Upgrading to 1 inch timing belt?

[droptop]

My spider will be five years in my possession this coming Spring and despite covering less than 6,000 miles since I recomissioned it, I recon I should replace the timing belt due to its' very age.
I've seen that you can upgrade to a 1 inch belt which seems to be more resilliant and I'm wondering who here has done it?
I don't want to bite off more than I can chew or find I need some hard-to-find pulleys and the parts that concern me the most is the front crankshaft vee belt pulley and whether or not the wider belt would rub against the back of it and if the tensioner is wide enough without stripping things back beforehand..
With any of my projects, I like to have all the bits to hand before I start so any advice would be welcome.
In other words, I'm a lazy sod that likes to do things the easy way!
Thanks

[rossocorsa]

I think it is a straight fit on a beta but guy croft will confirm, give him a call he doesn't bite! Also only source for the belt that I am aware of too.

[Thotos]

My 131 with a Guy Croft engine has the 1 inch belt and I seem to remember Mr Croft telling me that you can't fit the 1 inch belt to any set of camshaft pulleys. Some pulleys are plastic, some are aluminium some have belt stops at the front some have them at the back and some have them both front and back. Look on Guy Croft's website or give him a call. Or fit a heavy duty 3/4 inch belt ;-) http://www.needforspeed.co.uk/pages/sbv_pl.asp?Vehicle=FT13101&PartType=CAM08

[droptop]

My 131 with a Guy Croft engine has the 1 inch belt and I seem to remember Mr Croft telling me that you can't fit the 1 inch belt to any set of camshaft pulleys. Some pulleys are plastic, some are aluminium some have belt stops at the front some have them at the back and some have them both front and back. Look on Guy Croft's website or give him a call. Or fit a heavy duty 3/4 inch belt ;-) http://www.needforspeed.co.uk/pages/sbv_pl.asp?Vehicle=FT13101&PartType=CAM08

Excellent.
Thanks for saving me a shedload of work, or potential work wnyway.
I'm ordering two, one for each car and while I'm fitting them, I'll check out what pulleys I have.
Thanks very much