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GT40 Tech - Exterior, Interior, AC, & Trim All that other stuff not in categories above.

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Old 27th October 2005, 04:48 PM   #1
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MK II front clips

A question. On the 1966 and later MK IIs the front fenders were raised to prevent the tyres from wearing through the fibreglass. I had always assumed this was merely because the MK IIs ran wider wheels that must have fouled the inner guards. However, MK Is that raced after 1966 also ran the wider wheels but retained the lower profile (more attractive) front guards. Some of the MK Vs (Safir cars) produced later had MK II rear clips but also had the lower profile MK I front clips. Why did the font wheels of the racing MK IIs foul the guards? Was the suspension more compliant, or was there another reason (ride height maybe, or perhaps larger diameter tyres)? Anyone have a definitive answer?

Cheers, Brian
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Old 28th October 2005, 03:10 AM   #2
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Re: MK II front clips

I would guess that the high banked turns, like Daytona, and down force would make the tyres rub the body. ??
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Old 28th October 2005, 03:48 AM   #3
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Re: MK II front clips

Brian,
I would think that guard clearance on all the original cars would be provided to cope with full bump under maximum heavy braking. I would think all the cars would be set up under braking for the suspension to bottom out just before the front of the car touched the ground and the wheel touched the guard ( I may be completely wrong with this assumption, if so Iím sure someone will correct me) thus the differences in tyre diameter would determine the different heights of the guards. From what I can remember reading, the American cars always ran larger diameter tyres front and rear than the English ones did and I think this will be the sole reason for the different front clips. I think from memory front tyre diameters were about 25 Ĺ and 23 Ĺ inches respectively, hence the difference. Although related I donít think either ride height or suspension stiffness or banked turns would be the determining factors only wheel clearance under braking. Someone who is privy to the historical reason for the different clips can now shoot my theories down!

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Old 28th October 2005, 05:38 AM   #4
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Re: MK II front clips

I would have thought that the effects of weight transfer under cornering etc and downforce created at max speed would be the first place to look at when setting ride height and suspension stiffness/travel etc. not the load under braking. If the car hits the stops when braking that wouldnt be as detrimental as having the car riding on the stops through a banked turn etc.

If the suspension is thus setup correctly, then the tyres wouldn't rub under braking anyway. I imagine that the main concern in the braking dept is the split front/rear. Weight transfer to the front under braking could be dialed in/out by adjusting the rear dampers.

Not that I have any experience of this in the real world. Just a fascination for the theory of setup. [img]/ubbthreads/images/graemlins/smile.gif[/img]
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Old 28th October 2005, 05:42 AM   #5
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Re: MK II front clips

The wheels were wearing through the front fenders on the oval circuits so the front clip was changed to accomodate more clearance
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Old 29th October 2005, 01:52 PM   #6
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Re: MK II front clips

Ah yes, that strange American institution where you only turn left and don't have to slow down.... I think the Mk1 bodies would have been originally designed to provide a minimum wheel clearance throughout the full range of available suspension travel. Fitting larger diameter tyres would compromise that. It's amazing how when you change one thing there is a flow on effect in other areas. Change the tyres and you have to change the body, it increases the ride height so if you adjust that out the suspension angles and travel change. I bet the larger bulge to accomodate the taller tyres also introduces a reverse wing effect causing less aerodynamic downforce and so it goes on....

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Old 30th October 2005, 04:58 PM   #7
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Re: MK II front clips

Thanks for the replies everyone.
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