Throttle body

[carlosiw]

Hi all. First of all, nice site! Really like all the DIY articles.

Just wondering at what revs the second stage (buttlerfly) on the throttle body of a 16v should open. Mine doen't open no matter how hard you rev it; it seems there should be some kind of adjustment screw (mine's missing if that's the case) that gets pushed when the first butterfly opens to a certain point, which in turn opens the second throttle. (I can prob. fabricate something for this) I'd like to sort this out as I must be down on power because of this!

Any ideas really appreciated

[Chaps]

Isnt the 2nd butterfly linked to the throttle position not the revs?
Yeah it will open at a certain rev range, but i think that just because you have pushed your foot down that far to get to that RPM. if that makes sence.

Thats how my old twin butterfly carb used to work. i'd imagine it would be the same principle? Is there a linkage missing? or a screw as you mention?

[Nate]

most 2 choke carbs (and i assume inj cars will be similar) open the 2nd butterfly when your foot is almost all the way down. it is there more for hard accelleration than for cruising at a constant (even quick) speed

[roccodave]

if something came off the linkage the air rushing up to the butterfly would push it open and you would get full throttle and probably s**t yourself
it happened to my webber when i was going round castle coome (it was a spincter blinking moment)
try and find another one to see if it does the same as yours if it dosen't just replace it

[carlosiw]

Thanks for your thoughts everyone; have checked and yes it does open up with pedal almost to the floor so maybe that's all there is to it. Does look very muck like some kind of adjustment screw is missing though! (There's a threaded hole for one) No big deal though, it still goes well for a 22 year old car!

Carl

[Chaps]

stick a screw in it then and see if it makes any difference .
I'd imagine it will if it looks like ther should be something there.