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MG MGF Technical - Ride Height
Checked my ride height today and found the following Front right 335mm from hub centre to wheel arch Front Left 330mm Rear right 340mm didnt continue!! So any one know what sort of price to "pump the pressure back up" and does it have to be an MG dealer ???? I can only assume this isnt doing anything for my steering wobbles! |
Tony |
BTW - the car hasnt been driven since yesterday and its quite cold here in wilts today! |
tony |
been quoted £30 including fluid! |
tony |
Tony I wouldn't bother unless the car is grounding out, mine drops a huge amount in the cold weather and then pumps itself up in the spring. Also the back wheel heights are governed by the front so dont bother taking those measuremens. But £30 sounds about right from a dealer but if you can find a 'railway arch' man who worked on Metros and has the Hyrdogas pump then you will get it done for a tenner. Ted |
Ted Newman |
I havent noticed any grounding out - just read that anything under 350mm tends to lead to the system not being able to work properly and as mine is 330mm that seems to be pretty low! Of course - it looks better lower :) So if anyone can confirm this isnt causing my wobbles i will leave it and get my tracking sorted! |
tony |
Tony, if it's going fine than let it as it is. Tyre wear at the front wheels should be checked if you havn't done already. (inner tyre surface must be nearly equal to the outer). But if you have any doubts cause wobbly behavior on side winds, tram line following or wobbly feeling at higher speed, than let it pump back on about 350mm on both front sides. I would recommend a hight correction in next spring if it gets warmer to keep the current nice look. Whatever you decide, the 30 quid seams OK so far. Take care that they just count more than 1 quarter litre fluid to get it back on 360 from 335, cause not more is required (3.50 quid for 1 litre). Also the tracking needs no correction if no other problems are to be complained. Cheers Dieter |
Dieter Koennecke |
Dieter I have had a look at the front tyre wear and its definately wearing on the inside edges of both - Also the higher speed wobble seems familiar so I am going to get it re inflated to about 360mm and then get the tracking etc checked |
tony |
Also i HAD TO HAVE 205 NCT3S FITTED to the rear as there were no F1s so I may fit 205s all round and swop the rears to the front and find some F1s for the rear - is this a good idea ? Just trying to save money and get some decent tyres on the rear without throwing a brand new pair of tyres away! |
tony |
What was the ambient temperature when you checked the ride height Tony? It was close to freezing here this morning, and the ride height needs to be checked when the ambient temperature is 17 Celcius. The correction is 4 mm for every 10 degrees celcius difference to that 'set temperature'- so your car is perhaps 8 mm lower than it would be under 'normal' conditions. Even taking this into account, your car IS riding a little low. Low end of 'manufacturer' spec is 358 mm. At 'normal' temperature, the lowest ride height without other suspension modifications is 350 mm. However, if you are not experiencing problems with the suspension at this height (note that it will 'self raise' after a journey around the block), then why fix what isn't broken? If you do decide to pump the suspension to manufacturer spec, then use your local neighbourhood garage. If they can service Metro suspension, then they can raise your car's suspension. It WILL be a good deal cheaper than your local MGR dealer- I spent a fiver at my 'local' and whilst your car is almost certain to end up in 'LandRover mode' you'd expect this from the MGR dealership too... Easy to lower the car to the height you desire yourself using the rule of thirds... :o) Regarding the tyres, I shall default to my usual safe advice on this: always fit the same brand and type of tyre to all four wheels. Mixing IMO is not a great idea although some say that F1s and NCTs go okay together. Wider 205/50 NCT-3s on the front? You are entering uncharted waters there Tony! |
Rob Bell |
HMMMMMMMM i will take it for a spin tommorow and test after it has risen to a "normal level" was about 8 deg when i tested and not driven - if itmakes about 350 i will leave it alone - just thinking if the tracking is out and the ride height is a bit low this could well be why i am not too happy with the steering/handling! Didnt think about the metro theory - will nip over to the garage in the morning and see if they can do it if needed Tyres - o well 195 or 185 on the front ??? Then tracking Then speedingggggggggggggg :) |
tony |
