Bump Steer

How to upgrade your Austin...and further......
Big Daddy
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Re: Bump Steer

Post by Big Daddy »

gazza82 wrote:It will need some Evo2 arches ... ;-)
Unfortunately Dave thinks Evo2 arches are "grotesque"... :!:

gazza82 wrote:I quite fancied putting an Alfa 75 TS runing gear with rear transaxle under one ... But my imagination is better than my engineering skills. :-(
Alfa powertrains are good especially with that transaxle. Porsche 4-cylinder powertrain has promise as well.

I like the concept of a shortened MX5 platform (aka floorpan) with A35 "top hat" grafted on. Dave's 200+ hp should be readily available from the turbo variant... :thumbs:
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gazza82
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Re: Bump Steer

Post by gazza82 »

We had a 2.0 TS 75 for over ten years ... quirky little beast with fantastic handling .. and as it had a LSD was the envy of many of my work colleagues when I just got in and casually drove home in the snow .. and they struggled to get their souped-up FWDs out of the car park! I didn't want to get rid of it but 100K was beginning to take it's toll and the Italian electrics drove me nuts!
"If you're driving on the edge ... you're leaving too much room!"

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Cars: "Project 757" '59 A35 2-door bought in 1971 & Subaru BRZ SE LUX Auto plus "family fleet": Alfa MiTo, Peugeot 206, (Ex '98 Alfa Romeo 156 2.0 TS)
Dave Clark
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Re: Bump Steer

Post by Dave Clark »

Re four wheel drive - some Fords seem to manage quite well ?

A35 atop MX5 has already been done but track width meant somewhat grotesque arches.(both front and rear)
Big Daddy
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Re: Bump Steer

Post by Big Daddy »

Dave Clark wrote:Re four wheel drive - some Fords seem to manage quite well ?
Ford Ranger truck is fairly good at traversing ploughed fields... :thumbs:

But seriously, for good dynamics fixed torque distribution has limitations. Really need fully active 4wd as demonstrated by Mitsubishi and Nissan. Successful configuring and calibrating an active system for an A35 would be a huge challenge.
Dave Clark wrote:A35 atop MX5 has already been done but track width meant somewhat grotesque arches.(both front and rear)
... :rol:
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Big Daddy
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Re: Bump Steer

Post by Big Daddy »

gazza82 wrote:.. and as it had a LSD was the envy of many of my work colleagues when I just got in and casually drove home in the snow .. and they struggled to get their souped-up FWDs out of the car park!
:mrgreen: ... :thumbs:
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fsmlittler
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Re: Bump Steer

Post by fsmlittler »

Ok so we measured toe changes at various ride heights up and down from our standard resting ride height and discovered the following:-
At one inch compressed or one inch extended there was little movement but by two inches either way we had significant toe in. I had assumed that as the suspension travelled it would revert from toe in to toe out. Wrong.
We then fitted the A40 steering rods and adjusted them to extend the length which reduced the compressed deflection significantly but had little effect on the extended deflection. We will continue to exeperiment with trial and error to see how far we can reduce bump steer.
The initial bump steer on compression caused enough toe in to see the wheel turn inwards just by observing it. No wonder the car felt twitchy under heavy breaking.
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Countryboy
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Re: Bump Steer

Post by Countryboy »

Rest Home for rusty vehicles
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