4k Hesitation/Missing

[1goodidea]

Hey, i've just swaped in a 4k in place of my 2k motor in my starlet

Heres the setup
4k motor
4speed gearbox
2k carb


Problem
Car isn't idling smoothly - the motor is abit shaky
Then when you do drive it the motor hesitates at low revs

what would course this?

I have pulled plugs out and cleaned them, no difference

THEN

swaped plugs and leads for the plugs and leads that i had on my 2k motor which ran very smoothly still no change.


any thoughts?

[fuel]

Could be the 2K carb (which is designed for a 1000cc motor), is having problems delivering air/fuel to the 1300cc 4K. Are you sure it's ignition related? Could be distributor cap/rotor/points (if it has them) etc.

[1goodidea]

I heard the 2k and 4k carbs are the same?

I've done the swap before and it ran absolutely fine with the 2k carb?

[wde_bdy]

There are different size jets in the carb.

Callum

[EVL20V]

had similar problem putting diff. carb in 2 a corolla. a possible fix could be installing a monsta tach..

[1goodidea]

anyone else with some idea?