I'm with Robs opinion (what else) :) IMO it would be not bad to having new F1 at the rear and slight worn different Goodyear on the front. Please don't see this as recommendation, just my thought. You need to find out yourself and I think you can ... BUT at first set the height to below 368mm for a good look. 350mm at this cold ambient temperature will be OK. Take the car for a ride after the height correction and do the following test to make sure that no else unknown trouble makes the costs for track alignment useless: - 30 mls/hour on a good straight non or very low cambered motorway in HIGH gear (4th/5th). Than play with the accelerator and increase/decrease speed slightly. Does the car go straight ahead ? It should (nearly). If it doesn't than the REAR suspension may be worn and you need not pay for a alignment before you didn't try/attach the compliance washers. (think on the toilet sealing washers) next test is - 30 mls/h in LOW gear for a more aggresiv accelerating/decellerating on the same road. The car needs to lift/dive at the front for this test. If it steers to the right or left, than you should at first do something at the front suspension, cause while diving/raising the front toe chages different on the right or left. If you are satisfied, than let the tracking adjust to toe IN as mentioned. If you like, than repeat the above test to make sure that everything is OK with the car. Atr last I would swap to the tyre repolacing. Rear 205 to the front and F1 205 to the rear. Test again ... The above explained with my restricted low budget english. Hope you get what I mean. ... and just my opinion to do things step by step. If you decide to something else than keep in your mind that no tracking adjustment should be done 'just after' having installed tyres. >The tyres should wear in for several miles at first. Due the 'settle time' of the suspension after ride height correction or a hot ride, I'd like to explain, that the strong rubber parts of the suspension are most involved. These are the subframe mounts and the control arm bushes. So if the car stood on an uneven cambered place it will need 2 hours and more to get it settled. (released handbrake, though) HTH Dieter |
Dieter Koennecke |
The saga continues Went and got the tracking checked today - It was toed in by a small amount - so decided to reset to standard toe out by ROVER to see what difference it made! Anyway it has made NO difference to the steering whatsoever - just as touchy as before - maybe a little more controllable on the oversteer! sTILL LIKE A GOKART I have been out for a 3 hour drive - and on my return checked ride height - Front right 345mm Front Left 335mm - Now its a cold day 14 DEG C but i have been driving it fast so would have expected a higher reading than that! It doesnt pull to one side or the other under acceleration or braking So all I can think of is that the hydrogas fluid is too low - so the suspension isnt working properly - it does feel boat like when steering from side to side - but doesnt sway after you straighten up - it just isnt snapping back as a car should if that makes sense You can compensate for the oversteer by leaving turning into a corner very late and putting more pressure on the suspension My suspicion is not enough pressure in the spheres - so has the hallmark of a leaking/broken shock absorbers Finally - there is a cross member running across the front of the car - between the wheels with an arch facing down in the centre - this looks like it has had a knock - not mishaped - but two dents in it - I thought this may be the problem - but the car doesnt pull to one side and the tracking etc is now correct! I have booked a local garage to refill the hydrogas on tuesday - if this doesnt fix the problem the car can go back to the dealer and i will buy something else that isnt as fussy! Needs two new fronts tyres now - getting expensive already! |
tony |
>something else that isnt as fussy! But boring, so boring, Tony ! And no funny support chats. So you got a good straight ahead going car. Great !! some missed this already. Sir Lucas left out steering and sterring rack troubles at yours. >Finally - there is a cross member running across the front of the car - between the wheels with an arch facing down in the centre - Black painted bar, nearly box profile, with towing rings at both sides ? So the front subframes front bar. > It was toed in by a small amount - so decided to reset to standard toe out by ROVER At the rear ?? Ohh, in any way you shouldn't. Toe IN was our advise. :) § 1 NEVER TRUST IN MGR RECOMMENDATIONS BEFORE YOU VERIFIED AT THE BBS, FOC games of a dealer is another case !! § 2 ask at this BBS for hints § 3 if you got any trouble with an MGF out of warranty than loop to § 2 Anyway, nothing more than ride height correction now. Both sides equal, or the Drivers side 2mm higher than the co-drivers if you like and than Toe IN to the rear. HTH and head up ! Dieter |
Dieter Koennecke |
Grins The cross member i am talking about isnt black box section - lookes like a protection part for the underside so assume its done its job :) The front is set to slightly toe out- rover spec - it was 2mm toed in They wouldnt touch the rear!!! - said they couldnt adjust ???? assholes!! Anyway - ride height to be done tuesday - then it better handle like its on rails :) |
tony |
When you measure "to the wheel arch" where are you measuring to? Is it to the paintwork or just to the wheel arch liner. It's about 5mm difference imho. I'm never sure where to measure to. |
Andy |
to the paintwork, not below to the rubber lead. BTW 5mm is 'nothing' but only academic presision. Both sides nearly equal is more important. Another one. If the front to rear difference got checked once very sensitive than you never need to check the rear again, but only both front sides ... until any mad dealership gets hands on any suspension works. They often forget or swap the washers between hydragas piston and knuckle joint and suddenly you wonder about 'new' differences beween front and rear or not equal measurements from right rear to left rear. |
