HIF44 fuel density/temperature sensitive thingy.
Turbo Mini Forums

I have read somewhere that there is a little device(Bi-metallic strip?)in the float chamber which is supposed to regulate fuel in some way according to the fuel temperature or density.Am I talking cock -probably.Does it do anything we are bothered about?.Can it be removed without giving problems?.

hi tadge ,
i dont know if this will come out clearly enough ,but here is a log from avon drag racing ,if you click on the picture ,then click on full size it should be vaguely legible.




the black is rpm ,the blue is boost ,and the pink is the air fuel ratio ,,

if you have a look ,you can see some points where the boost and rpm are similar ,but the mixture is about .5 afr different ...

this was with the engine warmer on the 2nd run ,and i feel the bimetalic strip had reacted by leaning it off about .5 afr from when it was colder .

i keep it in for economy reasons ,and credit it with giving me the 42mpg i can get at normal speeds .
regards
robert .

Edited by robert on 20th Oct, 2008.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Hi Robert -thanks for that. I had wondered if it was interfering with my amateur attempts at tuning my turbo motor but it seems that I had better leave it alone -one less variable to worry about. I thought that I had read on a thread somewhere in this forum that they can give trouble and were best left out.

actually tadge , its introducing a variable to leave it in,
i think a fair few people have replaced them with a piece of stainless , and if your going for competition work ,where it may be running on the edge , i think i would take it out too.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Thanks again for the tip - I dont intend more than the odd track day and will be mostly showing off on the road from time to time so I may well leave it in.I understand your comment about another variable,but if I leave it in it is one I have not yet mucked about with !

Years ago Turbo Dave wrote a fair bit about this, well worth a read:

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=311

I won't try to re-cap as I'll only get it wrong.