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That's the question.

I had an interesting carb fire today. I had a backfire through my number one carburetor. That has never happened to me before, but I was running the car hard, and shut it down pretty abruptly. Not a huge problem in itself. But, I have the foam style filters. It caught the foam filter on fire, and then sucked the filter into the engine. Caught the carb on fire, and melted the auxiliary venturi's in both corresponding throttle bodies.

This is what I was left with.


This is the aux-venturi. They both are melted.


I pulled them out, and removed all the renaming chunks. Started car back up, and it runs like a champ.
Is there a negative effect to running without the auxiliary venturis for a few hundred miles? I have to drive out to work tomorrow, and I don't think I will be able to find new ones before I have to go. This is my only vehicle.

snwbrderphat540

venturis are pretty important... but if they are aux ones as in secondary ones, you will probably be ok for a short bit. doubt you can damage more by running it.... but get it fixed

KasbeKZ

wow. i just have to say that that must be about the beastest little backfire there. that's like race car ****.

anyway, aux venturi? is that not basically a smaller venturi into which the fuel is delivered? so if your fuel port is still open (obviously it is if it runs well), then your only problem is that the fuel won't be atomized as much cause the air isn't flowing so close to the jet. (my experience is with the down draft, so forgive me if i'm getting the jet designs mixed up. i expect that they are the same). so if it's running now, i don't think it will get worse.

i do think that you need to find out what caused such a bad back fire. that was WAY too much fuel sitting in that carb. were you pumping the throttle? i don't like how much the accelerator pumps spray. you can get different cams for them

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My problem has been figured out tonight. The regulator is not working, and I am running too much pressure. I think that is what cause the extra fuel, and fire. I will get that fixed tomorrow. That's the easy one.

I will run around town tomorrow, and try and locate some parts locally. While driving around, that will tell me how things are running. I am sticking some new plugs in there tomorrow morning, and I will see what they look like after some short runs.

I was surprised that the venturis melted at so fast, even for aluminum.

I now have more parts to stick on my shelf. The shelf I named. "Offerings to the God's of Speed". Got it from Burt Munroe. haha

KasbeKZ

good stuff. one of the all time best movies.

anyway, good luck with that. i'm surprised that too much pressure would do that. the needle seal makes pretty good contact in the inlet from the line. it must be a lot of pressure. how much pressure is your pump capable of? i think mine did like 5 tops. and it was a good one.

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It was peaking at 12psi today. I have a gauge on the line in between the #2 and #3 carbs. I didn't notice it until later tonight messing with it trying to figure it out. I have an after market Holley electric pump. It's nice and strong. I don't want to put a bunch of time and money into these carbs. They have been fun, but I want an L28ET with megasquirt, and fuel injection to play with and tune now. I have gone the carb route is every form I can think of now. haha
2bbl, 4bbl, three 2bbls, quadrajet, side draft, quad sidedraft in 4 different forms on motorcycles etc. It's fun. But, I have not had the joy of playing with a stand alone fuel management system yet. There is just too much fun for one man to have there.

KasbeKZ

i agree with the plan for a megasquirted turbo. that would be beast.

that's a lot of pressure! i guess it's really about normal though. it's just a lot more than i am used to working with on carb'd engines

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I don't know how long it's been running like this. But, I did notice that when I took a trip, I used more gas than usual. I figure it was my heavy foot. But, now it makes more sense. I did take a G35 uphill today. On the way home, I took a 4th gen Mustang GT. I think the mustang would have had me if he knew the road better, or could drive better. It sounded healthy for the 4.6l modular engine.

snwbrderphat540

damn 12 psi!!! thats alot for a carb setup, i know those triples like lots of fuel and all but thats pretty damn high. yeah time for turbo power

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Haha. I had it regulated at 6psi. That's where it seemed happy. The regulator got stuck I think. It's a cheap specter.