smart51
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| posted on 16/7/09 at 12:19 PM |
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odd handling
My new baby is a Suzuki cappuccino. I like it. It is meant to handle well courtesy of its dual wishbone all round suspension and rear lower multi
link setup. At 60 or so the steering is very light and the whole car feels a bit floaty. There's no play in the steering and tiny movements of
the wheel give small changes in direction, which is good. More substantial turns in the wheel make the car roll very quickly and once the car
settles, the steering is quite heavy and the car corners positively.
What is the likely cause of this? Geometry? Suspension? The car has ARBs front and rear and I notice the front has new drop links.
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MikeRJ
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| posted on 16/7/09 at 12:26 PM |
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Tired dampers? Does it have the OEM wheels fitted?
I like the little Cappuccinos, but they seem to have inherited 70's Alfa corrosion protection, i.e. none, so get the waxoyl out whilst
it's still in one bit!
[Edited on 16/7/09 by MikeRJ]
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nick205
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| posted on 16/7/09 at 12:30 PM |
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Probably teaching you to suck eggs, but have you checked and experimented with tyre pressures?
Other than that I'd look at the dampers and make sure there's nothing amiss.
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smart51
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| posted on 16/7/09 at 12:40 PM |
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quote:
Originally posted by MikeRJ
Tired dampers? Does it have the OEM wheels fitted?
I like the little Cappuccinos, but they seem to have inherited 70's Alfa corrosion protection, i.e. none, so get the waxoyl out whilst
it's still in one bit!
[Edited on 16/7/09 by MikeRJ]
You're right about corrosion protection. I deliberately went for a clean one - a rare thing. I've already waxoyled one bit that is prone
to collecting mud and rotting. The rest will be done over the next month or two as I get time to remove parts for access.
It has and will keep the stock wheels as they're only 4.7kg each! How do I check the dampers? I've never had to do this before.
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speedyxjs
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| posted on 16/7/09 at 01:05 PM |
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I have been experienceing similar symptons with my jag. Its going in this afternoon to have the rear end looked at. I suspect rear shocks but will
post back tomorrow when i find out 
How long can i resist the temptation to drop a V8 in?
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britishtrident
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| posted on 16/7/09 at 01:05 PM |
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If it roll excessively and nothing is obviously broken in the suspension then thats the way it was designed.
Could be the dampers are a bit soft
Dampers will not affect the amount roll when turning in a constant radius, but they do alter the rate at which the car rolls after a steering
input.
Re corrosion pat attening to rust proofing the front suspension mounting points --- they collect stagnant water.
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Mr Whippy
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| posted on 16/7/09 at 01:23 PM |
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I had a fiat cinquecento and tbh that sounds just like the handling of that car. Basically their too short for decent high speed handling and always
feel nervous.
[Edited on 16/7/09 by Mr Whippy]
Fame is when your old car is plastered all over the internet
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smart51
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| posted on 16/7/09 at 01:31 PM |
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quote:
Originally posted by Mr Whippy
I had a fiat cinquecento and tbh that sounds just like the handling of that car. Basically their too short and tall for decent high speed handling and
always feel nervous.
At 1185mm, it isn't that tall really. Comparing the track to wheel base to height ratio, it is an 85% scale model of a real car. It's
even 85% the weight of a small car. Shouldn't the stability be about the same because of the proportions or doesn't it work like that?
[Edited on 16-7-2009 by smart51]
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Mr Whippy
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| posted on 16/7/09 at 01:47 PM |
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I find that is more the length of the car that makes it more stable at high speed, never had a small one that didn’t twitch, missy’s old Corsa (now
finally scrapped & replaced with an nice Almera) was quite scary at 70mph and my Fiesta felt like it was going to flip over when I got it up to
90mph. What you have is a county road corner blaster rather than a motorway cruiser.
One way I suppose to think of it is a pendulum. A short one moves back and forth quite quickly and the longer it becomes the slower it sways. This is
why large cars with long over hangs past the wheel like boots tend to make the smoothest cruisers as their extra length slows down the swaying making
them less twitchy. Really doesn’t matter if the scale is the same as a short pendulum will always be faster, so no you can’t just scale it up and
expect the car to be the same.
