Ok, I think I know how I can use the 3.0 and ditch all the emissions and electronics junk. The image should help to explain, but i'll do my best. I'm going to pull out all the sensors, about half are threaded into parts I've already ditched, like the air sensors, or otherwise easily removed, like the MAF, and then for about a quarter of the rest, like the 02 sensors, I'll pull them out and weld little plates to cover the holes. For the last quarter, like the CPS, i'll just leave them in and snip the wires. Now, Since I want the engine to be carbureted, I'll find some way to gut the throttle body, like cut out the throttle plate, weld over any holes, and then pull out the fuel rails and injectors and either weld them shut, or use a lot of JB weld to plug them up. That way I won't risk losing any compression, messing up the air/fuel mixture, or ect. Now, remember how I hollowed out the throttle body? That will serve as a nice little spacer. I think it's 4" wide, so I'll get a 4" pipe with a 90degree turn upwards, and then custom-fabricate a plate that I can bolt a carb to without restricting airflow, and weld that onto the pipe. Bolt on the pipe, bolt on the carb, cross my fingers and hope to god it starts!

 

Why would you do this?

 

x2

 

For my rat rod project, I'm trying to get rid of the electrical and emission systems to keep the engine bay simple

 

Why not just a carbed Small Block V8 or 2.3, or lastly a 2.8. Carbed 3.0 = good luck!

 

Good luck and keep us posted - I'm sure everyone would be pretty interested in how it goes.

FWIW, I think you'll find it easier to put in something that fits that was designed with a carb originally.

Still, it'll be interesting to follow your project . . .

 

And just what are you going to use for a fuel pump ?
A carb won't work with a fuel system running at 45+ pounds of pressure.It needs to be knocked down to around 7-10.The existing intank pump is too much.

 

No good will come of this.

 

put a 460 in it and call it good it will be sick then

 

No reply here dude, sorry, but that is 1 sweet avatar you got !

 

Putting in a v8 is plan B. If you think it should be plan A, tell me in the project log, this thread is here because I want opinions on my idea... I really think it could work, all I'd need is a new gas tank / fuel pump, carb and a bit of piping. If that falls through I'm out less than $200 and I'll start looking for a v8.

 

You can get an aftermarket fuel pressure regulator to bring the psi down so yo don't have to buy a new pump.

 

i'd be concerned that you would lose sensors that would effect the operation. Example- does CPS get any input from MAF sensor to run properly. I remember Rich saying the timing changed when the air temp was over 80 degrees. What happens when no input is there at all.

You could end up with a wiring nitemare.

Let me give a real world example. I converted a 4.3 s-10 from FI to a carb. It was pretty easy cause the 4.3 was made in both formats over the years. There's a low oil pressure shut off that would prevent the truck from starting. Disable this one sensor (purposely or by accident) and the truck didn;t start. It got to be such a mess that i ripped all the wiring out and started from scratch, including aftermarket gauges. That left me with a tranny swap to the older 700r4 since the 460le needed computer inputs (which I ripped out with the other wiring).

 

From what I understand, and I could very well be wrong, the 94 tranny doesn't need any inputs. And it doesn't matter too much because I refuse to put an auto in a rat rod. A blown tranny is the reason for the project in the first place, so I'm just goingto swap it out for a 5 speed.

My goal is to see if I can get it running with no computer bits at all, or very very few.

 

that would be the idea. In my case, the truck still had a distributor and was able to swap in an older distributor that had a manual adjustment to it. Timing is the one area I am concerned you'll have problems with. Rwenzig would have the answers. He has the best understand of wiring that I have seen on the forums. He hasn't been on line for a while.


Moving past the wiring, I would have concerns of the gas puddling from such a sharp bend as you have pictured.

 

couldnt you find an intake manifold that would hold the carb instead of piping it? I dont think youll even get good response from the engine.

 

If memory is right, the 2.9 was carbed, all 3.0's were injected. No manifold exists.

the only possiblilty I can come up with is taking either the base from a whipple or an older 3.0 aluminum intake, then graft the top of an edelbrock aluminum intake to the top of it.

 

Another idea is to j bend the intake tube to the top of the motor. Tied it into a round carb style filter. You could get the look of a carb motor, but keep the guts fuel injected.

The nice thing is there are no rules with rat rods. Anything goes.

 

Thanks for all the input!

I went out and looked over the distributor, there is one plug ith several wires coming out the back of it near the bottom, so I'm thinking it's either just a sensor or it me be an electronically adjusting distributor, in which case I should be able to swap it out with an older distributor, the Vulcan has ben around since 86, I'm sure I can find a distributor that will work with no computer.

If I can stop the gas from pooling in the bend, do you think it would work as far as delivering fuel?

 

i don't like the bend. In carbed applications everything seems to be running down hill with very little horizontical movement. The spray mist from a carb is not as fine as fuel injected. Its bigger droplets, thus heavier, thus the opportunity to puddle on the bottom.

The velocity is also lower in the large tube compared to a carb application where one small runner full of air and gas is being sucked in by one cylinder. That same suction from one cylinder has to keep the gas suspended in the larger j bended tube.

Another concern is whether all 6 cylinders get fuel. I can visualize the front 2 cylinders getting too much fuel and the amount decreases as it goes further back.

All of this is specualtion.

 

I'm impressed by your ingenuity! However, I suggest that you learn the basic concepts of how an EFI system works, and you will then realize that going
to a carb is a huge mistake!

 

Does your engine? have a distributor or a coil pack.

 

if an aftermarket carb manifold was available, I'd have to disagree. Since it's not, it's gonna be a chore and a half to do it.

I don't think there's a worry about losing the warranty on it. lol.

 

I don't think he's doing it because he thinks carb is better, I think he's doing it for more of that rat rod theme.

 

Even if a carb manifold was available, there is no advantage of a carb over EFI. Way before EFI was available, mechanical fuel injection offered a performance advantage over carbs, as was seen by Mercedes (article below) and Corvette.

"The engine, canted at a fifty-degree angle to the left to allow for a lower hoodline, was the same 3.0 litre straight-6 as the regular four-door 300 but with a Bosch mechanical direct fuel injection system that almost doubled its original power of 86 kW (115 hp) in the original carbureted trim. This new injection system was a first in any gasoline-powered car - apart from the rather small Gutbrod where the Mercedes engineers, who had developed the principle for the DB 601 fighter aircraft engine, had to work after the war. It allowed a top speed of up to 260 km/h (161 mph) depending on gear ratio (several options were available) and drag (bumpers were optional, and race tyres fitted for tests), making the 300SL the fastest production car of its time"