Dieter Koennecke |
Forget checking the rear when adjusting height, front and back hydragas is connected, so if the front goes up so does the back. Anything else can be worked out later. 30 quid sounds about right, a bit of a rip off IMO, but that's what nearly all of them charge. Get them to pump it up over and set the final height yourself when you get home. Also important when checking the height to make sure the car is on a flat even surface and that the hand brake is off. Example of what happens if you have the handbrake on, next time you pull into a petrol station, come to a sharpish stop and imediately pull on the hand brake before releasing the foot brake. Get out of your car and you will see the front is at about 320-330mm. I would say that around 350-355 is a good height if you have a standard car with no lowering knuckles fitted, any lower could put stress on the hydragas units, causing them to fail. The system will work lower but the ride may be a little harsh. With knuckles you can go lower, Personally I would go no lower than 340mm as I would never get my car over the speed bumps outside my house, also my K&N pipes would be dust (even with tom's bracket). See FAQ for more detailed info on setting height and a thread from last week where I and others went into more detail. One more thing, if you are going for a lower setting it may be worth going for a toe in setting for the tracking at the front. I find any tyre bigger than 195 on the front tends to tramline, a lot. If the inside wear on the tyres is bad, try a toe in tracking setting at the front. 195s do tend to give less understeer than std 185s. Do not use a toe out setting at the back unless you have pollybushes or at least compliance washers fitted. And ditch the NCT3 for something better next time you get them changed. |
Tony Smith |
Well as said i reduced tyre pressures and went for another spin today - car feels much better and more predictable on lower pressures - wiered huh - anyway I am a fast driver so have the splitter coming to see if that calms things down a bit at speed Tuesday the K&N is coming and also having the hydrogas system reset to about 360mm Must admit if this doesnt work I will be sending it to techspeed - pay the money and get it sorted - Cant have a sports car that doesnt handle!! |
tony |
>> I have been out for a 3 hour drive - and on my return checked ride height - Front right 345mm Front Left 335mm - Now its a cold day 14 DEG C but i have been driving it fast so would have expected a higher reading than that! << >> So all I can think of is that the hydrogas fluid is too low - so the suspension isnt working properly - it does feel boat like when steering from side to side - but doesnt sway after you straighten up - it just isnt snapping back as a car should if that makes sense << Tony, yes the car is still too low. Basically as the system is depressurised, the spring and damper rates both drop too. With ride heights of less than 350 mm (that's less than 300 psi in the suspension system) the suspension becomes so soft that the suspension simply spends most of its time bouncing off the bumpstops resulting in a poorly controlled and harsh ride. Increasing the suspension pressure will certainly improve things markedly. But remember to recheck the tracking having got the car at a stable ride height. Glad to hear that the tyres pressure change has improved things slightly. |
Rob Bell |
Thanks to all that have helped - feel confident that the main prob is the hydrogas pressure - better be! Suspect the rear bushes are weak also - so odering polybushes now - easy job! Still tempted by the techspeed set up :) Splitter coming tommorow now :( K&N thursday :( delays delays! Geez - better book a week off :) |
Tony |
<<Geez - better book a week off :)>> Splitter and K&N, you could probably manage to fit in a lunch break. |
paul weatherill |
Tony, Be tempted by Tech-Speed. You can do no better for handling. Save the wheel alignment money and ride height money as TS will do this anyway. They'll also fit the polybushes whilst they're at it. Basically, just call Roy or Marvin and ask them to sort out your car's handling. You won't regret it. Dave |
Dave |
Paul - I meant i will need a week off driving it :) Although knowing me and cars falling off jacks I may spend the week under it!!! Well tempted by the techspeed - but £800 ouchy mmmmm - but then awesome conering - mmmmmm --had their number in front of me all day today - lol - but managed to refrain -- wont last -- but then i could get a set of split rims instead and just wobble n pose!!!! |
tony |
Go on, go on, go on, go on, go on, go on, go on, go on, go on, go on, go on, go on, go on, go on, go on, go on, go on, go on, - you know you want to. <mmmmm - but then awesome cornering - mmmmmm > Absolutely! Dave |
Dave |
The only thing I want from Techspeed is a four nipple job on the Hydragas and maybe lowering knuckles, never had a quote from them as they never reply to my queries. Next time I'm in the UK I may sort it out if I have any cash. I have decent shocks, polly bushes and alternate tracking settings already but as they never reply I have been unable to get a quote out of them for what I still need. |
Tony Smith |
