Wheel and tire sizes....what is too much?

[-Alex-]

I have been looking tire and wheel sizes for my mendeola front suspension equipped project. What is too much? Lets say that you have atleast mendeola or strut front suspension and good rear coilovers etc.

I'v seen on some beetles 215-235/40 tires at front and 245-275/35 at back, and i have considered 215/40R18 at front and 255/35R18 at back. Allthough 225/40R18 is much more common than 215/40.

How is to drive with 17 or 18" wheels?

I have been looking hollowspoke 993 turbo 18" wheels and speedline lookalike kerscher KRS wheels, which are not the heaviest wheels. And i would prefer 7,5 front and 9" rear.

This 1303 has 225/40R18 and 265/35R18 tires, rear wheels allthough look at least 10" wide..Looks pretty wide.

http://files.vau-max.de/images/2010/02/7ac333a68319b42d2013caa4a11fdef6.jpg

[Steve C]

Hi

I'm running either 8x18 & 18x10 with 215/40 & 255/35 or 8x18 & 18x9 with 225/40 & 255/35.

They say you can have too much tyre & wheel and it slow the car down, cant say I've noticed.

Steve

http://i1184.photobucket.com/albums/z328/1303Steve/SteveCarterOESC201220214_01_zpsbec24240.jpg~origin al (http://s1184.photobucket.com/user/1303Steve/media/SteveCarterOESC201220214_01_zpsbec24240.jpg.html)

http://i1184.photobucket.com/albums/z328/1303Steve/scwf_zps57b19415.jpg~original (http://s1184.photobucket.com/user/1303Steve/media/scwf_zps57b19415.jpg.html)

[Oval]

Lots of factors at play here... Beetles are light (especially in the nose) so only need a small tyre compared to other cars. I give myself a sore neck in motorsport with only 195/205 tyres (semi-slick) and in fact any wider (especially on the front) doesn't heat up sufficiently

[spannermanager]

Lots of factors at play here... Beetles are light (especially in the nose) so only need a small tyre compared to other cars. I give myself a sore neck in motorsport with only 195/205 tyres (semi-slick) and in fact any wider (especially on the front) doesn't heat up sufficiently
This is Bang on^^^^^^, :)but of course it's Motorsport where the wrong moves on tyres and brakes show up,, over braking and over trying is easy to do, brake temperature is tyre temperature, especially over the all important first few race laps where a properly set up Beetle can do a lot of damage to embarrass the others, too big on discs or calipers will mean no brake temperature to heat the hub/wheel and tyre core, it's even a problem in winter with the bog stock VW caliper on light cars of say 700 to 800 kg.
One advantage, to a point, of WIDER tyres on light cars, is you can run softer compounds at lower pressures, which on theory make it a quicker car, but again, it comes back to good brake temperature to heat the bigger tyre to best operating temperature.

[Oval]

Yep but in hill-climbs the car needs to 'work' from cold. Just like on the street, really...

Another mistake people make with beetles and wider tyres, especially Supers, is messing with offset and losing the lovely stable-under-brakes front

[judgie]

for hill climbs and sprints i run full wets on dry tarmac. they heat up very quickly and have lasted pretty well even doing 15 minute track sessions.
there 200/640/17 on a 7.5x17 rim. same size all round.
i used to run 8x15 and 9x15 with 240.580/16 and 200.580/15 so1 slicks and the car is faster on the 17 but much harsher.
when i first built the car it was on 7x16 and 8x16 with 245 45 and 205 50 road tyres. felt fine on the road but on the hill climbs understeered and would snap oversteer somthing i also found with the 15 wheels.
i dont get this with the 17 which in part i feel is down to the better balance of haveing the same size tyre front and rear.

[Crimson_Axe]

before I added the mendeola suspension I was running 8x15 and 10x15 but now I'll be running 9x18 and 13x18 i have wider fenders though

[Wally]

Hey Ken,
Nice to read from you again here!

For me, I thought 18" wasn't neccesary and I thought better allround performance could be had with a smaller, lighter tire and wheel combo so I switched to 17".

Don't have direct comparable results to share, but I feel I didn't loose any traction switching to a smaller front tire. Rear stayed 245 wide in 17" also and both on a 9J rim, but front size went down from 225/18 to 205/17 (from 7,5"/18 to 7"/17) without any traction loss (understeer) over the 225/18 combo :-)

Did save kilo's in unsprung weight going to 17" :-)

[spannermanager]

There is case for more rubber on the road, or footprint as it's called, were bigger is better and can offer more grip over a smaller footprint, but,,, there becomes a point where a much smaller tyre working at the proper temperature will be quicker by a significant margin,, the key with a Beetle is getting temperature into the tyre, any temperature is hard won as the tyre loads are comparatively low, brake caliper sizing is also key to core tyre temperature, my race car starts to lose grip as the fuel load, weight, comes off the front axle and tyre temperature drops, I run a soft compound on the right front and even that struggles on right hand tracks, most are. One advantage of wider tyres is a softer compound can be used and it needs less pressure to support itself, given it still needs a correct 'come in' pressure, if it's cold all the time, it's too big, no question.
Various cheats can be used on the front to generate temperature in cold weather, more camber and caster, the two are closely linked, more pressure to load given parts of the tyre, up on the crown for example, or on either shoulder, and then the toe settings.
It's harder to use extreme settings for longer dry Tarmac races, but it's common on shorter events, and you can ignore all this for road cars...

