Problems with my rear end!
Discussion
I've been having some issues with grip on the rear wheels and wondered if someone more knowledgeable could shed some light or offer some advice on this.
Current set up is 205/60R15 Toyo 600-F5 tires on the rear (Toyo CF-1s on the front) on the standard Oz 5 spokes and S1 trailing arms. I haven't confirmed the trailing arms but due to the massive squat I get under acceleration (Longers can confirm this one!) I think they probably are the S1 fully trailing variety.
The problem I have is the amount of grip the rear end has, a few incidents have worried me and I don't think there is as much grip as there should be, especially in the wet.
My concern about this kicked off during the Euro trip. Going round hairpins in the wet very slowly with only enough power to take the engine braking away I was still sliding the rear out. Someone commented I was going really slowly and that they had no problems with rear grip. My (nutty) co-pilot also managed to get the rear out in the dry round every hairpin on the Petit St Bernard pass when others were saying they couldn't even at full throttle in 2nd. He also almost spun us on a motorway sliproad in the wet. It was one of those straight french sliproads at a fairly low RPM and as soon as he put his foot down the tail was snaking all over the place which was a life shortening experience
The only things I can think are wrong are that the tires are rubbish or inflated incorrectly (although the pressures are as they should be according to the Bible)
Does this sound like I need some new rear tires as thats the only solution I can think of.
Sorry for the huge post!
Current set up is 205/60R15 Toyo 600-F5 tires on the rear (Toyo CF-1s on the front) on the standard Oz 5 spokes and S1 trailing arms. I haven't confirmed the trailing arms but due to the massive squat I get under acceleration (Longers can confirm this one!) I think they probably are the S1 fully trailing variety.
The problem I have is the amount of grip the rear end has, a few incidents have worried me and I don't think there is as much grip as there should be, especially in the wet.
My concern about this kicked off during the Euro trip. Going round hairpins in the wet very slowly with only enough power to take the engine braking away I was still sliding the rear out. Someone commented I was going really slowly and that they had no problems with rear grip. My (nutty) co-pilot also managed to get the rear out in the dry round every hairpin on the Petit St Bernard pass when others were saying they couldn't even at full throttle in 2nd. He also almost spun us on a motorway sliproad in the wet. It was one of those straight french sliproads at a fairly low RPM and as soon as he put his foot down the tail was snaking all over the place which was a life shortening experience
The only things I can think are wrong are that the tires are rubbish or inflated incorrectly (although the pressures are as they should be according to the Bible)
Does this sound like I need some new rear tires as thats the only solution I can think of.
Sorry for the huge post!
I did check the age a while ago and I think they are about 4 years old so probably nearing the end of their useful life.
As to pressures i set them to 24psi when cold and they were at a reasonable temperature when I've been 'enthusiastic' in the dry, probably 30 degrees or so. I've never checked in the wet but I imagine much cooler.
Is there any way of figuring out the correct pressure other than trial and error?
As to pressures i set them to 24psi when cold and they were at a reasonable temperature when I've been 'enthusiastic' in the dry, probably 30 degrees or so. I've never checked in the wet but I imagine much cooler.
Is there any way of figuring out the correct pressure other than trial and error?
This may be complete horse s
t but my 2p.
I reset the ride height on mine (S2 on adjustable shocks) at the end of last year and the handling has improved considerably. Could it be that everything is a little tired and could need refreshing. I appreciate that this may mean new bushes/suspension etc but just some thoughts
t but my 2p.I reset the ride height on mine (S2 on adjustable shocks) at the end of last year and the handling has improved considerably. Could it be that everything is a little tired and could need refreshing. I appreciate that this may mean new bushes/suspension etc but just some thoughts
I think we may have mentioned at the time, but following you down the Petit St Bernard the back end of your car looked to be rolling excessively compared to others. I don't know what state your shocks / springs are in but a bit of investigation in this area may be worthwhile.
Possibly a long shot, but may also be worth checking that the ARB and it's associated bushes, links etc are all in good order and operating as expected. I know they're only fitted to the front but since the chassis is fairly stiff it's conceivable that a problem in this area could also contibute to what's going on at the rear... or am I talking a load of rubbish?
Possibly a long shot, but may also be worth checking that the ARB and it's associated bushes, links etc are all in good order and operating as expected. I know they're only fitted to the front but since the chassis is fairly stiff it's conceivable that a problem in this area could also contibute to what's going on at the rear... or am I talking a load of rubbish?
The state of the shocks can make a big difference but it is most likely to be the age of the tyres as the compound hardens with age. Tyre life is about 5 years regardless of wear. I had an old Citroen that was positively dangerous on old tyres till I changed them.
I find the S behaves realy well even in the wet. (did have a minor scenic excursion in the snow though)
Rob.
I find the S behaves realy well even in the wet. (did have a minor scenic excursion in the snow though)
Rob.
As the car isn't in Southampton with me at the moment I'm going to see if I can get my dad to confirm the tyre dates.
As for the suspension, I have no idea what condition the rear bushes are in but getting the trailing arms off and powder coated is on my to do list so I'll replace the bushes at the same time.
I currently have Avo adjustables that were fitted in 1997 by the history. They seem ok with no weeping although the springs probably need a lick of paint. Is there anyway of figuring out the spring rates from looking at them?
The anti-roll bar got removed last weekend and the bushes seemed in good shape. Still has standard drop links though which I plan on upgrading to the rose joint variety soon.
Thanks for your help everyone!
As for the suspension, I have no idea what condition the rear bushes are in but getting the trailing arms off and powder coated is on my to do list so I'll replace the bushes at the same time.
I currently have Avo adjustables that were fitted in 1997 by the history. They seem ok with no weeping although the springs probably need a lick of paint. Is there anyway of figuring out the spring rates from looking at them?
The anti-roll bar got removed last weekend and the bushes seemed in good shape. Still has standard drop links though which I plan on upgrading to the rose joint variety soon.
Thanks for your help everyone!
orange_dodo said:
Is there anyway of figuring out the spring rates from looking at them?
Yes. Measure the coil outer diameter, the wire diameter and the number of free turns then plug them into a spring rate calculator, such as:http://www.reliablespring.co.uk/calculator.htm
Have fun!
Graham
Cheers Graham I'll have a look. What are the suggested spring rates BTW?
Right well results on my tyre age are in. Fronts are 4th week of 2006 so it's their 5th birthday this week!
Dad couldn't find the DOT code for the rears (maybe on the inside edge) but I haven't got any receipts for tires since 2006.
I think it's time for new tires then!
Right well results on my tyre age are in. Fronts are 4th week of 2006 so it's their 5th birthday this week!
Dad couldn't find the DOT code for the rears (maybe on the inside edge) but I haven't got any receipts for tires since 2006.
I think it's time for new tires then!
orange_dodo said:
What are the suggested spring rates BTW?
I refer the honourable gentleman to the answer I gave in November of last year:http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Regards,
Graham
Ragtop said:
orange_dodo said:
Is there anyway of figuring out the spring rates from looking at them?
Yes. Measure the coil outer diameter, the wire diameter and the number of free turns then plug them into a spring rate calculator, such as:http://www.reliablespring.co.uk/calculator.htm
Have fun!
Graham
) whilst doing about 15mph (normally can take that roundabout at over 30 in the MondeoGassing Station | S Series | Top of Page | What's New | My Stuff