MG4 tyre pressures - comfort and economy

[BugEyed]

About the only thing correct about our PDI was the tyre pressures that were spot on. After a few miles I'm now changing them in an attempt to improve the dire economy of our SR which is averaging under 4.0 over 1,600 miles of a mixture of motorway at 60-65 and local roads at commuting speeds rarely exceeding 50 MPH. Edited to add this is with the heating at 18 and fan at 1 - I find it mists up with the ventilation control fully off.

I have raised the fronts to 38 psi and the rears to 41psi with a notable improvement in the feel of the rear of the car but at the expense of more understeer at the front. On the first drive it has improved the figures by about 0.3 miles/kWh but whether that's a long term result or a one off is hard to know - it was milder this morning at 15C.

Has anyone else tried adjusting their tyre pressures, and if so with what results?

Alternatively, should I expect the SR to be this poor and is the LR better for some reason such as the battery technology, the gearing, the active grille etc? Or is my car just a lemon?

 

[siteguru]

Bear in mind that tyre pressure is relative to temperature. Usual guidance is that the recommended pressures are based on cold tyres and an ambient temperature of 20°C.

The manual says (as I'm sure you know) 37 psi for the fronts and also the rears, and 41 psi on the rears when fully loaded.

 

[BugEyed]

Understood. Hence the baby steps - ride/handling wise it is quite sensitive to the changes, but i'm pretty sure that there's something wrong with the economy.

 

[tsedge]

Is under 4.0 dire for winter with that mix? Doesn’t sound too bad to me.

 

[BugEyed]

It's in the last four weeks of unseasonably warm but often wet weather. It seems bad to me as previous EVs have averaged 4.4 - 4.6 miles/kWh long term (so a full annual mix of weather) and others are regularly posting higher figures on here and faceache.

 

[tsedge]

It's in the last four weeks of unseasonably warm but often wet weather. It seems bad to me as previous EVs have averaged 4.4 - 4.6 miles/kWh long term (so a full annual mix of weather) and others are regularly posting higher figures on here and faceache.

Understood. I have seem some people posting above 4 but also plenty between 3.5-4. Of course it is driving style dependent too. What I have gathered is that the MG4 is average at best on efficiency.

 

[MuzGB1970]

Coming from 3 years in a hybrid I tend to add 1-2psi to the recommended tyre pressures, which does definitely help with economy. Just remember not to go too far over and you will also need to check and adjust frequently as conditions change. As for economy on my Trophy, I'm averaging 3.7 miles/kWh after about 1,000 miles of very mixed motoring. I'm reasonably happy with this for this time of year. I have the climate set at 21 degrees and Auto, giving me a usable maximum range of about 220-230 miles, which is what I expected before I got the car. 270 miles WLTP may just about be achievable in the summer but you won't get close at any other time of the year. I did a charge to 100% yesterday and the GOM said 243 miles range.

 

[tsedge]

Coming from 3 years in a hybrid I tend to add 1-2psi to the recommended tyre pressures, which does definitely help with economy. Just remember not to go too far over and you will also need to check and adjust frequently as conditions change. As for economy on my Trophy, I'm averaging 3.7 miles/kWh after about 1,000 miles of very mixed motoring. I'm reasonably happy with this for this time of year. I have the climate set at 21 degrees and Auto, giving me a usable maximum range of about 220-230 miles, which is what I expected before I got the car. 270 miles WLTP may just about be achievable in the summer but you won't get close at any other time of the year. I did a charge to 100% yesterday and the GOM said 243 miles range.

Yes, that is what I was expecting.

But, OTOH, if Bug Eyed is a particularly efficient driver, it should be possible to get more.

 

[BugEyed]

after about 1,000 miles of very mixed motoring.

When you say "mixed" do you mean different road types/condition or different attitudes towards economy/fun? Mine has all been being very careful, not having fun.

 

[MuzGB1970]

When you say "mixed" do you mean different road types/condition or different attitudes towards economy/fun? Mine has all been being very careful, not having fun.

When I say mixed I mean, mixed range from lots of very short (bad for economy) to several longer (50-60 miles) journeys, with a sprinkling of distances in between. Mostly cruise control on set at the road speed, but also some fun harder acceleration to see what it will do. I'm not one for high speed, I left that a long time ago in my youth, so tend to go about 65mph on the motorway.

Before I got the car I said I would treat it like a regular car, not make too many changes to maximise the range, that's what I've been doing.

Forgot to say that pretty much all my motoring has been with NORMAL drive mode and regen 3. Haven't tried SPORT or SNOW at all, used ECON for one trip (around 15 miles) and saw about 6 miles/kWh but didn't like the climate on economy.

 

[Torryhun]

Bear in mind that tyre pressure is relative to temperature. Usual guidance is that the recommended pressures are based on cold tyres and an ambient temperature of 20°C.

The manual says (as I'm sure you know) 37 psi for the fronts and also the rears, and 41 psi on the rears when fully loaded.

I've been advised to fill tyres with Nitrogen, pressure does not fluctuate as much, lasts longer than air due to less leakage.

 

[BugEyed]

Excellent marketing for a premium service. Do you really notice the difference outside of F1?

 

[Torryhun]

Excellent marketing for a premium service. Do you really notice the difference outside of F1?

Only cost £5 to find out at Costco fitting bay

 

[WalkingBootWeather]

I've been advised to fill tyres with Nitrogen,

Now you're laughing....

 

[PCR]

Always remember air is 78% nitrogen.

 

[tsedge]

Like changing your brake fluid every 5 minutes, or recharging your a/c when it doesn’t need it, just another way to make money. Nitrogen makes no real difference for road cars.

 

[TommySJ]

How does you change tyre pressure from PSI to BAR.. anny idears

 

[Matt x power]

I just put 37 psi all round

 

[siteguru]

How does you change tyre pressure from PSI to BAR.. anny idears

In what sense? In the car display? Converting between Bar and psi?

For the first option (car display) then only changing from Metric to Imperial may do that ... but that would also change things to show in Miles rather than Kilometres.

For the latter:

bar to psi - Google Search

 

[SimonMGEV]

I put 36 PSI all round but that is on all my cross climate 2 tyres. My original Bridgestone tyres were inflated all to 37 PSI