ok, just seen this thread
Well, I've been pre-occupied with being in Holland, refurbing my flat etc etc so hope you understand.
This is a very good and informative thread, and yes I've read all 9 pages, its taken a long time and I'm defo ready for breaky now so I'll make it quick.
Thought I'd add my 2p as I normally do
I'm not going to comment on the technical side because its already been explained and I understand 75% of it.
I currently have stock 15" rims on my rev 4 tubby and stock size tyres.
Not much has been said about tyre performance thus far, although Anna and Lauren touched upon it earlier.
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.
.
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When I first bought my tubby it had about 3mm of tread on all 4 good brand tyres, and on the second day of owning it I lost it on a roundabout without giving it much stick
(thankfully no damage!).
7 days later I did a huge wheelspin, unintentionally, whilst putting down
'a bit' of power in second at 20mph.
So, I went and got myself 4 new Goodyear F1s.
OMG, the difference was astounding, and to this day the
'roadholding' has been amazing in wet and dry and have not had even a slight bit of slippage.
I appreciate however Lauren's point about having really sticky tyres that prevent the
'real driving experience' of
'handling' and that if I did lose it, I'd probably lose it pretty badly.
Just wanted to say that tyre condition and brand is also extremely important to performance.
I never really go round corners particularly fast
(usually
) as admittedly I don't know the limit of the car, and have never done a track day.
So for me the F1s are superb.
In addition I would like to get some 17" rims
, of course for appearance and not performance.
I will keep the 15" for trackdays should I ever do one and get the 17s for general driving and
'roadholding'.
The rear of the wheel came into contact with the coilover spring seat/lock before i had even tightened the wheel nuts up 
