converting to carb

[cyclonebuzz]

hey i was wondering if anybody knows how to or has converted there sidekick to carbs. i have a 1991 geo tracker 1.6l 8v tbi 2dr. 4x4 auto. i know alot of the samurai guys us the 1.6l 8v in theirs. i know the computer is intergrated with the fuel injection and inigtion. so that causes problems to over come but besides that on the tbi it looks like u could make a carb work the way its set up. well i was just wondering if anyone had some insite on the issue. oh if you are wondering why i want to its because i did some motor work to the lil thing. so i am not for sure if the premitive fi will adjust for it.

[jtgh]

only issues is keeping spark going.

i guess I should know, I have a ECU then runs with out motor. huh?
it is on a table and I have all inputs simulated.

it runs, as soon as i bump start it, with my CAS generator.

If you can ,I would keep the MAP connected , that way , it wont get mad and drop to failsafe mode. The map is easy ,must connect the vacuum line to the plenum. as it is now.
course the OXy sensor, and IAT are useless but id keep IAT. or a dummy 500 ohm resistor.

the only thing to avoid is the fails safe mode and the attendant punishiment of retarded timing. So all sensors (sans O2) should be present or replaced with resistors.
the ECT needs to be present because i think timing is different cold compared to hot.
the EGR is the tricky part.
your 91 my not care about EGR fail. but if you get code 51, you will get retarded timing.

if you are serious , i could make a simple chart showing what to do with each.
(I assume you want to keep ECU for spark) other wise you need a dizzy that spins in the correct direction, (CW in your case) old sammi dizzy?


i might add , my bench tester runs with out any DTC codes.
how ever id did get on dtc for bad oxy sensor ,by deaccerating too fast for too long
and discovered there is a monitor for OXY that expects lean mix, when it does a long cut fuel during long deaccelerations. ( it clears quickly by itself once I cruise)

the real issues is the timing curves, you might not like them.
they would be useless with boost.
or with high compression mods of any kind.

cheers.

[cyclonebuzz]

thank you for all the info and i am realy serius about trying to convert it over to carbs. i just wander how the samurai dose its spark timing. i mean is there a computer on them or is the whole thing in the distributor. like u said the issue is keeping spark going. maby there is a way to get rid of the comp?

[Rhinoman]

I have a 1.6 8V with carb fitted in an SJ413 pickup. I used the stock 1.3 carb and manifold with the ports opened out. The ignition uses the stock 1.3 setup - dizzy and coil. You need the 90deg housing from the 1.3 as well because the 1.6 dizzy has a longer shaft. You will also need a low pressure fuel pump, this wasn't a problem for me because my 1.6 was a carb model and has the mechanical fuel pump. The dizzy is fairly easy to modify to change the timing curve.
The 1.3 carb is really too small for the 1.6, a 1.6 carb or Weber would be a better choice, if you really must lose the EFI.

[CodyJ]

I am sure any mods you have done can be handled by the fuel injection throttle body. It is basically like a carb without the problems of a carb.

[cyclonebuzz]

ok thank you so much for the info. if the f.i. will adj. enough i will just use it. i was just concerned that the f.i. didnt have a broad rang of adj. . i am going to do some head work to it and put a cam in it. so i didnt want to get it togetter and it wont run b/c of the f.i. wont adj. . but hey if it will then less work for me lol. if not i got to find a 1.3 manifold and dizzy.

[Rhinoman]

You will struggle to get the stock EFI set up with a different camshaft. The ECU can only apply single a mixture correction across the whole load range. The internal fuelling map is based on the Volumetric Efficiency of the engine. A high performance cam will tilt the torque curve (and hence VE) such that the fuelling will be lean at higher RPM and rich at lower RPM. You may be able to compensate to some extent with a rising rate fuel pressure regulator.

[jtgh]

that is way we have megasquirt. ( DIY, tuning)

lol.
but it is a pistol. needs missing drivers. had to add 2 drivers, one for IAC and one for dash pot, just to get it to idle correctly.
its like DIY in spades.