Technical 100HP suspension
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Technical 100HP suspension
"The extra movement however played havoc with the rear damper lower bushes."
Daft question - you did torque up the shocks with the weight of the car fully on the axle? Otherwise that will tear the bushes.
Daft question - you did torque up the shocks with the weight of the car fully on the axle? Otherwise that will tear the bushes.
babbo_umbro
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Sto bene grazie. We're at our Umbrian home for a couple of months, having arrived via a concert gig in Sardegna on the 1st of September.
My previous Panda was a 100HP, which I was very fond of. The rear end was a victim of Fiat's habitual weak return damping, but adjustable Konis on the back made a big difference. The half mile of steep white road to us here has deteriorated horribly over the last three years or so and the 100HP couldn't tackle it, though the 4x4 TA's fine. Beginning to look for something like Konis for the 4x4 but have found nothing so far.
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My parents were from near Frosinone.
It was your instructions I followed when I fitted my Koni's to the back.
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My Fiat 500 springs are stuck in the DPD system. I will have to chase them later.
Cars have really quite heavy axles and wheels so do need good dampers to keep it all under control. Ideally minimal damping on impact but increasing as the wheel moves up. Then strong damping on the return so the wheel does not smack down after the bump.
A sign of weak dampers is a double thump over road bumps. One caused by the bump, the second caused by the wheel coming down too hard.
Cars have really quite heavy axles and wheels so do need good dampers to keep it all under control. Ideally minimal damping on impact but increasing as the wheel moves up. Then strong damping on the return so the wheel does not smack down after the bump.
A sign of weak dampers is a double thump over road bumps. One caused by the bump, the second caused by the wheel coming down too hard.
babbo_umbro
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Fiats have tended to have weak rebound damping over the years especially on the rear - which is why I've spent so much money on Konis - 131 Sport, Ritmo Abarth 130TC, Uno turbo ie, Cinquecento Sporting, Panda 100HP.
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On the 100HP it's aggravated by the shortened (and hard) springs which I'm pretty sure are standard 1.2 materal.
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Yippee! DPD eventually came through with my 500 rear springs. 
What a palarva that's been!
2015 Fiat 500 1.2 rear coil spring free length = 290mm the wire is 11.25mm diameter.
The standard 1.2 Panda spring is 300mm long with 12.25mm wire.
Who knows how that works out in terms of spring rates; though it's said the 500 has 30% softer springs than the 169 Panda.
My wife's Panda 1.2 with 500 springs and base rubbers fitted at both ends, rides at the same height as the 100HP on it's OEM 100HP springs.
I'll measure the 100HP springs when removed from the car but it looks like the 500 springs will give the correct ride height with no mods. They will soften suspension action but body roll will increase. We will have to see how this compares with the 1.2 with it's Fiat 500 axle, and its built-in anti-roll bar.
The 1.2 with 500 springs and 500 axle looked a lot too low with a spring base rubber at the top end only. A rubber at both ends sorted that with the happy benefit of protecting the axle spring pan from abrasion just as it does the body shell paint.
What a palarva that's been!2015 Fiat 500 1.2 rear coil spring free length = 290mm the wire is 11.25mm diameter.
The standard 1.2 Panda spring is 300mm long with 12.25mm wire.
Who knows how that works out in terms of spring rates; though it's said the 500 has 30% softer springs than the 169 Panda.
My wife's Panda 1.2 with 500 springs and base rubbers fitted at both ends, rides at the same height as the 100HP on it's OEM 100HP springs.
I'll measure the 100HP springs when removed from the car but it looks like the 500 springs will give the correct ride height with no mods. They will soften suspension action but body roll will increase. We will have to see how this compares with the 1.2 with it's Fiat 500 axle, and its built-in anti-roll bar.
The 1.2 with 500 springs and 500 axle looked a lot too low with a spring base rubber at the top end only. A rubber at both ends sorted that with the happy benefit of protecting the axle spring pan from abrasion just as it does the body shell paint.
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Removing the road spring and jacking up the axle until the shock absorber stops at the top of its travel leaves a 50mm gap between the bump stop carrier and axle spring pan. That's measured with a depth gauge through the spring pan centre hole. The 100HP tyre side wall is very close to the wheel spats but does not touch the wheel arch. A standard Panda wheel would have inches of clearance.
Who knows why Fiat use a bump stop with a 75mm of uncompressible material and a soft part only 40mm high.
I have some Febi/Bilstein bump tops on order.
