What jet sizes do use run in ya 3k? or 4k?

In our speedway car we are running 195 or somthing like that and still running lean?

In the secondary btw

Cheers yall

Allright its actually 230, dad drilled them this morning. There must be sumthing wrong? i go for a thrash between 4-8 in second and come back and are white as white can be? thanks

If you are running Avgas, then that's perfect!!

If you are running Avgas, then that's perfect!!

 

Hahah, nah mate good ol bp 98

gee people use are VERY helpful

Were running 141 in pri and 195 in sec, no problems.

The pri jet is the one accessed via the bolt on the carby, the sec one you need to lift the air horn off.

fuel level in float chamber OK.

 

Check the power valve cct is not blocked, to do this.

remove air horn.

Unscrew power valve.

Check lower part of power valve and its jet is clean, unscew the jet as well.

Blast some air down the power vavle hole of the main chamber, confirm Air flows out into venturi via boster. ( this is the part that provides extra fuel at low vacume )

Next blast some air down hole that is located just near the power vavle and between the to venturis, air should flow in to ventuir down near butterfly , this part senses vacume and controls power vavle.

in air horn check power vavle plunger for smooth opration and remove plunger taking note of how the retaining washer is located.

Blow this out with air.

Re assamble and take note that gaskit between main body and air horn not damaged around power valve vac path.

from memory the power vavle dischages into sec ventui but pick up its vacume for the pri venturi but I'm not 100% sure.

 

CHeers

Andy