Stiffen the rear, reduce understeer?

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Blaze
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Stiffen the rear, reduce understeer?

Post by Blaze »

Hi all,
I read from somewhere, most FWD suffer understeer. One of many ways to reduce this is to stiffen the back of the car. What do you guys think? I've got all this braces came with the car and it must have been done up in Japan. And I havent seen any fto with this stuff. Are they any useful on track? coz i 've never bring her there.
What are other things that people do to reduce the understeer, besides: stiffenning/lowering the suspension, set neg chamber? Ofcourse with a decent set of tyre?

Check these out:
behind the rear seat, when the seat is taken off:
Image

in the cabin:
Image

without cross bars:
Image

with cross bars:
Image

Image

Image

Image
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MADFTO
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Post by MADFTO »

Looks like you've got roll cage for the rear of the car there, that ties into your strut tower brace.

Most of that looks like just strengthening/stiffening of the chassis, it might be remants of a full roll cage . . .

Nice =)
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RichardH
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Post by RichardH »

> What are other things that people do to reduce the understeer

Mine is set up pretty nicely, with:

- Front and rear upper strut braces.
- "Extra castor" bushes on front.
- Camber bolts.
- Good shocks.

With a set of Toyo Trampio R1-R for comp driving, it's very nice indeed.

- Rich
ruchi
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Post by ruchi »

That's some serious sh*t they've done!

FWD cars have an inherent tendancy to understeer while RWD cars have an inherent tendancy to oversteer. This is due mainly to which wheels are putting down the power and most likely to "slip" and loose traction. Having said that, in reality the "inherent" tendancies mean jack-sh*t as virtually all cars are setup and designed to understeer (even RWD) as this is considered much safer than cars which oversteer.

Asking whether stiffening your rear with reduce understeer is a bit like asking if I do "X" mod will I get more power? What it comes down to is the overall setup of the vehicle. Depending upon the existing setup, stiffening the rear may lead to more understeer and likewise doing "X" mod may reduce power.

Remember, having understeer is not necessarily a bad thing.

If you want to lessen the understeer, my first question would be "why?", what is it that you want to do with the car?
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Theremin
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Post by Theremin »

God help any person who runs into the back of your car!!!

I wonder how much all that stuff weighs??
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GPXXX
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Post by GPXXX »

that is one of the most elaborate half-roll cages i've ever seen LoL... the rear chassis must be stiff as hell, and i wonder how it actually got through the compliance/ADR...
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mrdj1234
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Post by mrdj1234 »

might have got past ADR cos it looks bolt on....

that's some serious hardware....

where it attatches, looks like it's more to prevent roll and flex in the body itself than just as an improvement. I've seen drifters do that to their cars to help make them skitter better.... although I can't think why that would be needed in the FTO....

nice place to keep the battery too .... that and the sheer mass of bracing probably have more effect on the handling than anything else...
TimmyD
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Post by TimmyD »

so if someone hit the back of him... would that just screw up the whole back of his car?
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mrdj1234
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Post by mrdj1234 »

just another quickie - if you're going to keep the battery in the boot... get a battery box - they're plastic and pretty much unbreakable - and they stop acid spilling into your boot - doesn't look like that battery has a lot of lateral support


and final thought... how do you get to the spare wheel?
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smorison
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Post by smorison »

mrdj1234 wrote: they stop acid spilling into your boot - doesn't look like that battery has a lot of lateral support

mmmm battery acid.... you should see what that does to a Unifilter pod :P
TimmyD
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Post by TimmyD »

smorison wrote:
mrdj1234 wrote: they stop acid spilling into your boot - doesn't look like that battery has a lot of lateral support

mmmm battery acid.... you should see what that does to a Unifilter pod :P
LMAO!!
And its collapsable (i think) so just take apart some of it and take out the sh*tty little tire and use it :/

Tim
Blaze
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Post by Blaze »

ruchi wrote:That's some serious sh*t they've done!
I believe there must be some purpose behind it. At least it doesnt look like a quick job to do it. And you r rite, it's all depends on the whole set up.
Theremin wrote:God help any person who runs into the back of your car!!!
I wonder how much all that stuff weighs??
Bad luck who hits me. Other than the rear end strut brace, they are all aluminium box section. Pretty light, the Al is less than 2 kgs in total.

The batt is maintenance free, so no acid spills out. It's little bit bigger than previous one, so I cant fit the bracket which was used before. That's why I strap it.
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