35psi tyre Pressures

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I know this has been covered before in various threads. All my other performance cars have had pressures of 33psi + and I was a little doubtful over having my fronts tyres set at 29psi. So I set all my tyres to 35psi the other day and was amazed at the difference it made to the total overall feel of the car. The steering is more positive and it rides over bumps with ease! I was suprised that Skoda did not set the tyre pressures at 35psi, the same as the Golf Gti on the same chassis. The car really does need higher pressures in them, as I feel 29psi is far too soft for car of this size and weight. Plus if you are cornering hard or in fact braking hard. The tyre walls will be soft, wobble and unsettle the balance of the car. I for one, will be keeping my car set at this pressure from now on.

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Manufacturers typically recommend lower pressures to improve the ride quality (i.e. make it more comfortable). They are not the ones who pay for the prematurely worn out tyres.

The rule is always to follow the advice of a tyre specialist rather than what the car manufacturer says and generally tyre specialists recommend pressures noticeably harder than the factory.

Just out of interest my vRS was delivered new with 36psi all round from the dealer.

Edited by K1W1

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I thought the VRS pressure was 32psi or 2.2Bar?

I've never had unusual tyre wear with all 4 wheels at that so I've assumed it's right.

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It is certainly 2.2 BAR for the 1.8TSi all round unless on full load (5 people plus full boot of suitcases) - then the rears only supposed to go up a bit.

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Even for my Elegance, on 17" rims,the recommended pressures are a minimum of 2.1bar F (30.5psi) and 2.2 bar R (32psi). I use that unless heavily laden for camping etc.

From memory, 35psi must be about the maximum recommended, but pressures are only given in bar on the sticker.

I have driven on higher pressures in the past but I prefer to get even wear across the tread which the current setting seems to be giving.

Watch out for variations in ambient temperature affecting the tyre pressures, the recent -6°C or so took a few psi out.

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I use 35psi all round aswell

Definate difference and better feel for the car

Carl :thumbup:

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What's the deal with having slightly higher pressure at the back?

I'm sure I read that it's best to put 33psi in the rears and 32psi in the fronts but I can't remember why. Is it to do with the Octy being a bit tail heavy due to the boot overhang? :S

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All the cars I've had over 45 years motoring have had the manufacturers recommended tyre pressures and have given reasonable even wear across the full tread ( with a little corner rounding due to earlier youthful exuberance of going round corners too fast). I've never had to use budget brand tyres and have always felt that the most important thing between you and the road are the tyres.

High speed front tyre blow-outs ( 90mph in MK2 Jag.- before the 70 limit !) tend to stay in your memory !

Raising pressures above the recommended will give a lighter feel to the steering and may feel "more direct" but the ulimate grip will be reduced.

The manufacturer's recommended pressures are based on normal motoring with different loads . Obviously a particular car may not fall in exactly with the loads specified but will not be too far from them using common sense

My old air-cooled Beetle had the recommended front tyre pressures of 18 lbs/sq.ins. !

Many years ago it used to be that the recommended tyre pressures were increased by 1 to 2 lb/sq.ins. for motorway driving as the recommended pressures were for non-motorway use. But obviously this is not so today .

Edited by vwcabriolet1971

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Running 225/40/R18's i went from 32psi in the fronts to 35psi, then 32 psi in the rears.

I must say it sticks rather well, the turn in was improved considerably by just upping the front tyres by 2 psi.

Edited by Browny_37

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My tyres (205/60/R15) were set at 30/29 (front/rear) from the factory/dealer upon delivery, which is exactly the recommended pressures for light loading.

Interestingly, the recommended pressures for fully loaded vehicle are 35/46psi (46psi for the rears seems high to me).

Anyway, I was thinking of increasing mine a little to see if it helps handling - turn in on corners feels a little wishy washy so I'm hoping it might sharpen up a bit.

I thought I might try 36/35psi (front/rear) as a starting point.

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Always put 0.3bar more on the fully loaded spec.

2.7 (39psi) front and 3.3 (48psi) rear.

And even with these pressures it rubbed the sides on the Nürburgring GP track.

Gives me a better mileage too.

But I am doing a lot of (fast) autobahnmileage. Hasnt been negative on the wear of the tyres up to now (one set of Continental CS2,one set of Sport Maxx, one set of Conti TS810 winters and one set of Winter 3D winters), means no exessive wear in the middle due to the higher pressures.

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The recommended tyre pressures for a Mk2 vRS on 18" wheels are:-

Normal Laden - 2.0/2.1 (29/31)

Fully Laden - 2.3/3.0 (34/45)

Obviously putting in more air than necessary will have a perceived effect have making the car feel easier to drive but, as you can guess, that's only because there's less rubber contact with the road!

Following on from that, why Skoda don't fit 15" wheels with narrow tyres on this car - maybe something to do with grip do you think? B)

Remember when the snow was here a few weeks ago and how your steering felt very light?

I can't recollect anyone saying pump up your tyres to get better traction - if anything you'd need to remove air to get more rubber contact.

The recommended pressures are there for a reason - but then again, maybe you know better then Skoda, Michelin, Dunlop etc etc.

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Hi John

you forgot one thing. It is not the straightline grip that counts, it is the cornering grip that counts.

And with lower pressures your tyres will walk and you will end up driving on the side walls if the cornering speeds are high.

Higher pressures (to a certain amount) will keep the tyre better in its original form when cornering and so will give you more grip.

And in a straight line, I dont need so much grip. Here the higher pressure will make the difference in mileage.

I dont know things better than the tyre companies, but have my experience (also in track driving and autosport).

