X2 carb jet sizes

[smithy]

gday everyone, i just got my hands on an X2 twin stromberg setup and was wondering if anyone could advise me of the best jet size to use or modifications i can do to get a little more grunt without watching the fuel gauge drop( motor is 186+ 60thou, stage 3 head and mild cam) also are there any tricks to tuning twins that i should know.
thanks a bunch

[brads59]

Hi Smithy,
they tell me if you get your linkages set up right you should have no probs.
Apparently the hexagonal linkages are the way to go.
As for getting performance out of a stromberg,well i have run a 2mm drill bit through the the jet on a couple of mine in the past,but not recomended if wanting to retain fuel economy.  CHEERS   .......BRAD

[Jockster]

G'day Smithy
I run a set of X2 Carbs on a fairly warm 192 in my FC. The only change I have made to them is to run 202 HQ Stromberg Power valves (helps with mid range power) and I fitted sports air cleaners. The car has quite good acceleration and top speed and at normal (legal) open road cruising does about 9litres/100Km (about 30 mpg) which is pretty good, I am running a 3.08:1 diff ration on 14" wheels too which helps economy
Cheers
Jockster

[smithy]

thanks guys thats helped heaps.

jockster, 30 mpg sounds good. i'd be happy with that.    i will be running a 2.79 ratio diff (commodore) behind a 5 speed and 15in rims and tyres (50 series) which will bring it back to around 14. im hoping to set the car up for highway travel, hence the tall ratio.
thanks again
dean

[nicko]

those ratios are good for hi way but been tall it will suck the juice around town due to working harder to get off the mark

[weedy-burton]

Hey Smithy,

You can get adjustable jets for these carbs,the same as the HQ racers use.I have a set in my twins,I got mine from my local auto one store but you should be able to get them from any good auto parts store eg repco etc.
I think they were about $8 each when I bought them.

Weedy....