Porsche Enthusiasts Club Forum

If you have fitted the standard 16"s and it still tramlines maybe it is a particularly bad section of road with a serious camber. Or maybe it is as suggested suspension i.e. struts or wheel alignment was this set up after the work you say was done replacing bushes etc.

I currently run 255/40/17 & 225/45/17 on my 944S2 and it tramlines on badly cambered roads but I just accept this is how it is and without going back to 16" 205s on the front I don't think it will improve, although I am going to fit new tyres soon and am thinking of reducing both front and rear widths by 10mm with 215s on the front to see if this improves things. But as my local Porsche expert explained to me the 944 was never really intended to run 17" without 968 castor bushes etc and even then will suffer from tramlining.

David, thanks for your kind advice, you have renewed my faith in this forum because I was just being told off before!

Gary, arent you a little old for silly wheels? Hmmmm? You should have saved up for a more suitable Porsche to put your blinged up rims on.

You havent answered my question about the wheel widths and their offsets. 944s dont ride very well and they follow overbanding on the road with 215/60/15 tyres. Wider tyres and less compliant sidewalls amplify this shortcoming and it will be made far far worse by fitting incorrect offset front wheels.

Im sorry but 'Promax sell them' is far short of an endorsement. They dont work with the car and even if everyhting else is as good as it can be, its still going to ride like a tea tray and follow every mark on the road.

I would regard a Porsche specialist such as Promax and Victor Equipment wheels as a better endorsment than a relatively new forum member, but since my blinged up rims dont suit you I can only appologise.

So: you consider a specialist who chooses to sell a product to be in a better position to advise you than the manufacturer...?

That aside: I may well be a 'new' forum member, but I know better than to fit current blinged-up wheels with mismatched tyres onto a twenty year old car, which they neither suit nor are suitable for.

I think that it would be a mistake to confuse my low post count with a lack of experience.

There's no need to be offensive Gary. People on this site are very knowledgeable and very helpful - they could even help you with your spelling! You asked for advice and you're getting it. We could all just bullshit you - but that's no use to anybody. Your wheels look very nice, but they're not right. I'm afraid that you have been 'sold to' by a wheeler-dealer (that's clever isn't it) and now you're suffering the consequences. Maybe you should drive along the same 'tramlining' road in your mum or dad's car to see if it is the road, practically all of the inside lane of the M6 is like that up here.

And your number plate is illegal...... but I suppose that like the wheels it looks nice - and I bet the specialist said you'd get away with it!

On a serious note - I hope you have told your insurance company, because if you haven't and cometh the day.....

You haven't answered my question about the wheel's offset, the front's particularly. Also: you say that you have new 968-type compliance bushes, which is good, but have the strut mounts been replaced? I'm guessing not because they're very expensive (to suit M030 especially). Unfortunately wear here will become more evident as wheel size and tyre harshness increases.

You can answer when you come off the naughty step.

Promax. Well, you are evidently a new member of the community. They wouldn't be allowed to touch any car of mine, let's just put it that way. Next time you're there ask them the perfectly reasonable question which dealer they did their training at. 2 real specialists in the UK trained at the factory (Steve Bull and Jon Mitchell), and the majority of the rest at a dealer. The others are entirely unqualified save having worked on the cars before. You might argue that that doesn't make much difference but I think you have just highlighted one of the areas where it most definitely does. Properly trained technicians also tend to have all the proper manuals and specs which might be hard to come by for someone untrained, assuming they even know such documents exist.

As Jim said Porsche don't recommend greater than 17" wheels on a 944. In fact he was a bit remiss as they explicitly forbid it in a technical bulletin stating quite clearly it is dangerous, so that's how "specialist" Promax are. Now I don't like being told what to do any more than the next guy and I have run 18" wheels on a 944 for well in excess of 100,000 miles, but I knew they were on the edge of ruining the drive (they were over that edge on my cab which could not be kept within 3 feet of the intended line on a bumpy corner with them) and you will never get 19s to behave. Americans my well run 20s, but as a nation they are broadly ignorant in my experience (apologies to any reading this, clearly many are not, but without exception those I have met in that category agree enthusiastically with my generalisation).

The wheel manufacturer might well make exclusively wheels for Porsche, but that doesn't mean all are intended for a 944. At the end of the day though it's your car and if you like the look and are prepared to put up with the compromise then it's your prerogative and I'm all for freedom of choice.