I tell you what, I love the cold weather cause my car looks really rather nice!! Was thinking about lowering knuckles, but don't need them in cold weather!!! You guys with knuckles, do you have your hydragas pumped up during the winter months? otherwise it must get very low???? Chris |
Chris George |
Tony, If your using email to contact Tech-Speed then forget it as you're right they don't reply. Virtually, unforgivable in this day and age of customer service but nevertheless true of what is a small race-preparation outfit that do respond exceptionally well by phone and face to face and have a fantastic offering for us F owners. Call either Roy or Marvin on +44 1926 632066. Dave |
Dave |
Right Go the ride height adjusted today £20 - cool Had it set to 360mm so its in rangerover mode but can always drop it a little when settled Anyway - drove it home and does feel a little better - but still skittish - while in the garage we checked shocks etc to ensure all was ok - which it appears to be - no leaks etc So anyway - bit dissapointed that it still oversteers -/and feels unstable Anyway - home and my K&N and splitter arrived - so went and fitted -Cooool K&N woooohooooooo And the splitter makes a big difference to the front "feel" of the car BUT Still have the wobble/unpredictable handling - So its got to be a shock absorber gone (doesnt bounce) or the need for those polybushes ! Suppose I may as well oder the bushes and try that - more money :( |
TONY |
Now the tracking to toe IN (+5 minutes) each front wheel and some more to the rear. :o) The guys there will see whether anything at the suspension has play and/or is worn ... if they are good. |
Dieter Koennecke |
I had the tracking reset on the front - made no difference - tyre wear is very bad front inside edges - both tyres - but bear in mind ride height was very low! I was told they cannot alter the rear ? rear tyre wear is perfect |
tony |
>I was told they cannot alter the rear ? rear tyre wear is perfect Err, mate, I wrote already the other day that you shouldn't believe those anones but the BBS regulars. ;) No problem to change the rear toe angle. And I'm very sure the trouble you described relates to the rear. See the adjustabel rear lower control arms. (german language WS manual copy: http://www.mgf-net.de/tracking/mgf_heck.htm A try in english language. http://www.mgf-net.de/tracking/ebspur.htm HTH Dieter PS. you need to spend a beer if I'm right :))) |
Dieter Koennecke |
Tony- check the ride height again (I suspect you may find that the ride height is now about 380 mm!!! ;o) It is the way that the suspension system works... Do bare in mind that the tracking is now going to be way off- the car is now riding at least an inch higher than before! Your shock absorber theory is a good one. Whilst the shocker may not be leaking, the mounting bushes (both upper and lower) could well be completely shot to pieces but not immediately obvious. See the condition of my cars damper bushes before I had the whole caboodle replaced at Techspeed- http://www.mgf.4mg.com/suspension_upgrades.htm Keep with it Tony- you're getting there! |
Rob Bell |
Tony wrote >>Still have the wobble/unpredictable handling AND >>tyre wear is very bad front inside edges - both tyres Don't you think time has come to replace your front tyre ? At this time, you're driving with correct settings but your front tyres are worn on half of the tread. Jerome |
Jérôme |
Agree Jerome - just wanted to get a feel for whats going on - if i change the tyres it will upset the feel - so best to fix the main problem and then get new tyes Rob - Thanks -I think i set new records for ride height - i need a ladder to get in :) hehe No seriously - I am sticking with it - I fitted the splitter and K&N - Nearly lost it in a hedge because of the handling - but had to boot it for the K&N noise - hehee Anyway - cars going back to the dealer to sort - it has warranty and while i dont mind doing a few things to get it sorted - now it is in the realms of expense i will let the dealer pay as i am so nice :) So it does tell you something - I have a car thats handles like a jellymould and yet I love it !!! BIG BIG Thanks to ALL for all your help - will let you know what has to be fixed when i know BTW - Dealer may have to give me the 3.0 GTO as a coutesy car :) - lol i will look like a pimp!!! Bloody fast one :) Probably end up with a metro :( |
tony |
Tony, once you have the height how you want it don't change it or let the dealer change it. I found that you have to go through a winter before the system stabilises. If you have it at 360 now it may drop down to 350 by the coldest winter day. By the time the weather gets warmer it should rise to around 355. The car will now stay somewhere between 355 and 350 constantly. As it is quite cold at the moment your car may not drop as far as mine did. But once the car has been through the complete temperature range it will remain stable. I have not changed the height on my car for over two years now and it has not changed at all. |
Tony Smith |
Hi Guys. My ride height is (or seems low) as it has been parked next to a realitivly newer F. Do you think this could be the reason why my cd player - which is mounted behind the drivers seat - keeps bouncing? I need to know as i'm due to get the suspension pumped up this weekend ( as I am in possesion of a hydrogas pump). |
Lister |
