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stock suspensions
scuzzer - 31/8/03 at 09:23 PM

I just finished reading “Chassis Engineering” by Herb Adams. Good book. Can I just throw the engine/transmission/suspension in the back and make it work how it is and duplicate the same suspension up front? I realize I will have to have bigger tires in the rear to make up for an uneven weight distribution, which will shift the instant centers outward if I want to keep the front and rear wheels inline. I could have a negative offset in the rear to keep the driveline the stock length. The disadvantage of all this would be 1) not being able to rotate the tires 2) having to buy different wheels. This set up would decrease the scrub radius in the rear as compared to the front. Another option would be to not have the same track in the front and back. This would eliminate the need for different wheel offset. Another option would be to use the same wheels all around and lose performance for simplicity. I cannot change the tire width difference more than 20mm or so on the same width wheel. Opinions? On an unrelated question, I live in Texas, do I have to have a glass windshield to be legal or can I use Plexiglass?

Rorty - 1/9/03 at 03:40 AM

I'm not really sure what you are saying in the first part of your post, but I do know, scrub radius is not applicable on the rear, unless you're talking about a rear-steering car.
In answer to your windscreen query, I would doubt any public road authority anywhere in the world would permit anything other than safety glass for the forward facing windscreen.

TheGecko - 1/9/03 at 03:59 AM

Can I just throw the engine/transmission/suspension in the back and make it work how it is and duplicate the same suspension up front?
Well that probably dpends what engine/transmission/suspension package it is. Your builder info says 'Mid engine V6" but no further detail.
If the powertrain in question has Macpherson strut suspension then, yes, you probably can 'throw it in the back' by just replacing the steering tie-rods with links to the chassis (this is exactly what Toyota did on the MR-2.

The second question is as to what you mean by "duplicate the same suspension up front"? If you mean use another set of the same front suspension as the powertrain donor (eg Macpherson struts) than maybe/maybe not. A strut front end is pretty tall for a sports car. I think you're better off trying to build something like the Locost book fron suspension, using whatever uprights you can get with the right stud pattern.

To put this in perspective, here's a quick description of my mid-engine build:



I realize I will have to have bigger tires in the rear to make up for an uneven weight distribution
Says who? The X1/9 and the Mk1 MR2 both had the same size wheels and tyres all round without major ill effects and I'll be doing the same. It simplifies things and makes it straightforward to carry a spare.

On an unrelated question, I live in Texas, do I have to have a glass windshield to be legal or can I use Plexiglass?
This seems to be one of those things that vary the world over. Generally speaking though, plastics are not permitted for windscreens, as much because of their poor resistance to scratching and crazing as anything else. In Australia, if the driver looks through it rather than over it (as in a wind deflector) than it has to be made of glass.

Hope some of this is helpful,

Dominic

sgraber - 2/9/03 at 12:36 AM

Here is a rendering of the K1 Attack that uses a Honda V6 in mid-engine config.It uses the stock Honda front suspension in the back. That's what you were asking right?



Your front suspension could be as simple as buying a Fiero tubular subframe assembly and bolting it onto your chassis or it can be as complex as designing/building everything yourself. The only limitations are time and money!

Steve

kb58 - 2/9/03 at 02:53 AM

I see you visited the "Temple of K1." I've never seen a group of people so brainwa.... I mean "enamoured" with a kit car. I pretty much got tared and feathered after suggesting they be very very careful when dealing with the company (they're in the former Czech republic!) and be careful regarding emissions.

Geez you'd have thought I'd have gone into Iraq and started yelling bad things about the Koran.

One thing about the K1, it's set up for the 4-cylinder, not the V6.

[Edited on 2/9/03 by kb58]

scuzzer - 6/9/03 at 08:12 PM

Thanks, your right. The scrub radius isn't applicable in the rear. I have been reading like crazy and I guess I just got ahead of myself. The donor is a 89-95 Taurus SHO V6. You can get the specs on the 'engines' post. I've been thinking hard and at this point I have pretty much decided to design my own front suspension and maybe have struts in the back like the Attack. I have no idea what uprights would be best for the front. It will be up in the air for a long time before it's final though. Thanks for your input.