1991 Hotwire 400 SE FREE

[beduch]

Wanted free advice on what should the CO2 be set at on a 1991 400 SE Hotwire, and does this affect the mixture only at tickover or all through the rev range Thakks for any advice

[nickleby4]

Hmm. 2nd attempt at a reply. The one I look after likes the CO to be set surprisingly low 1.5 - 2.5%. (It also does not like high fuel pressure - again surprisingly, so if you've got strange readings / performance that could be it (you can ususally tweak the pressure up and gain a little performance with this style efi, so if somebodies been playing...))

It also insists on a relatively high idle - approx 1250rpm, and has a disapointingly long plug warm up time (after fvery short engine off - eg. 2mins), during which it will not idle unassisted. Any of that familiar?

As to the CO adjust - theory and practice: It's an air bypass line to divert some of the airflow away from the flap, such that the flap finds the correct position for the ecu to supply the correct fuel qty (think of it as an electric tap - the further the flap moves the more fuel the ecu gives) In theory then it will have an effect accross the range. In practice it has very little effect once the throttle is open, and none at all at full chat.

Hope that's helpfull.

[shpub]

CO adjust for a flapper is not the same as for hot wire. Mark adams adjusted the CO on my Griff (Hot wire) but had to do this by tweaking the ECU.

Pretty sure that the Hot wire system is a sealed (can't mod) unit and any adjustment is at the ECU end.

Steve
www.tvrbooks.co.uk