TBI distributor just for fuel timing?

I know on the magnums the dist is just for fuel timing, is this so on the TBI engines too?

Post deleted by 340SHORTY

Bump for anyone else? As I thought the dist on the magnums also doubled as a cam sensor?

I can't think of another way (on tbi eng) the computer can find info to pulse the injectors, so it probably does both.

I can't find any info on it.

So I suppose the dist on TBI works like a carbed engine, and is adjusted by the computer.

Anyone know how to set base time on it then?

As far as the fuel, I would assume if the dist has nothing to do with it, then there should be a pressure regulator that would up the pulse for more load?

There is a spec for base timing, on decal under hood. It is set with eng at running temperature and the 2 wire coolant sensor on intake man. disconnected. I believe the pressure reg is built in to throttle body.

this isn't in the original truck, its in a car now, so the stickers long gone.

I guess I need to spend a few hours in the garage looking for my 90 shop manual!

If you are using the sbec and the rest of the truck controls on that thing, I would set it at 10 btdc for baseline.

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I can't find any info on it.

So I suppose the dist on TBI works like a carbed engine, and is adjusted by the computer.

Anyone know how to set base time on it then?

As far as the fuel, I would assume if the dist has nothing to do with it, then there should be a pressure regulator that would up the pulse for more load?

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The magnums use a crank sensor for sequential fuel injector timing and use the distributor pickup for ignition timing. On the inside a EFI distributor works nothing like a carb distributor, but on the outside you twist it to adjust base timing the same way as a carb distributor. I would also suggest 10* BTDC as a good baseline to start from.

On a TBI setup, the distributor typically has a pickup that tells the computer each time the rotor is at a certain point in its revolution. A TBI dist usually sends one pulse to the computer per revolution and the computer uses this information to help caculate spark advance(in addition to the base advance). Also a TBI computer will use this signal to time the TBI injector pulse. So the TBI injector will pulse at the same time in the engine's revolution, every time. This signal from the distributor is one of the inputs the computer uses to calculate injector pulsewidth.

Fuel pressure does NOT increase on the fly to account for engine load.