The recommended pressures are standards, it doesnt mean that every tyre in that size works best with these tyres. (there are discrepancies in different tyre makes, although little the companies often give their own recommendations)

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Hi John

you forgot one thing. It is not the straightline grip that counts, it is the cornering grip that counts.

And with lower pressures your tyres will walk and you will end up driving on the side walls if the cornering speeds are high.

Higher pressures (to a certain amount) will keep the tyre better in its original form when cornering and so will give you more grip.

And in a straight line, I dont need so much grip. Here the higher pressure will make the difference in mileage.

I dont know things better than the tyre companies, but have my experience (also in track driving and autosport).

The recommended pressures are standards, it doesnt mean that every tyre in that size works best with these tyres. (there are discrepancies in different tyre makes, although little the companies often give their own recommendations)

I agree with you in parts and appreciate that there should be a few extra psi in the tyres when sustained high speeds are being done. In general terms I seem to be going forwards and not cornering so would like my grip to be spot on in that direction. Your driving style would probably dictate otherwise.

Granted there will be extra mpg if there's extra psi but as a consequential downside there's also less grip.

In amongst all this the car manufacturer decides what is the best generic pressure is.

Just as an aside, would you put extra air in your winter tyres if you were driving in snow?

[Devils Advocate mode off]

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Yep, modern wintertyres use higher pressures. Only under extreme conditions with lots of loose snow, it would be wise to let some pressure off.

But under 99.9% of the driving conditions it will be better to have higher pressures (I do drive them with 2.7 fr/ 3.3 rr).

In a straight line you dont need grip, at least not that much. More important is that the tyre keeps it form under braking. This does it better when the pressure is higher. (in this case the compound can do its work while gripping and the carcass wont deform. )

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Just as an aside, would you put extra air in your winter tyres if you were driving in snow?

Could that not apply both ways though?

You could decrease pressure for low friction surfaces (snow) -- because the trade offs between grip, fuel economy, tyre wear etc. hit a sweet spot with a lower pressure in snow / slush.

Does that mean that when the surface is higher friction (say wet road instead of snow) the best trade off point between grip and all the other factors would be at a slightly higher pressure? E.g. we don't need as much grip now there's a higher friction road surface, so we can trade some grip to improve fuel economy?

If i was a manufacturer, and i don't want to produce a complex table of tyre pressures to confuse my customers, how would i choose what tyre pressure to tell them? Tell the customer the lower pressure for snow, to aid for the times the customer drives in severe conditions?

But that would come at the cost of some CO2 ratings which, as a manufacturer would not be attractive. I could tell them a high pressure to improve CO2 ratings but the car would probably get slated by clueless journo's for being skittish in the wet == sales disaster.

Does anyone have inside information on how the manufacturers choose? I know they don't always get it right -- some ford 4x4s were toppling over because of excessively low pressures recommended by ford. I think low tyre pressure was partly to blame for the original Merc A-class that toppled too. I'm thinking they'd choose to recommend a pressure smack bang in the middle?

I've heard of the 10% rule -- ignore the car manufacturers recommendations, look at the tyre sidewall for max psi that particular tyre can handle, then take off 10%. From there you're supposed to be zoned in on a good position to find the optimal pressure quickly (45psi max == start testing at 40.5psi) -- although i'm guessing that probably assumes dry pavement, quality tyres and a whole range of over things i don't know about.

Interesting thread :thumbup:

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Another point - it would seem that the reading you get on your pressure gauge depends on how cold that day is before you set off. You are supposed to take the reading with the car "cold", naturally, and if you test them on a freezing cold morning, then again the next day when it is nice and warm (as if!) the reading will be higher without putting any more air in because the air inside the tyre is also warmer and expanded more.

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Does anyone have inside information on how the manufacturers choose? I know they don't always get it right -- some ford 4x4s were toppling over because of excessively low pressures recommended by ford. I think low tyre pressure was partly to blame for the original Merc A-class that toppled too. I'm thinking they'd choose to recommend a pressure smack bang in the middle?

No inside information, but I did read that manufacturers simply haven't bothered changing their recommendations from years ago and technology has moved on so the recommendations may not be as, how shall we say, measured as perhaps they should. Could be true, could be just Internet rumour.

I've heard of the 10% rule -- ignore the car manufacturers recommendations, look at the tyre sidewall for max psi that particular tyre can handle, then take off 10%. From there you're supposed to be zoned in on a good position to find the optimal pressure quickly (45psi max == start testing at 40.5psi) -- although i'm guessing that probably assumes dry pavement, quality tyres and a whole range of over things i don't know about.

I've read the 10% rule too. My tyres have a max of 51psi so that would give 46psi which seems very high to me, as someone who has always run tyres around the 30psi mark.

I've just increased mine from 30/29 to 36/35 front/rear and went for a quick drive (15 mile round trip). I felt the turn in was a little more positive, and the ride a little harder but I'm on 15" rims so I have plenty of tyre to soften the ride a little. Mind you, I have no idea how accurate my gauge is so I might just have been under pressure to start with and I've increased to the recommended pressures if my gauge were 6psi out.

Edited by Phil_P

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Cold check is essential. After a good stint on the autobahn, the tyres will be far to warm.

I always check/fill my tyres at home with an approved gauge (for my compressor) in the morning. Even if the car stood in the sun for a while, you will get different readings (mostly even one side higher (sunny side) as the other).

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The recommended tyre pressures for a Mk2 vRS on 18" wheels are:-

Normal Laden - 2.0/2.1 (29/31)

Fully Laden - 2.3/3.0 (34/45)

So I was right then. They should have a little more pressure in the rears?

I still think 45psi on even a fully laden car is a bit excessive :S

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