real performance of a real haynes roadster

[baz-r]

just a bit of an update for you all out there as I know I have not been in of late.

just wanted to share some real life performance of my car that I have been devloping over the last few years on road, track and hillclimbing

car is 505kg dry and empty and 705kg wet and me sat in it (325F- 380R)

top speed at castle coombe stright 118mph (5th)

2 people 0-65mph on warm toyo r888 3.42 secs (no wheel spin)

best time at wiscombe park hillclimb (1000 yards or 914 metres average gradient is 1 in 13.6 and the steepest section is at the Martini Hairpin where it is 1 in 6.9.)
dry 46.51secs semi slicks, 48.50 std road tyres
wet 50.12 std road tyres

I still run the same 1800cc zetec silvertop on fuel inj throttle bodies but now run piper fast road cams in a ported head (was 165.1bhp @7100 before porting)
tall first ratio kit in type9 now and 3.92 lsd diff
toyo r888 med on 15" pro race 1.2 wheels all 20psi road and 16-18psi comp
350lb front springs and 275lb rears (DONT recomend for open diff and normal tyres!)
2.9 turn rack

dont waste time fitting rear discs or bigger than std front discs just use vented fronts and try and reduce unsprung mass as much as possible

[CTWV50]

Good info there. And some good advise!

That first gear and dif ratio must be a hell of a ride!

[baz-r]

1st was useless at a reduction of 3.9;1 even with my old 3.6 diff you could pull away in 2nd no problem

1st is now 2.9;1 ish and can get to about 40 in it befor the limiter cuts in at 7200 (datalog says its hitting 7600 )

70mph and im pulling 4000rpm in 5th so its all faily close feeling with the 1st kit and low diff now still wish i went full cr semi helical kit but its a grand

[baz-r]

240lb springs is what i would go for with open diff and road tyres and road use and the minimum damping you can get away with

i had my gaz ones made with fine ajusters that have twice the clicks (8 clicks a turn iirc) think i was fully out and then 6 front and 3-4 rear its all so light you need naff all

[alga]

Baz, do you have any advice about tyres? I've almost worn out my first set of r888's, and last year I got a set of budget Syron "semislicks", which were actually pretty hard. I guess ideally I want a set of soft semislicks for autoslalom/autotest competitions and something cheaper, and better in the wet for general driving and slalom practice. Are r888 still be best tradeoff? Maybe the new r888r model is worth a look? Maybe a compromise like Advan Neova AD08R would tick all the boxes for street and competition?

[baz-r]

i have 2 sets of wheels and tyres, i use my toyo R888 gg compound (med) for competition and summer use the car is so light tyres don't heat up or wear like they would on a production car

i have no experince with the new toyo R888R as its so new and untested.

a tip i found when tyre hunting is to look at the tread wear rating on the sidewall this way you can compare tyre softness between tyre makers and their compounds

high number (hard) = long lasting, lower grip, low rolling resistance, hard to get hot
low number (soft) = quick wearing, higher grip, higher rolling resistance, easy to get hot and sticky

normal use road tyres = 300-250
sports road tyres = 280-180 (ns2r norm = 180)
soft sports road tyres = 150-110 (ns2r soft =110)
med compound track day tyres = aprox 100 (toyo 888 GG/med)
soft compuund track day tyres = approx 60 (yokohama soft)
super soft track day tyres = aprox 20-40 (khumo super soft)