[BallyChally]

Hey all,
Chasing some recommendations for an aftermarket Carby for a 1993 vitara with the g16a engine
I’ve seen the Toyota 3k carby is popular with the sierras

I just picked up this vitara and it’s runs rough on idle,
I love the simplicity of the 3k carby and they seems pretty cheap to buy

I live Perth WA and there’s not so many parts available

Cheers in advance for the advice!

[sideways]

I have a 3/4k carby on the G16a in my sierra.

It's on a sierra manifold so I have no idea what you'd need to do to make it fit a vitara. For mine I had to make a throttle cable bracket, cut/weld/shorten the bellcrank to give full throttle, make some studs to go in the intake manifold, mod the carby hat so the choke doesn't hit it and probably some more stuff that I'm forgetting.

I had to go down quite a lot in the jetting, especially on the primary. I tuned it with a wideband oxygen sensor.

I blocked off the power valve, it's poorly machined in the ebay carbies and doesn't seal properly which makes the AFR jump around all over the place.

Running rough at idle could likely be a vacuum leak, a poorly adjusted idle mixture screw or blocked idle circuit.

[AckerDackerly]

If I am understanding what you have asked, you have an 8-valve G16 engine on your 1993 Vitara. If that is true, you CAN swap in a sierra G13 8-valve head and carby intake on the G16a engine and then install a Toyota (or other similar carby conversion for a G13).

You CANNOT do this on the 16-valve G16 head as the intake ports are not positioned in the same way as on the 8-valve head.

I ran several aftermarket carbys (Weber DGAx 32-36 and Mikumi 44mm side-draft with an adapter) on a G16 engine with a G13 head (yes, they do fit!) on my 1988 Samurai (North American Sierra) with great success. Unfortunately none of them were the Toyota carby, so I do not have direct experience with that. I do not recommend the Weber swap - they are very difficult to keep running properly.

One of the "benefits" of this conversion is that it eliminates the ECU and wiring that supports the stock fuel intake system. The main disadvantage of the modification is that it may not pass MOT inspection! Here in the "up-over", California and a few other states have very strict rules on this topic. Check the state/federal engine modification rules before proceeding.

I hope that this helps!