put your feet in front of the wheel CL as then you may need front end crush zones to become road legal.

If I used Ultima seats I think I could get a 6.8ft man in mine comfortably.... my wheelbase is 2610 and the car will be around 4200 long.

[Edited on 7/6/06 by gttman]

gttman - 7/6/06 at 08:29 PM

as a comparison a finished Ultima GTR without fuel is 63% rear and 37% front.

RazMan - 7/6/06 at 09:09 PM

quote:
Originally posted by sgraber
RazMan, I pored over the Aeon site looking for a decent photo of the rear seats and there were none. Can you tell me, are the rear seats custom built to a smaller size?


I have just trawled through all my pics of their three seater demo car and I can't find a single shot showing the seats

The central seat is fairly conventional - I think a Westfield seat was used in the demo car but the two passenger seats need to be fairly narrow to fit in the available space. I know that they are designing their own seats based on the Elise design. A lot depends on the size of your passengers. In my case, both my wife and myself are over 6 feet tall so I decided to convert to two seats, allowing a little more side room, even with a central tunnel (for rad pipes, loom, gear linkage etc) but due to the lack of headroom I couldn't use conventional seats and ended up with Ultima seats which are very laid back but comfortable.

[Edited on 7-6-06 by RazMan]

geoffreyh - 8/6/06 at 12:56 PM

Gttman,

Is it possible to get to me with some dimensions? Maybe I can prepare a spreadsheet with some dimensions I would like. You have my mail address or you can PM me if this would be ok.

How is progress by the way?

Geoff

gttman - 8/6/06 at 08:08 PM

Height 1130
Width r 2000
Width f 1890
Wheelbase 2610
Length 4200
G clearance 110
(front splitter, side splitters and under the seats).

As a comparison an Ultima CAN be made to fit a 6ft 7 man (I have a freind who is and has one). and my car is 90mm higher and a 100mm longer wheelbase and over 100mm wider.
Another point is that I have gone for quite a short wheelbase for the width of my car you may want something slightly longer (if you kept the same width).

Not sure how usefull my dimensions will be to you, but if you package it correctly you can definatelly fit into a car the same size.

As a point Razman is a tall guy and he has a car even smaller than an Ultima and fits now that we got him some seats that suit the package.

I have a spreadsheet of dimension comparisons for mid engined supercars that I made to answer my own questions that I will send across.

chriscook - 8/6/06 at 09:21 PM

I _think_ the very first Aeon had Fisher Fury seats in the sides or they were certainly talking about using them at some point. I may have only had the central seat in it when I drove it.

russbost - 12/6/06 at 09:39 PM

Seats certainly do make a big difference, also so does chassis height, adding a couple of inches to the height of the driving compartment can make a massive difference to how much room you have for your legs. If I can get 2 seats (with room for people up to around 6'4" seated one behind the other in between a wheelbase (from memory) of 293cm it can't be that hard with only one row of seats. I would say don't worry much about the weight distribution, mine is around 400kg rear axle, 220kg front (again from memory)& the handling is superb as is the ability to put the power on the ground.