hi all
I know nothing about wheels so I'd just like to ask if anyone knew what I should be looking for my current tyres says 215/35zr18 84w but I want to change for 16s or 17s
so what would the the "?" be for
16x? 17x?
thank you kindly for your help

 
I assume you are looking for a softer ride.
With an MR2 because of the rear weight bias, for balanced handling you need staggered sizes with wider rears than the fronts. (one inch difference is normal)
 
For normal street driving with 16" wheels the sizes often used are:
Front 16x6 or 16x7 with 205/45R16 tyre
Rear 16x7 or 16x8  with 225/45R16 tyre
 
for 17" wheels something similar would apply except that you would need 40 profile tyres to maintain the right rolling diameter.
 

I wouldn't bother with 16" wheels - they are just as bad if not worse than the stock 15s in terms of available tyres. I currently have 15" and 16" wheel sets so I know
 
For 17" wheels you are looking at 205/40 for the fronts and 225/40 rear for the closest fit to stock rolling radius.
 
HTH
Graham

215/40/17 is common for the front too, ergo a higher load rated tyre.
I use 235/40s on the rear, not beneficial to go any wider.

IN 17s the most common size widths are 8 for front and 9 for rear.
tyres for the above rims
front 215/40/R17
rear 245/40/R17
 
also dont forget the offset is also very important when selecting wheels/rims, get the offset wrong and the wheels can look like ****.
the most common offset for the above sized rims are +35
 
cheers

Re offset not just looks but also when its wrong tyres rub suspension or guards too. I use the above widths in +35 offset and its perfectly flush.

thanks guys for all the help 1 more thing will 16x7+35 front and 16x8+38 rear be good for daily driving? and what size tyres would be best thanks again

will 205/60r16 front tyres and 225/60r16 rear tyres be ok?

New front tire is at 111KPH (69MPH) when spinning at the old tire's 100KPH (62MPH) RPM.
New rear tire is at 112KPH (70MPH) when spinning at the old tire's 100KPH (62MPH) RPM.
Use this site to calculate wheel and tyre size http://mr2.gordaen.com/wt_calc.php

 
I'd swap the tyres over with the tyre sizes Redtarga listed. If you really want a +35 offset I'd get 3mm spacers on the rear or wait for a set of wheels with +35 offsets.

 
Wheel spacers are illegal.

 
 

phatjack

will 205/60r16 front tyres and 225/60r16 rear tyres be ok?

A bad really idea!!
Even if they would go without fouling, the car would handle like crap.
There are limited choices of brands available in the right sizes for 16's for an MR2 (even less available for 15's), but they are still available if you look for them.
You may have to mix brands F/R, but that's ok if tyres with similar specs are used.
As others have said there are more tyre choices around for 17's but they will ride harder. 
That's just the way it is with MR2's