WHY do bigger alloys mean worse handling?

[speed]

I usually change my wheels on my cars and to be honest it doesn't normally improve the handling, often its quite the oposite. On my m3 th estandard 18's were fine but the works rims i fitted just didn't feel as good. I think the worst was when i fitted 18's on my mk3 mr2, it handled horribly. Now i've got the mk2 and i'm pretty impressed with how it handles on the standard rims (15's i think). Even though 17's do look the part i think i might be tempted to stay with the 15's and just get them diamond cut for a better finish.

Whilst on the topic of handling i don't think i'd go for coilovers again, too harsh for the road and they do really need to be set up properly. The best combination i've found was standard shock's with eibach pro springs (do they do them for the mr2?)

[enji_benji]

yes they do! £140 direct from them (well was the price i got through work) and i'll get you the part number i have it at work.

Ben

[tomTRR]

Don't forget the tyres will also flex in the tread. So half worn tyres will generally grip better.

Also don't most tyres need a while to scrub in properly..

[Xmun7]

Hi guys, im in the process of converting my mk2 rev1 N/a into a Rev 3 Tubby, started her for the first time last fri , on the rev1 i was running 18s 7" with 215/35 fr and 225/35 rear. I am looking for a set of 17s currently looking at the Lenso D1R, 8" fr with a 32 offset and 9" rear with a 35 offset, tyres i had a set of Toyo's but am thinking of trying the Vredesteins, i have heard they are more grippy than the Toyos. I think i will go for 215/40 fr an 255/40 rear.

What do you guys think, should i have any rubbing issues? i dont want to use spacers do you think i would need? what about grip?

Btw i run KW V3 Coilovers

[John145]

Hi guys, not sure if this has been mentioned.

Why are radial tyres better than cross ply tyres in grip? Tyre wall flex.

Cross ply tyres are extremely stiff and when cornering the load transfer effect causes a stiff wheel to rotate about its contact patch centre. When the tyres flex the load transfer effect is absorbed, the roll does not happen and the footprint is maintained.

The same would be true of low profile tyres vs larger profile tyres, to a degree. Obviously 65+ profile jepodises performance due to overheating, but you would get a lot of communication through the wheel.

HTH.

Also, forgot to mention, people were talking about getting better 1/4 mile times with bigger wheels.

Makes complete sense, when you have plenty of power (which a lot of the turbo MR2s have!) its very easy to spin up the wheels from a launch. With a bigger wheel the torque acting on the road tyre interface is reduced allowing more engine power to be used before spinning the wheels.

[Mike 'MR2' McHugh]

Hi guys, not sure if this has been mentioned.

Why are radial tyres better than cross ply tyres in grip? Tyre wall flex.

Cross ply tyres are extremely stiff and when cornering the load transfer effect causes a stiff wheel to rotate about its contact patch centre. When the tyres flex the load transfer effect is absorbed, the roll does not happen and the footprint is maintained.

The same would be true of low profile tyres vs larger profile tyres, to a degree. Obviously 65+ profile jepodises performance due to overheating, but you would get a lot of communication through the wheel.

HTH.

Also, forgot to mention, people were talking about getting better 1/4 mile times with bigger wheels.

Makes complete sense, when you have plenty of power (which a lot of the turbo MR2s have!) its very easy to spin up the wheels from a launch. With a bigger wheel the torque acting on the road tyre interface is reduced allowing more engine power to be used before spinning the wheels.

Have you seen a graph for that John ??

[John145]

No comment!

[pbmr2]

wow what a read. every post (even the stupid ones) from start to finish.

would just like to say thank you to the people that put in the time and effort to try and spread the know how.

it was mentioned that the rev1 had a (front) adjustment that the later rev2+ models didn't have, just flicked back a couple of pages and didn't find it again..
what was this adjustment?

and could it be retrofitted to a rev2+ to add adjustment? i'm thinking of track setup rather than road.

[dantheman]

castor angle

[MR John]

Wow what a read......I'm seriously debating weather i buy the 18's with T1r's now

Thank's for the info by all users.

[swampy]

on the subject of needing/wanting extra grip=width on the back end 17" wheels realy do seem necassary and with the front not needing quite the same improvement a staggerd set up would be an obvious choice but i can not recall ever reading any reports of 15" front and 17"rear. this to me sounds in theory ideal for the suspension set up even if a bit sharp on the rear....but all said and done this is what i am considering for my super gt car which has a huge amount of rear and front downforce additions.

currently on 17" rotas f and r

guessing this would look kinda cool too.

[RobPhoboS]

Has anyone tried 15f 16r or 16f 17r ? (just curious)

I'm thinking about getting another set of wheels (mainly) for use on the road, purely down to having a wider tyre choice in a larger wheel (16" most likely).
I cannot afford to do this for a while but just doing some research for now.

I'm currently on the standard 15" wheels (205/50 & 225/50) using Toyo T1R's - 32psi/36psi
I'm also on BC Racing coilovers and whiteline anti-roll-bars.
It's currently just aligned neutrally but I'm due to book myself in with WIM asap.

[DB Mr2]

great read echo pbmr2's comments - thanks to all who put the effort in to let us in on all this info, will need to seriously think about sizes and offset when purchasing wheels!

[vmaxnick]

My tuppence worth; my 91 tubby was already running 17's when I got it. Shortly afterwards I bought the wife a 91 N/A on 14" rims and standard rubber.
I would agree with other posters about the feedback you get from the balloons but would have to say that in the dry, the 17's feel much more planted with way less flex.
I am into form rather than function and bought a set of He-youge Lexus discs and Willwood four pots which unavoidably called for 6mm spacers and longer wheel studs. The extra sprung weight has completly changed the handling from go-cart to barge.
I have kind of got used to it now though and find the handling although quirky, a bit of a giggle!
I wouldn't recommend the mods if you want to corner fast though but if it's a look you want, it is just so sweet to see those discs and calipers filling the wheels.
(Brakings no better either, work that one out!)

[MR2 Rich]

Think the standard alloys look best so will stick to them if they are best for handling aswell

[Marf]

It's just a shame that the tyre choices available for the stock 15" setup are so limited.

[MR2 Rich]

Very true can only find falkens or toyos if you want a matching set.

[ads]

Must have spent days rattling my brain sussing my next move for 15s

I want to stay with 15" but really at my wits end with only Toyos or Falkens left in standard size .. only saving grace is Falkens handle progressively.


Looking on Camskill, TBH the tyres I really want are trackday - Yoko AD08 but only available in 205/50 rears and I'd have to drop to something like 185/55 fronts.

However, trackday tyres do tend to have a wider footprint for a given size than 'standard' tyres like Falken or T1R - also although they're not as wide as standard size they are grippier .

Sidewalls will be much stiffer on trackday tyres , responsive but maybe not so good for handling.

Opinions please?

[Marf]

Go to a 16x7/8 setup

[ads]

Go to a 16x7/8 setup

Yes finally had to do exactly that. Will have cheap tyres for now as I only so a few miles over winter, then hopefully onto AD08s or perhaps Federal RS-R or Uniroyal rainsport 3 .

Whole new world of choice now opened up