accord 97, tyre preasure ?

[accord97]

I have an accord97 with 205/60 tyres fitted.

I normally inflate tyres to 32psi, however after getting my tyres changed at the tyre shop them came back with 37psi.

I rang another place and asked what they recommend, and they said 34psi front and back.

So i'm a bit confused. Any ideas ?

Thanks

[JohnL]

Are these tyres on a 5.5J rim, or something wider? I don't know the standard rim width for a 97 Accord, but I think it's probably 5.5, which is a very narrow rim for a 205 tyre. If the rim is too narrow for the tyre width then the tyre will become laterally unstable. This is because the sidewalls will behave as if they were effectively softer (than with a wider rim), and steering response and handling will probably suffer, but you will get a smoother ride quality.

IMO you'd be better off with the standard 195 tyre width (which is still a fairly wide tyre for a 5.5 rim), or even a 185/65 which better suits the rim width, even if you do go up in aspect ratio (which isn't as bad as it sounds because the sidewalls will still be the same 'height' only the tread will be narrower, and you benefit because the sidewalls will be less angled inward toward the rim). A problem with 185/65 tyres is that the selection in this size is poor, and largely restricted to very pedestrian rubber.

As to pressure, it depends on the particular tyre and how that tyre works on a particular car. It also depends on what you want the tyre to do and not to do. The higher the pressure the better the steering response is likely to be (up to a point of diminishing return, and beyond that maybe going backward).

However, assuming higher pressure does increase response (it probably will), it may (or may not) increase it at the expense of ultimate grip on smooth roads, or ultimate grip on rough roads (these not being the same, i.e. with higher pressure you may increase grip on smooth roads, but lose grip on rough roads at the same pressure).

You may find an increase in both response and grip at higher pressure, but you may find that the car becomes too harsh for your comfort or taste at a pressure giving optimim grip and / or response. It's also possible that higher pressure may increase wear, but equally possible that wear may decrease or be unaffected.

I would think 32psi likely to be on the low side, but it depends. Air is cheap, pump them up to what you usually use and see if you like it better, if not then let air out. If you like the higher pressure you might try even higher, and higher, until you don't like it any more and back it off to a lower pressure. You really need to experiment with tyre pressure, what works for a given tyre may not work for a different tyre (even when fitted to the same car), and then there is personal preference re the compromise between handling / grip / comfort.

Tyres are safe up to the max inflation pressure marked on the sidewall, don't be afraid of trying them up to this pressure, though it's likely that this will be too high. The car manufacturers almost universally reccomend pressures that are quite low, primarily to promote a refined level of NVH (noise, vibration, harshness). The max reccomended pressure is a cold setting, the pressure may rise above this when they warm up, but this is OK.

On my car (91 CB7 Accord), I have cheapo 195/60/15, different brands front to rear, and my pressures are 38 front and 45 rear. This is just what works for me with those particular tyres (my personal bias is for optimum steering response while maintaning good grip, or as good as the particular tyre can give). The rears require a high pressure because they have a very soft sidewall and won't behave unless at a high pressure (Falken Ziex 329 are NOT a good tyre!).

A rule of thumb that can be used with some scepticism as a starting point for experimentation is; inflate to 10% below the max pressure on the sidewall. After a lot of experimentation this is very close to where my pressures have ended up. The max reccomended pressure on the sidewall will probably be either 44psi or 51psi.

PS Check pressures regularly, I do it at least twice week. Cold pressure will vary significantly depending on ambient temperatures, the same amount of air in the tyres in winter will be at a lower 'cold' pressure than they will be in summer. Get a good quality pressure guage and use only that one, guages can vary a lot, and servo guages are worst of all because they can vary hugely one to another. Always set pressure with cold tyres. A tyre that has been sitting in the sun will read higher than the others if they have not. If your car has been sitting in the sun then two tyres will be warmer than the other two and be at higher pressure (maybe up to 2psi), so if you pump up the others to match, when they all warm up to the same temp on a run or cool down you'll still have unmatched pressures.

[SiReal]

I dont think 5 PSi make that big a different to day to day driving. Fronts i usually put 35 ish. rears 32 ish.

JohnL - u write essays everytime haha ;)

[shadou]

I think you read too much in to this for a road/daily use car, I would go 34-36 front and maybe 32-35 rears (PSI)

[aaronng]

Use what is comfortable to you, but make sure it is above 32psi (or the minimum on your tyre pressure sticker) but below 38psi (check your tyre sidewall on the max pressure too).

[JohnL]

I dont think 5 PSi make that big a different to day to day driving. Fronts i usually put 35 ish. rears 32 ish.

Not my experience. I've found 5psi can make a very noticable difference, but probably not if just driving around the corner to the shops.



JohnL - u write essays everytime haha ;)

Not my intention. I just start typing, and keep on thinking of things to say!