Simon may be relatively new to the forum, so ignore his advice if you like. What I can tell you is that in the short time he has been posting he has demonstrated to me (via the PCGB forum) that he is one of the most knowledgeable forum members I have run across when you're talking 944. Ignore me as well by all means, but be aware I have been in the community since 1994, I've had 8 Porsches including 944 S2 coupe & cab plus 3 Turbos, one of which is very extensively track focussed and has been rebuilt in every area bar the transmission.

Specific to your problem there is an issue if the car tramlines badly with 16" wheels. When you say "968 bushes" have been fitted what exactly do you mean? Unless the road surface is extreme you shouldn't get any significant nastiness with the original wheels. If you do then there may be one or more of a number of causes:

Tyre pressures wrong or mismatched
Geometry out
Excessive lowering
Wear in bushes
Wear in struts
Unbalanced wheels
Unusual wear pattern on tyres
Bent chassis
Bent or damaged suspension component

To John and 944man, I'm sorry how this has panned out and I know your only trying to give advice which I'll take on board but try to be a little bit more diplomatic in the way you try to advice people. As I've said before the car runs fine on good roads if not better then before. It's problem lies on this road where even my Astra tramlines. All I'd really like to hear is advice on what tyre pressures people are running with the same set up as mine because I know there are others out there though they may only be in america. Any way sorry again for opening up such a big can of worms (my spelling and my bling wheels) And upsetting any one out there. Maybe I'll stick to the beema forum. Hope your watching Stu lol

Nobody I know runs 19s so you won't get any advice on tyre pressures from experience, unless you try asking on Rennlist, but if you do then be aware greater than 50% of posters on there are idiots and you need to consider any advice seriously before you follow it.

At a guess I'd say you'd be looking at low 30s psi all round. Most people run somewhere between 34 and 36 in 17" tyres, either the same all round of a hair lower at the front. With less sidewall flex you'll want to drop from that a bit. With my track tyres I aimed at 29 hot and those sidewalls may be close to as stiff as your 19s, so you might even want to try that low.

You could try the old trick of making a chalk line across the tread and then driving a bit and seeing where it has worn off first. If it's the middle then you have too high pressure and if it's the edges it's too low. In practice with your tyres you'll probably find the edges would go first at low speed and the middle at higher though as the sheer width of them will allow the tread to bow out under centrifugal force and you'd need lots of pressure to keep it firmly pushed into the ground rather than run on the base of the sidewalls at low speed.

Thanks Fen for the info. I'll give it a go when I wheel the old girl out again, weather permitting. When I first tried the wheels the fronts were on 32psi and I've since took this down to 31 which I must say was better but since then I've not had a chance to drive it again. I'll drop down to 30psi run your test and then down to 29psi and try again. I know about the rennlist forum and have also posted the same question on there and do agree about the idiot thing. I'll post the results as soon as. I've only just come back to the 944 world after owning one many years ago and must say I'd almost forgot what a good car they are even by todays standards. It's good to drive with a smile back on my face. Any way thanks again Fen and to everyone out there and I'll try and curb my to tongue in the future. Gary

You haven't stated the front wheels width and offset. If this is wrong (and I suspect that it will be) then the car isn't going to steer very well. Originally the car had a 7" front rim, with a 53mm offset. Inboard space permitting, you need to decrease the offset by 12.5mm per extra inch of rim width added, in order to keep the centre of the wheel where Porsche intended/expected, when they designed the steering geometry.

Thanks Simon, yes someone told me this before but I can't remember what the front offset was. When I drag her out again I'll look what the offset is and let you know. Thanks again

Gary,

More comments telling you that you are wrong, from a forum member with a very low post count ... ... but I think that your wheels are too big as well. And that will be the cause of your problems.

However, you asked about pressure. You may or may not be familiar with The Wheel And Tyre Bibles by Chris Longhurst, but they are very good. Link here:

http://www.carbibles.com/tire_bible.html

His recommendation is to look at the maximum pressure of the tyre, knock 10% off, and inflate to this pressure. It seems to work in my experience as well ... (see the bottom of Page 2 for more of this.)

FWIW, I run 38psi all 'round in the standard size tyres on my D90's. Not that this is of any use to you.


Oli.

WOW!

thats the first tipec forum argument i've seen

Is that toms old car?...I must admit i think it looks well on the new wheels but it does seem a shame to compromise the handeling of such a great drivers car for aesthetic reasons.