Landracing Forum

Tech Information => Technical Discussion => Topic started by: maj on August 07, 2013, 06:08:18 PM

Title: LSR tire growth revisited
Post by: maj on August 07, 2013, 06:08:18 PM

Hi all, trying to get a better idea of tire growth on d2284 and d2286

spent a lot of time searching and i find the MT growth table
but not much on the Goodyear

is 1" enough radial clearance, 2" too much ??

and will the 300mph tire see 320 ? 350? or will the regulations pull you up there anyway (think that was the dumb question)

Title: Re: LSR tire growth revisited
Post by: WOODY@DDLLC on August 08, 2013, 10:44:07 PM

Maj, tire growth is roughly linear, e.g. proportional to speed. If you allow .003" per mph radial growth plus some running clearance you should be good. Say 11.9" radius @ 200 mph. Get this radius from the inflated tire circumference! [C / 3.1416 / 2] 11.9"R + (200 * .003) = 11.9" + 0.6" = 12.5" R * 2 = 25" diameter. Add ~1" to that dia.! Hope this helps, sorry, cannot share anything more specific than that!

Title: Re: LSR tire growth revisited
Post by: maj on August 09, 2013, 12:07:23 AM

Thanks,
Trying to design front and rear suspension,bodywork, parachute fit and i definitely don't want to be caught short

Jon sent some tables possibly from you , and i found the MT  table in a search
I will host them  here for the next person to ask

Still interested to find out if the theory works in practice , i hear lots of comments about the tires "standing up" or the car feeling on tiptoes  at around 250mph
i would assume as the contact patch gets smaller

(http://img.photobucket.com/albums/v378/maj750/750%20and%201k%20stuff/LSRTireGrowth_zps6940c44a.jpg) (http://smg.photobucket.com/user/maj750/media/750%20and%201k%20stuff/LSRTireGrowth_zps6940c44a.jpg.html)

(http://img.photobucket.com/albums/v378/maj750/750%20and%201k%20stuff/MTTireGrowth1_zps382e1ba3.jpg) (http://smg.photobucket.com/user/maj750/media/750%20and%201k%20stuff/MTTireGrowth1_zps382e1ba3.jpg.html)