Cheap Co2 Air Fuel ratio meter

Decided I need an air/fuel ratio meter, rather than buying one for £200 or making my own, which cost near this figure anyway I guess - this little microprocessor thing looks good. Those cheap 52mm dial things you get on ebay are crap and aren't actually the right thing!

The system consists of 3 things.

A weld on adaptor which you add in the exhaust after the 2-1 bit on a sports manifold....You can remove and refit the Lambda sensor. £5.50

This neat little box with two readouts- numbers(440ms - 1/2second) and a faster reacting bar read out (220ms), this is £39.99 incluing post from http://www.ct-tuning.co.uk/product_info.php?products_id=51 he seem to sell some good stuff, techie kinda guy.

The 3rd item is of course the Lambda sensor, £15-17 on ebay. You can use 3 wire one or 4 wire, 4 wire has a heating element so doesn't need the exhaust/gas to heat to 300c before giving a good reading. I'll probably get a 4 wire one as they cost no more really.

Good tuning tool....I hope to be able to tune my pump jets and low end running even further with it...I can then not waste money on a rolling road with someone else doing any jetting...I can get the jetting bang on 100% on the road and go rent this rolling road I know off and just tune the ignition myself with back to back and pegged tests as fuelling tuning on the rollers isn't a reaslistic display of road driving in many cases.