[Oval]

You can ignore all this for Hill climbs, too.. the car must 'work' from the start line with everything cold...

I've just gone from 15 to 14-inch wheels and saved more than a kilo per corner.. Yay!

[spannermanager]

You can ignore all this for Hill climbs, too.. the car must 'work' from the start line with everything cold...

I've just gone from 15 to 14-inch wheels and saved more than a kilo per corner.. Yay!

Good move Oval, going the right way, :)why not 13"? Even lighter with Kevlar tyres, Some wheel types foul the lower front ball joint I know, especially with drop spindles, a few German guys are onto them o.k, , and for circuit racing, gearing needs looking at to run 21/22" tyres.

[Steve C]

Hi

Doesn't having a smaller tyre diameter make for a smaller tyre footprint?

Steve

[spannermanager]

Good point Steve, and Theoretically yes, but the the other advantages outweigh it, temperature gain as above, is better than a cold but wider tyre, and you can go to a very wide tyre and wheel to gain back footprint without being absurdly heavy, very fast heating of the tyre and the brakes/ hubs/ tyre core from faster rotation, I lost traction with them at first, but gained it back mostly with tyre pressure experience and launch techniques, it was just adjusting to something different, I'm amazed at how quick minis launch on 10" wheels, tho many run 11" wide tyres, again, to get footprint area. Gearing is my problem on the circuits, the cure I want is a berg 5 speed 091:).. Not much really then...

[Crimson_Axe]

Hi Wally its been a while - Here is a quick look at my mendeola suspension with wheels/tires - the front part of the
suspension is 6 inches wider than mendeola normally makes them


http://www.shakaworld.com/Bug/frame/rearonlift.jpg

http://www.shakaworld.com/Bug/frame/sidenobody.jpg

http://www.shakaworld.com/Bug/frame/sidenobodyclose.jpg

http://www.shakaworld.com/Bug/frame/rearfrontview.jpg

http://www.shakaworld.com/Bug/frame/brakeaxle.jpg

Body test fit:

http://www.shakaworld.com/Bug/frame/sidebody.jpg

http://www.shakaworld.com/Bug/frame/rearbody.jpg

[-Alex-]

Chassis and drivetrain is ultra nice at your car:) No opinion at the body though....:lmao::lmao::lmao:

I think if you have 500+ hp, 255 and 315 street tiresizes on 18" wheels might be just spot on :) But, less should work also, lets say for example 225/275 combination, if you dont always drive corners agressively.

[SuperRSi]

Ken I think your car looks great! And it looks like Kevin has done an incredible job. Look forward to seeing it some day...

[-Alex-]

These are the wheels what i am looking, possibly painted the center to metallic grey:

http://www.kerscher-tuning.de/raeder/index.php?id=2

Lots of different sizes, possibly front 7,5" and rear 9". So far been looking michelin super sport / pilot sport, good year eagle F1 asymmetric 2, continental sportcontact 3/5, or bridgestone potenza S001.

215 and 205 at 18" sizes are hard to find at good brands, these are a lot moore to choose when tire is 225/40R18 or 215/45R17

http://www.mytyres.co.uk/cgi-bin/rshop.pl?dsco=110&cart_id=83509171.110.3179&sowigan=So&Breite=225&Quer=40&Felge=18&Speed=&Load=&kategorie=1&Marke=Bridgestone&ranzahl=4&tyre_for=&x_tyre_for=&Herst=Bridgestone&m_s=3&sort_by=brand&rsmFahrzeugart=ALL&filter_preis_bis=&filter_preis_von=&homologation=&search_tool=standard&Label=E-B-73-3&details=Ordern&typ=R-237042

http://www.mytyres.co.uk/cgi-bin/rshop.pl?dsco=110&cart_id=83509171.110.3179&sowigan=So&Breite=255&Quer=35&Felge=18&Speed=&kategorie=6&Marke=Michelin&ranzahl=4&tyre_for=&x_tyre_for=&Herst=Michelin&rsmFahrzeugart=ALL&search_tool=standard&Label=E-A-71-2&details=Ordern&typ=D-113205

http://www.mytyres.co.uk/cgi-bin/rshop.pl?dsco=110&cart_id=83509171.110.3179&sowigan=So&Breite=225&Quer=40&Felge=18&Speed=&Load=&kategorie=1&Marke=Goodyear&ranzahl=4&tyre_for=&x_tyre_for=&Herst=Goodyear&m_s=3&sort_by=brand&rsmFahrzeugart=ALL&filter_preis_bis=&filter_preis_von=&homologation=&search_tool=standard&Label=E-A-70-2&details=Ordern&typ=D-116082