If the suspension is hard (which I guess it might be if it is very low) then you might have problems with CDs skipping. OTOH I am one of the few people with a CD player in an Elise & I don't think it has ever skipped. I believe most CDs have an adjustment screw somewhere - for adjusting depending on which way around the player is mounted (horizontal/vertical). Have you checked that? |
Dot |
yeah and have move the cd to the boot and back again - it hase been mounted the other way round for ease of acces though. Might turn it round so that the adjustment can be easily accessed. Cheers Dot. |
Lister |
Lister My ride height was 335 / 340mm -Way too low Upped to 360mm now - no difference in ride harshness! CDPLAYER There are generally two/four screw springs on the cd deck (will need to remove cover) and adjust slightly - mark with tipex where you started from so you can reset if you get it wrong |
tony |
Just a slight correction to Rob's first posting. The temp variation will in fact be 6mm per 10 degrees C change not 4mm as stated. A minor point and one that doesn't alter the overall situation with Tony's car having settled too low. Dot >>>you might have problems with CDs skipping<<< I wonder how Trophy owners get on?? Rog |
Roger Parker |
On Friday, a cold day in London, I noticed my car seemed to have dropped its ride height...there was a gap of say, the width of 2 fingers, between the top of the tyres and the wheel arch. I had more fluid added only a couple of months ago. Is this due to the cold or a leaking suspension system? How often should fluid be added as I've now had this done twice in the last year? I would add that there are a lot of road humps in the immediate vicinity. Any advice would be appreciated Cheers Nick |
Nick Sutton |
I believe the common opinion is that the system needs a full year to settle to a constant height The cold will affect height alot if you have had it adjusted recently Ideally this time of year the car should be about 350mm - measure from wheel centre to painted wheel arch(not to arch liner) vertically I think i am right in saying if your car is at 365mm and you want it down to 350mm - only drop it by a third - ie 5mm - as the height will settle quite alot lower than imeadiately set after a few hours ! Same aplies if you raise height - garage set mine to 360mm - its NOW 380mm - so to get mine back to about 350-355mm i have to reduce it by 10mm only and it should settle to 355mm -FUN HUH! |
TONY |
Ok - car went to dealers today Firstly we found one wheel bearing VERY loose - you could rattle it side to side with wheel on floor - not jacked up - must have missed this !! All bushes etc to be checked etc etc - further reports to follow for info One other thing i noticed - my ride height is way to high 380mm as said before - but when standing in front of the car you can physically see the wheels/tyres are biased to the outer edge so giving "outer" tyre wear! Now my car has been running a low ride height for 2000 miles and has eaten the inside treads So I took a look at the other MGFs there with low ride heights and sure enough the tyres are biased to the inner edge I have been told so many times that ride height doesnt affect tyre wheel alignment camber - but it is obvious that it does - you can see the difference in tyre alignment - certainly you can see the difference between my car at 380mm and a car at 330mm !!!! So make sure your ride heights are correct unless you want worn inner or outer tyres!!!! |
tony |
Quick question, If I have the 16" wheels fitted should the ride height still be 358mm. I would suspect that this is so, but my dealer says differently... Dealers who needs um...!!!! Cheers |
Danny Rivers |
Danny, Change your dealer! The ride height is measured from the centre of the wheel hub to the edge of the wheel arch above. So no matter what size wheels or tires you have the height is always the same. For the record the correct ride height is 368mm plus/minus 10mm measured at the front wheels only. Spyros |
Spyros Papageorghiou |
I have been thinking about changing dealers, loads of probs with them, but they also compensated me my upgraging my 15" wheels to 16" including bumpstop kit and tyre's... It also means that i have had to learn all about my car and send the dealer technical info.. Well got the info from the great people of this BB... (Thanks People)... Regards,,, |
Danny Rivers |
Tony, try a toe out setting for the front tyres of your car, this will stop the tyre wear I promice you. The height does affect camber but the problem is tracking. My car has been a 355mm for around two years and my tyres are fine. They used to wear down but changing to toe in 0 deg 5 min has cured this on my car. This is why it is so important that dealers leave the height alone as much as possible because the camber and other suspension geometry is suseptable to changes in height. Ignore MGR tracking settings, they are wrong, the more cynical may even see it as a revenue generating scheme for dealers. Where else can you sell new tyres at RRP. Most tyres are discounted at least 50% from RRP everywhere else. Personally I see it as a printing error in the original specs and that MGR are too chicken to admit it. |
Tony Smith |
Doh! Sorry Try a TOE IN in setting for the front of your car. Gawd, brain going.... |
Tony Smith |
This thread was discussed between 02/11/2001 and 19/11/2001
MG MGF Technical index
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