The car rides well with 500 springs and (for now) no bump stops. It's still stiffer than the standard Panda but with 45 tyres that's to be expected. On a short spin, I cant detect any more body roll, though there has to be more roll than before.
With a rubber spring seat on both ends of the springs, the ride height is the same as it was with 100HP springs but it is more compliant. That 1mm thinner spring wire does make a difference. The rubbers seat on both ends protect the spring pan paint as well as the body shell paint.
Who knows why Fiat use a bump stop with a 75mm of uncompressible material and a soft part only 40mm high.
I have some Febi/Bilstein bump tops on order.
The car rides well with 500 springs and (for now) no bump stops. It's still stiffer than the standard Panda but with 45 tyres that's to be expected. On a short spin, I cant detect any more body roll, though there has to be more roll than before.
With a rubber spring seat on both ends of the springs, the ride height is the same as it was with 100HP springs but it is more compliant. That 1mm thinner spring wire does make a difference. The rubbers seat on both ends protect the spring pan paint as well as the body shell paint.
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Hi... Have you got a link to the rubber seat spring plz
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They are on ePER Fiat ref 46843237 "Thrust ring". Panda or Fiat 500 rear springs on eBAy often come with the rubber seats. You will have two on the car, so if going for used 500 springs, just get a pair complete with rubber seats.
Eper shows the bump stop at the axle end. On both of my Panda's, the stop is at the top end. The 100HP stop is too long adding to the harsh ride.
These look ok. https://www.ebay.co.uk/itm/2015-FIAT-500S-1-2-REAR-COIL-SPRING-PAIR-PETROL-8997/253324983592?fits=Car+Make%3AFiat%7CModel%3A500&hash=item3afb587d28:g:7dsAAOSwUchaPOti:rk:9
f:0If you want to stop standard springs rubbing the axle pans you can slide some reinforced rubber hose along the spring. You need to get the correct hose size but 15mm bore will do the job. Use lots of red rubber grease so they cover one full coil plus another 1/4 turn.
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They are on ePER Fiat ref 46843237 "Thrust ring". Panda or Fiat 500 rear springs on eBAy often come with the rubber seats. You will have two on the car, so if going for used 500 springs, just get a pair complete with rubber seats.
Eper shows the bump stop at the axle end. On both of my Panda's, the stop is at the top end. The 100HP stop is too long adding to the harsh ride.
These look ok. https://www.ebay.co.uk/itm/2015-FIAT-500S-1-2-REAR-COIL-SPRING-PAIR-PETROL-8997/253324983592?fits=Car+Make%3AFiat%7CModel%3A500&hash=item3afb587d28:g:7dsAAOSwUchaPOti:rk:9
If you want to stop standard springs rubbing the axle pans you can slide some reinforced rubber hose along the spring. You need to get the correct hose size but 15mm bore will do the job. Use lots of red rubber grease so they cover one full coil plus another 1/4 turn.
That’s great info mate ?? This is gonna be one of my jobs over the new year, as well as a good complete service and full fluid change. ??
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It's to limit body roll without having the cost of an anti-roll bar. Car sits on the bump stops on hard cornering, which isn't ideal if the road isn't smooth.
I'm running Eibach springs on standard shockers. Sits 20mm lower but there's no issue with ground clearance. Handling is just as good, ride quality is massively improved.
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There are far too many speed bumps (and c**p roads) around my way to risk lowering the ride height. A rear ARB will also stiffen the ride but using extended bump stops is (IMO) close to a bodge.
Ford used Fiat to make the new Ka but demanded that Fiat fit an ARB to the back axle with softer springs. That axle later went into the Fiat 500 though early 500s had the old stiffer axle. The ARB version uses a 30% softer spring that rides pretty much at 100HP floor height.
The standard 100HP springs have the same wire as a 1.2 Panda but shortened so feel a lot harder. Short bump stops make it loosen your fillings.
I'm running 500 rear springs in the 100HP, currently without bump stops (another job for the list). There is surprisingly little additional body roll though you can tell on the limit. But overall, it handles better as the back wheels are not skipping about.
When I replace the suspension, it's going in with 500 springs front and rear. A softer ride, but if the back end mod is anything tho go by it will improve the car overall. If not, it's cheap to do and easy enough to go back to standard height springs.
I would love to fit a 500 axle (have one in the 1.2 Dynamic) but it is 50mm wider than the Panda axle and while ok with narrower wheels, it's too wide with 100HP wheels.
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