Dunlop Tyre pressures - SR3 ?

[AlistairCoker]

I hav just changed from Avons to Dunlops. I was running the Avons at about 18psi cold (22ish hot). Should I run the Dunlops at the same pressures ?

[GeoffW]

Should be the same, if they're of the same construction (ie both radials or both crossplies), but no doubt someone will be along shortly to correct me

[Simon T]

25-28 psi hot on a hi down force spec car

Simon

[splitpin]

Simon T said:

25-28 psi hot on a hi down force spec car

Simon

Hi Simon

A while ago, quite a few laughed when I mentioned that Radical Safety Bulletin that recommended 28 Psi on HD PR06 & SR4 compared to the old 20 Psi for a non HD SR4 - most seemed to think it should be low 20s. As you are seriously bloody quick in one, do those significantly higher pressures suit the SR3 because of it's superior downforce?

Edited by splitpin on Saturday 29th August 20:54

[AlistairCoker]

I have standard spec downforce apart from a bi plane rear wing so I guess I should go for about 24 as a compromise.

[splitpin]

At least you guys in SR3s get a clue in the Owners Manual ....... 22 Psi becomes 24-28 Psi if it's 06 onwards higher downforce.

Us blokes in PR06 & SR4 still get told 20 Psi hot in our OMs, leaving us (well, me at least) to wonder what the hell that Safety Bulletin was all about. Not impressed. Hardly any difference between 20 & 28 Psi hot is there? Like you, I'm part the way there on updating to HD, bi-plane on, front conversion probably this winter), so I'm setting mine to about 22 Psi hot ........... seems OK but I feel a bit disappointed being left to guess.

[Simon T]

Guys tyre pressures are a really personal thing, It's the best way to fine tune your suspension, handling balance etc. Given that all all that is also relative to your suspension and aero settings plus driving style and preferences the only way to find what you need is to test.

Having run a Prosport before the SR3 I was sceptical about the higher pressures but having talked to the Dunlop guys and to the works team I gave it a try - works for me...

Simon

[ajh349]

I feel duped, I have been running 16psi cold (20psi hot) certainly didn't help when the rain fell before qualifing yesterday at Combe.

Will try higher settings next time.

[AlistairCoker]

I was at Snetterton yesterday and tried them at 25 hot to start with and then dropped them to 23, felt a bit better at 23ish to be honest but then the track temp was far hotter later in the day when I driopped them to 23 so maybe there was just more surface grip. Was a mixed Bike/Car day yesterday, great fun but the bikes make cars look pathetically slow down the straight, they were hitting 165 ish !

[splitpin]

ajh349 said:

I feel duped, I have been running 16psi cold (20psi hot) certainly didn't help when the rain fell before qualifing yesterday at Combe.

Will try higher settings next time.

'Duped' or not, damn fine performance at Castle Combe, so well done Alan.

I have no idea what tyre pressures you should be running; that Safety Bulletin didn't even mention Prosports, just PR06s!

All I would say is that Radical definitely told me that if my SR4 was the non HD Version, I should stick to 20Psi Hot.

Perhaps have a try on seeing how it feels upto about 24Psi Hot if the opportunity presents itself? I can see how an SR3 might run well on upto 28Psi Hot (much more downforce than a Prosport and even a PR06 come to that), but I reckon something on 13s would be much too lively and unforgiving ........ quite likely to be saying hi to either the gravel trap and/or a barrier.

[ajh349]

Many thanks, I really enjoyed the race, shame I bogged down at the start.

I may have an opportunity to get a test day in before the next event so will try higher settings. Need to be careful with understanding the results as I'm still "Ring Rusty".

Have attached a link to the in car video, really helps with evaluating my errors.

http://vimeo.com/6393975

[Simon T]

Another view of the same race

http://vimeo.com/6395387

Simon

[joesacco]

What fantastic driveing, very impreseed and the Video quality spot on, well done.