I thought your car already had Volvo V70 rims. What size and offset are the old and new ones.?

The car had Volvo T5R rims with 215/45/17 tyres, the 'new' rims are 15" 5 spokes fitted with 195/60/15. I'm not good with wheels and tyres really, never been that interested. Once I'm sorted out I need to have a trip with the sat nav to see how accurate (or not) the speedo is.

According to the place where I go the replacement alloys the ones already fitted are worth quite a bit so they will going very soon to release some funds. A chap there offered me £250 for them but the gaffer had had already told me they could fetch upto £400. They seemed quite distressed that such wheels had been fitted to an old Citroen or maybe it was me telling them that they spoilt the ride.

Steve.

I can understand the low profile tyres causing jitter and tramlining.

The tyre sizes you have there give rolling circumferences of:
195/60-15 = 1932mm
215/45-17 = 1964mm

Is 195/60-15 the correct size for your car.?
If 195/65-15 is correct that gives a RC of 1993mm so both other sets of tyres will create an undergeared /speedo over-read situation.

The offset is how far from the centre of the wheel the hub mounting face is. It will be given as a figure after the 'ET' marking.
The offset has to vary depending on the rim width so to clear the suspension leg but not alter the steering axis too much.

As far as I know it should be on 205/60-R15 so apart from a small drop in width the larger profile will help raise the gearing slightly which I'm happy with, I find it quite low geared. So a trip with the sat nav will be needed.

The offset is the same for both Volvo rims and the XMs.

It's nice to be driving the car without it twitching and grabbing. It was particularly bad when crossing the tramlines at a narrow angle.

Thanks for the details.

Steve.

Owners handbook gives 195/65/15 for 2 ltr injection Mk2 but 195/60/15 for a 2 ltr injection Mk1.

John

Hi Steve

Have I read elsewhere u were planning to put 195/65 on your car? If I'm wrong, sorry, just bad memory.

If so, I'd strongly advise to not put less than a 205 width on a tct or a V6 or a 2.5td, for safety's sake (even if you drive "slowly" etc, I also do).

The 205s' grip is really limit for the front of the V6 in wet tarmac -it slides too easily sometimes-. I'd imagine the tct is essentially similar overall: torque, wheight (though the V6 should be carrying a few more kgs in front, but no so many more as people believe).

I'd put personally 205/65/15 on a tct for comfort, or ideally 205/60/16 for increasing the grip threshold. My car is on 205/60/15 which are a bit "too few" of tyres for the weight of an XM really (I don't want to imagine their wear and performance if I ever went to drive this XM seriously fast in twisty mountainous roads like I often did when I was younger). A V6 ideally needs 215s in my opinion but these are difficult to find in my experience -seems manufacturers nowadays either put 205s or go for 225s-.

Personally from all cars I've driven I came to conclude that the 60% profile is the best compromise between handling and grip. Above that (65 etc), the tyre really folds when cornering, so you don't use its well-designed thread, less than that and it becomes annoyingly stiff to bumps and car tends to follow ridges and road inclinations irritatingly so, even when u drive on a straight line (as I m discovering with my girlfriend''s Fiat Coupe on 225/50r16 that thinks is a crab and needs constant correction at the steerring wheel on motorway).

Just my opinion, but I think in a tct on 195/65/15 you'll find your front struggling not to slide in smaller roundabouts/sharp corners on wet weather, just at normal speeds. Keep the 195s to base-2lt versions max.

cheers
George

Hi George,

Thanks for the input. Currently the alloys are fitted with 195/60/15 so I'll get a feeling for how she handles with them. I'll have to check out the cost fitting/implications of 205s on those alloys I've got.

Sorry to hear of all your problems with the water pump saga, hopefully you'll get it straightened out soon.

Last night I discovered a water leak on the engine. It's where the LPG vapouriser taps into the heater circuit using T pieces. It seems as though the T has a pin hole in it. this isn't good because apart from the obvious drop in coolant and the danger that brings, it's also wetting the ignition coil and ABS connector. Leaving the expansion cap loose stops the leak and allows me to drive the car to work. I was wondering if I can make up my own T piece using 15mm copper fittings, I need to check the bore of the heater hoses after work. Hopefully it'll be suitable, I've got plenty on copper endfeed fittings and pipe and it'll be stronger than the plastic T that's currently fitted.

Steve.

Hi Steve

Indeed if u new alloys are 5" wide, it's a bit tight for 205s. Will later go out and check how much my "wobbly" alloys are -I seem to remember their dimension was printed at the outer side-. They were 5.5" or 6", but not sure.

Incidentally yesterday was looking at a french forum where there was a base-model XM presented, 2lt non-hydractive, with carburators, no armrest, etc etc.... and this is factory-fitted with 185/65/15 !!


Ah, cooling problems on old cars are the most obscure sometimes...Only now, after 4 years, I have fully sorted my cooling (with this waterpump change). I'm confident you'll find a good solution to this leaking T-hose!

cheers
G

Hi,

I did find a solution to the leaking T pieces. Upon dismantling the joints I found that plactic parts have been used. Not the hard plastic ones used by car manufacturers but the more general hose pipe/irrigation types, these obviously don't like tight hose clips when heated up. They had actually began to fold inwards creating a small channel that allowed the water to squeeze through. Another poor aspect of the LPG installation was that the hose sizes on the vapouriser and then cars heater circuit are different so 19mm T pieces were used then 19mm to 10mm reducers used. This not only meant more joints to leak but also the running of thicker pipes than necessary which doesn't help in a cramped engine bay. One of the T pieces was tight up against the coil pack/ignition leads. Two 19mm hoses squeezing in the gap between the coil pack and the LHM would probably lead to chafing.

So I ordered proper metal T reducer pieces and 4 metres of 10mm hose from Tinley Tech. The piece of heater hose that linked to the thermostat housing was too short to allow the T piece to be located under the coil pack (I assume that how it should be?) so I went to the scrapyard to scrounge what I could. I found exactly the size and shape I needed on a Laguna and it even has a bleed point on it. Now the T piece is under the coil pack and not rubbing on anything. The other 19mm vapouriser hose that crossed the bulkhead from the other heater pipe has also been replaced with 10mm hose. It's much neater, now I only have to tidy up the LPG wiring.

Steve.

That sounds like a complex heating pipe arrangement!

On my 2.oi Turbo Onyx here, when I put it in I didn't cut ANY pipes what so ever in the system, in stead studied the coolant circuit and found that the Cylinder head OUTLET from above the thermostat that goes BACK to the expansion bottle had adiquet outlet of water AND also got warm quite quickly, so I fitted a pipe from the outlet, into the bottom of the vapouriser, then out the vapouriser to the expansion bottle... and it has worked perfectly for the 10k miles I did in her NO PROBLEM... because it was in a return circuit there was no air problems either...

Shame the PRV hasn't got the same type of cuircuit, it is different, and mine has been tapped from the heater hoses... luckily I have a couple of spares of them, as Ive been told they arent available anymore.. :-o

Rgds
Paul

I wouldn't say it's complex, it was just badly done. Using plastic parts just made it worse. Hopefully it's all OK now.

Steve.