Ric,
165/70 will fit and doesn't look too bad. Anything bigger will really be
too much for a 3.5" rim and will look ridiculous (70 series).
185/60s can be made to fit with exactly the right spacing of the rim, but
you need at least a 5" rim and you would probably need a Panhard rod.
I use 165/65s on 5" rims but they are a little lower than even 145-13s.
I don't know if they would work on the stock rim.  I have seen them on
Rostyle wheels and they work.  If you don't mind an even shorter overall
gear ratio, you could try them.  
You can see pictures at http://students.washington.edu/ulix/Wheels.html
Ulix
On Wed, 24 Feb 1999, Ric Otte wrote:
> I have a 61-62 Sprite Mk II, and need to replace the tires.  I have the
> stock rims.  I could go with 155, but thought it might be nice to get a
> wider tire and smaller sidewall height.  I can't find any 155/70, although
> 165/70, 175/70, and 185/60  are available.  Does anybody know which of
> these tires will fit my car without modifying the fenders or going to
> offset springs?  Also, will they all fit on the stock rims?  I've been told
> that 185/60 will fit if I put spacers on the wheel studs to keep the tires
> away from the springs, but I can't believe they wouldn't then hit the rear
> fenders.  Also, is the performance difference between 155 tires and the
> other tires very noticable?
> 
> Thanks,
> 
> Ric Otte
> 
> 
> 
> ************************************
> Richard Otte
> Department of Philosophy
> University of California, Santa Cruz
> Santa Cruz, CA  95064
> ************************************
> 
> 
    Ulix                                       __/__,__      ___/__|\__  
..............................................(_o____o_)....<_O_____O_/...
                                              '67 Sprite     '74 X1/9
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