Chinese 40 idf carbs!!

[fastoldvw]

Hi, I just went and bought a set of Chinese 40mm idf "no brand" carbs for my torque built oxyboxer 2276cc engine.
I am now in the process of changing the jets/venturi's as the ones delivered were not the size i need and the venturi's were very rough looking. I'm machining the venturis to 32mm and upping the jet sizes as per Bob Tomlinson ;-)

I know that i need to check float height and port the inlet a little

Question is: what else should i be checking on these carbs?

Anyone running these with succes?
 
Thanks Rune

[Phil West]

Check any remaining jets (pump, idle, etc.) with a jet gauge to be sure they measure at what they say are.  Check for any flashing and blocked jets.  Check float hinge pin to ensure it will remain secure.

As per:

http://cal-look.no/lounge/index.php/topic,12904.0.html

Cheers
Phil

[alex d]

I would take the jetting charts in the bob tomlinson book with a grain of salt

[fastoldvw]

Yeah, i've been informed that bob's charts might not be the best place to look, so maybe someone here can get me a rough estimate on jetting these 40's?

Engine is 82x94 2276, 5.6" rods, Engle 120 cam stock rockers, 40/35,5 heads, 9:1 comp.

It will sit in a baywindow Crewcab, and will not see more than 6500ish rpm.

The venturi's are now 32mm

[Jim Ratto]

Yeah, i've been informed that bob's charts might not be the best place to look, so maybe someone here can get me a rough estimate on jetting these 40's?

Engine is 82x94 2276, 5.6" rods, Engle 120 cam stock rockers, 40/35,5 heads, 9:1 comp.

It will sit in a baywindow Crewcab, and will not see more than 6500ish rpm.

The venturi's are now 32mm

32mm chokes in that size motor will allow usable power to 5300 rpm.

I would use a 55 idle
F2 emulsion tube
135 main
185 air corrector
closed accelerator bypass

Sincerely,

Jim

[RMS Boxer Service]

Deburring deburring cleaning cleaning and genuine Weber jets E-tubes then you have a chance

/Rolf