Amjad Posted January 27, 2012 Share Posted January 27, 2012 I know I'm thinking ahead a bit lol..but can anyone recommend what tyre pressures to run on my NA at Japfest? Particularly if you've driven at Castle?Tyres will be Uniroyal Rainsport 2s and the car will be stripped out (all seats bar driver's, parcel shelf, speakers, sub etc all gone)I've seen Taggy recommended 24psi rear 26psi front in general, but just wanted to check and there's less weight over the front wheels in an NA so if that makes any difference?Amjad Quote Link to post Share on other sites
Amjad Posted January 27, 2012 Author Share Posted January 27, 2012 ^ Quote Link to post Share on other sites
Amjad Posted January 27, 2012 Author Share Posted January 27, 2012 The only thing with doing that is it would be ideal on a full track day, but I'm only doing one session at Japfest I just want to try and see what would be best so I don't go out and have one rubbish session from the car not gripping. I previously used Toyo T1Rs on my GT at Donington, and in my first session slightly high tyre pressures (35psi) just would not grip. For the second session I dropped them (I didn't have a pump or anything so at a guess they were <30psi) and it handled a lot better!Online there's a lot of differing opinions as to whether to drop pressures for the Uniroyals (as they get hotter on track and the presure will go up) or to reduce pressures (reducing flex). Daily I run ~35psi to get better fuel economy, but in some corners I've found I get quite a lack of grip recently, but that may also be because of cold roads this time of year. So I'm kind of inclined to drop them for track?Thanks for the reply Quote Link to post Share on other sites
Amjad Posted January 28, 2012 Author Share Posted January 28, 2012 Anyone else have any advice? Quote Link to post Share on other sites
morgey Posted January 28, 2012 Share Posted January 28, 2012 could always have them filled up with nitrogen if your that bothered about changing pressures (it remains at a more constant pressure over changing temperatures), most tyre fitters can do it sts holburns etc. for a small cost. but obiously you would want to find out what pressure you would want to be running before having them filled. Quote Link to post Share on other sites
Amjad Posted January 28, 2012 Author Share Posted January 28, 2012 Don't wanna go that far haha. If no one has any idea I may just run what Taggy does (though he had R888s I think)Lowering pressure worked well on T1Rs but I've no idea what the pressures were and not sure whether Rainsports have a softer/stiffer sidewell Quote Link to post Share on other sites
Asad Posted January 29, 2012 Share Posted January 29, 2012 i say just get a set of track alloys with T1Rs (cheap and fun) and save the rainsports for the road (awesome tyre by the way wish i could use them), set them to roughly what you had last time and get a small compressor pump....only youll know what works for you everyone has different preferencesid never use my road tyres on track its a long way home esp with a bent rim/fucked tyres if something happens, just my personal prefferences find a cheap set of 15" rims (as ugly as you like it doesnt matter tbh) and get new shoes put on....scrub them in for about 500 miles then there ready for the track.....easily interchangeable with both your EP`s get one of the lads to mind your other wheels while your outnitrogens good, but you need it track side if your unsure on what pressures you want Quote Link to post Share on other sites
Amjad Posted January 29, 2012 Author Share Posted January 29, 2012 Hmm there's an idea. Don't tempt me to spend more than I need to An extra set of wheels would be cool with some Paradas or something but my parents would kill me taking up even more space in the garage hahaI think my Rainsports probably grip (and definitely wear) better than T1Rs which is why I want to use them on track. T1Rs were too soft and the sidewalls were melting last time! I think I'll just set em lower tbh and see how it goes. Castle Combe is only 40mins from home so not fussed on driving on the same tyres Quote Link to post Share on other sites
Amjad Posted January 30, 2012 Author Share Posted January 30, 2012 Fair do's to Uniroyal, they got back to me asking about the Rainsport pressures and only 2 days after I sent the email! "Thank you for your recent query. Pressures for track use a very much a personal decision. It is not uncommon for pressures to be dropped given the forces involved which invariably leads to expansion after several laps. The Uniroyal's are quite pressure sensitive, so it pays to be very accurate with regards to how you set them. In addition, they have quite a deep tread depth from new so pressure becomes even more critical as too low a pressure will lead to excessive block movement which can affect handling. Will you be driving to the circuit on the tyres? The pressures will need to be adjusted when they are stone cold so this would need to be done prior to leaving. How they react on the day will be down to the ambient temperature, track temperature and how hard you are pushing them. It will not be uncommon to see an increase of up to 10psi after several laps in warmer temperatures - particularly on such a short and technical circuit where braking and cornering forces are frequent and can be quite severe, depending on your ability and knowledge of the circuit of course. As such, you need to be very mindful if you are adjusting them when warm/hot to compensate for what handling issues you may find. Ultimately, you have to experiment to find the best pressures that work for you. Best regards,CraigProduct Support Engineer" Quote Link to post Share on other sites
Asad Posted January 30, 2012 Share Posted January 30, 2012 Up to yourself tbh, wont take up that much spacekumho never got back to me so thats excellent customer service, top marks to uniroyal! Quote Link to post Share on other sites
lukeEP82 Posted January 31, 2012 Share Posted January 31, 2012 Done a few track days and sprint race on r888 and believe 24psi is best. Quote Link to post Share on other sites
Amjad Posted February 9, 2012 Author Share Posted February 9, 2012 Up to yourself tbh, wont take up that much spacekumho never got back to me so thats excellent customer service, top marks to uniroyal!Yeah was really pleased they did! Done a few track days and sprint race on r888 and believe 24psi is best.Cheers dude! I think I'll be running a similar pressure to that if it's warm! Quote Link to post Share on other sites
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