Hill Climb Tyres

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Kirklands 904
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Hill Climb Tyres

Post by Kirklands 904 »

As some of you may know my 904FF is having a 2.4S engine fitted over the winter. This will have at least 50% more power than the current 914 engine. This has led to my thinking about some proper wheels and tyres. I would prefer to stay with 15" and 70 section to fill the wheel arches but 17" and 55 section have nearly the same rolling radius. New wheels are a must but then what tyres to use. Hill climbs and sprints only so as soft as possible.

All advice welcomed provided it is physically possible!
Bill

904FF (Mike Bainbridge 2.4S engine and transmission)

I am hoping that I'll die before I grow up!
jwhillracer
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Re: Hill Climb Tyres

Post by jwhillracer »

Hi Bill,

Are you going to drive it on the road, or will the wheels and tyres be for hillclimbs only??

JW

PS - How's life South of the Border??!! :drunken:
Life's a single timed run with no practice....
1970 914/6 2.4E/Webers
1970 VW Beetle project
1972 911 Hillclimber 3.2 MFI. Part of the family for 30+ years!
2006 Hymer Merc Starline 630
2000 T4 Van LPG
2000 Golf V5 Estate GT (Greyhound Transport!)
Kirklands 904
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Re: Hill Climb Tyres

Post by Kirklands 904 »

Jonathon

It will only be used on hillclimbs etc.
Bill

904FF (Mike Bainbridge 2.4S engine and transmission)

I am hoping that I'll die before I grow up!
jwhillracer
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Re: Hill Climb Tyres

Post by jwhillracer »

The best are going to be Avon A15 race tyres with the Classic tread. I think 17's will look odd, (even on a fake 904!!) and the price will probably convince you to stay with 15" rims!

JW
Life's a single timed run with no practice....
1970 914/6 2.4E/Webers
1970 VW Beetle project
1972 911 Hillclimber 3.2 MFI. Part of the family for 30+ years!
2006 Hymer Merc Starline 630
2000 T4 Van LPG
2000 Golf V5 Estate GT (Greyhound Transport!)
redrobin911
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Re: Hill Climb Tyres

Post by redrobin911 »

The car will not handle or look right on 17's - I'd advise 15's and I'd go for AVON CR6ZZ tyres - great tyre and you'll also get it in the correct profile to suit the car.
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jwhillracer
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Re: Hill Climb Tyres

Post by jwhillracer »

Agreed the CR6ZZ's are a great tyre, I use them on our 914/6, which has the same sort of power as Bill is hoping for, but heavier than the 904FF. At Shelsley, one of Bill's favourite haunts, the CR6ZZ's are barely warm after the 1000 yards, whereas the A15 compound race tyres bite from the first corner. They can also be bought in a similar height (rolling radius). The limiting factor may be the grip generated being detrimental to Bill's 914 gearbox and shafts with the extra torque of a 2.4...............
At least with an MB built 2.4S installed, it ought to arrive at Shelsley running on all 6............... :roll: :)

Cheers!
JW
Life's a single timed run with no practice....
1970 914/6 2.4E/Webers
1970 VW Beetle project
1972 911 Hillclimber 3.2 MFI. Part of the family for 30+ years!
2006 Hymer Merc Starline 630
2000 T4 Van LPG
2000 Golf V5 Estate GT (Greyhound Transport!)
Kirklands 904
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Re: Hill Climb Tyres

Post by Kirklands 904 »

Avon looks like the choice either CR6ZZ or A15 in 185/70 x15 size. Anybody got any experince with Kuhmo Ecsta V70A soft?

It will be great to have more than three and a half cylinders next year. I must admit that they were all there at Bo'ness.
Bill

904FF (Mike Bainbridge 2.4S engine and transmission)

I am hoping that I'll die before I grow up!
911hillclimber
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Re: Hill Climb Tyres

Post by 911hillclimber »

Rather late to this thread, but those Kuhmos are utterly brilliant but only available with 50 section iirc?
Super grip even in the wet, road legal and on my 911 and the Impreza after it will last 3000 miles.

I've been through 3 sets, but now off the 1A and 1B MSA listing.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
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smallspeed
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Re: Hill Climb Tyres

Post by smallspeed »

V70's are the control tyre for the BMW championship - I've got some on my car, but not used them yet so can't really comment on their performance, but based on the lap times they're very effective.. the difference between the old classes C (V70A) and A (Slicks) is not that much on a track where cornering > acceleration - there's 3-5 seconds in it around Donington, but the class A cars are 300 (I think) bhp/ton vs. 260 bhp/ton.
Probably not as important to you as you'll want "instant grip" for hillclimbs, but they do appear to work very well!

Other tyres I've heard a lot of good things about recently are the Nankang AR1 and NS2-R, and the Federal 595rs - they've been gaining a lot of supporters in the track day crowd due to R888 prices going so stupidly high. Again possibly more suited to track than sprint/hillclimb, but they're available in a lot of sizes and different compounds, and are a reasonable price

Other end of the scale, the timeattack guys are using Pirelli Trofeo R as their control tyres in the clubman classes.. I believe you can get a fat discount if you go through the timeattack supplier (presumably Pirelli uk direct) and tell them you're planning on competing in timeattack next year. There was no requirement to be signed-up, up-front of receiving any discount.. I have no idea what sizes they're available in, but they must have a decent range as the cars competing in that series are wildly varying!
911hillclimber
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Re: Hill Climb Tyres

Post by 911hillclimber »

Smallspeed, do you know Richard Marsh, a young chef who has run in the BMW track series for some time in an old M3?
He and his father (David) are old time hill climbers who used to be in my class when I had the 911 and then the Impreza.
They come from near Shrewsbury.

On those soft Kuhmos, I was nearly FTD in my Impreza in the pouring rain at Loton, cannot stress how good they are despite a very shallow tread groove.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
smallspeed
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Re: Hill Climb Tyres

Post by smallspeed »

No, I don't know them directly, but do know the names - they were running in class A I think which is full-house M3's with slicks and big wings. I've not competed in the series, but have built my car around the regs (class c, which is 328's, 325's, and 330's with V70 tyres and limited wings). I hang out on the forums and things to pick-up their used parts and cast offs! :lol:

I've put the tyres on my car really to get a feel for them although I'll prob make a move to slicks and the clio-cup slicks are a perfect fit and dirt cheap (£15-25 each) to buy - a lot of the bigger teams seem to use them for one race or one quali session so they've got a lot of track-day life left in them :)
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