[Edited on 16/7/09 by Mr Whippy]
Fame is when your old car is plastered all over the internet
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alistairolsen
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| posted on 16/7/09 at 02:08 PM |
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it will make it twitchy and require more rapid steering inputs and hence be tiring on the motorway, but it would handle well and grip well at speed
and the floaty feeling is definately curable and not an incurable symptom of the vehicle length alone.
My corsa was excellent to drive, but then it was dropped 40mm with a quickrack, proper dampers, brand new bushes, joints and topmounts...
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owelly
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| posted on 16/7/09 at 03:46 PM |
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Have you checked the tracking? If it had too much toe in it would feel as though you were oversteering. Toe-out would feel a bit vague in a straight
line with you having to exagerate the steering to make it play properly.
http://www.ppcmag.co.uk
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Mark Allanson
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| posted on 16/7/09 at 06:46 PM |
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quote:
Originally posted by Mr Whippy
I had a fiat cinquecento and tbh that sounds just like the handling of that car. Basically their too short for decent high speed handling and always
feel nervous.
[Edited on 16/7/09 by Mr Whippy]
You must have had a bad one, I had one which was stable up to 120mph with a 1.2 TC engine, and went around corners like thing possessed from
possessedville!
If you can keep you head, whilst all others around you are losing theirs, you are not fully aware of the situation
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speedyxjs
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| posted on 17/7/09 at 06:18 AM |
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Iv had a phone call last night to say the rear shock on my Jag are shot. Might be worth checking yours.
How long can i resist the temptation to drop a V8 in?
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smart51
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| posted on 17/7/09 at 07:35 AM |
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quote:
Originally posted by speedyxjs
Iv had a phone call last night to say the rear shock on my Jag are shot. Might be worth checking yours.
How do you check shocks? I've never had to do it before.
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alistairolsen
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| posted on 17/7/09 at 07:59 AM |
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mot testers bounce the car a look for oscillations but that only wrks for relatively soft sustension. If its not a huge hassle Id remove them and the
springs and see if much force is required to move them
No way of knowing if theyre stiff enough, only if they have meaningful resistance to movement
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speedyxjs
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| posted on 17/7/09 at 10:43 AM |
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quote:
Originally posted by smart51
quote:
Originally posted by speedyxjs
Iv had a phone call last night to say the rear shock on my Jag are shot. Might be worth checking yours.
How do you check shocks? I've never had to do it before.
Push the corner of the car. The car should bounce back up and the settle. Mine were bouncing up and down a few times before settling.
How long can i resist the temptation to drop a V8 in?
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smart51
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| posted on 17/7/09 at 06:01 PM |
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quote:
Originally posted by speedyxjs
Push the corner of the car. The car should bounce back up and the settle. Mine were bouncing up and down a few times before settling.
Did this. No bouncing at all. The car springs back up quickly at first then slowing down as it reaches ride height. No overshoot at all.
I also pumped the tyres up a bit more. Some knobend had fitted kwikfit own brand tyres. The book says 23 PSI. They were at 25, I upped them to 28.
This improved things a fair amount. I'll try 30 when the weather dries. I've got to fit some better rubber. The Centaur Supremes are
the shytest tyres in the known universe.
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Gazeddy
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| posted on 17/7/09 at 06:43 PM |
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On the topic of poor tyres we had a car that wasn't even six months old needing four because all the sidewalks have split. Can't remeber
the brand but the tread pattern is called wl-603 which makes me think wanli
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smart51
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| posted on 17/7/09 at 09:17 PM |
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I've just done a quick geometry check with some string and a ruler. The front has 2.25mm of toe in between the pair of wheels, so about 1mm
each and the rear has 1mm between them, ao about 0.5mm each. Moving the wheel spacers makes about 0.25mm total error in the string.
Quoted geometry is 0mm +/- 2 at the front and 2mm toe in +/-2 at the rear so they should be OK.
[Edited on 18-7-2009 by smart51]
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smart51
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| posted on 24/7/09 at 07:42 AM |
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Finally, after several delays from the supplier, I have new tyres fitted. Toyo Proxes CF1 (loads of tyres are not made in 14" fitments). The
grip and handling are transformed. Its still not a seven in terms of handling but it is a match for an MX5 which is what I was expecting.
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