My Street Demon install experience

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On the choke are you turning the key on, pushing the gas pedal to the floor once, then cranking it?
 
On the choke are you turning the key on, pushing the gas pedal to the floor once, then cranking it?

Yes, that’s been my procedure thus far. I’ve been told to give it a couple pumps before I turn the key on. Then turn the key on and give it one pump to set the choke. Your thoughts?
 
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Ok, so i adjusted the fast idle screw and that seems to do the trick. Holley says fast idle should be 1500-1600 rpm. I’m at 1400 right now and it started easily. I’ll keep trying for the next few days before I declare it finished.
 
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So I was doing some tuning and the car began to run like a dog and would barely idle. I pulled all the plugs and they looked great so I changed the fuel filter and drained it into a cup and..... uh oh.... this aint good. So I bought some clear filters so I can monitor the situation. They were less than $4 a piece. I'm guessing the tank needs to be changed but I'm wondering if I can just filter the crap out of it after a few tanks of gas????

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Drop the tank, you have a lot of crap in the tank and lines.
Take the tank to a radiator shop and have it boiled out.
Disconnect the fuel line and get a small aquarium pump and circulate white vinager thru the fuel lines.
 
Drop the tank, you have a lot of crap in the tank and lines.
Take the tank to a radiator shop and have it boiled out.
Disconnect the fuel line and get a small aquarium pump and circulate white vinager thru the fuel lines.

So this is better than ordering a new tank with a new sending unit? My gas guage doesn't work either.
 
So this is better than ordering a new tank with a new sending unit? My gas guage doesn't work either.
Yes
Could be old gas
What's the story about the old gas? How long has it been there? How full the tank? Through what sort of weather cycles?
Depending on the answer first thing might be to just refill with clean fuel (after draining the old) and installing a new 'sock' filter.

You may have to ask around for a bit to find place that will clean a fuel tank. Restorers and owners of old bikes, MG, Saabs and things like that, or antique cars and trucks without aftermarket tanks - those are the types of folks that are most likely to know a place in your area. Antique car shows and swaps meets would be a place to find those folks.

Fuel gage repair. Yes big time. The aftermarket ones have issues.
There's at least four or five places that will rewind the resistance wire if that's what is broken.
When you remove the sending unit, it may be obvious what needs fixing.
On the outside the wire should be attached to the sender. Don't laugh - the one on my barracuda falls off periodiclly. LOL
There also should be a ground strap from the tank nipple to the fuel line.
To remove you can make a tool for the lock ring or use a brass or aluminum roundstock or punch and gently tap ccw.

Fuel line. if its really bad, then a repop is worth it.
 
PS. if you post the mechanical timing vs rpm we should be able to tell which advance mechanism is in there and what is probably going on there.
 
Should be able to set it with an initial of 10 -14* around 600 rpm and be around 30 - 32 around 2800 rpm and 34ish at high rpm. That should work on 340 or any hot rodded LA.
 
The gas was about a year old with stabilizer in it. The car was always stored in a garage and it only had a few gallons in it. The fuel filter was installed about a year ago as well when I replaced the fuel pump. I probably blew the sock off when I was trying to get the Thermoquad to prime. Car runs really good right now with 10 degrees initial.
 
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So this is better than ordering a new tank with a new sending unit? My gas guage doesn't work either.

Better, not sure it depends on the condition of your tank and pick-up.

I know two years ago I bought a new tank, pick-up and straps from Tanks inc, at Carlisle for my 70 challenger and it was $220 for everything.

What ever you do save the original locking ring off your pick-up, the repos don't seal right.
 
Ok, so it clogged another filter in about 20 miles of driving so looks like I’m gonna have to drain/remove/clean or possibly replace the tank. Now I gotta figure out how to drain, filter, and store about 8 to 10 gallons of gas til this gets done.
 
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Buy a cheap 12 fuel pump from Napa $40 and about 15’ of fuel line, suck the tank dry, the pump comes with a small filter, I would also put a clear one to catch that nasty stuff in the tank.
If you filtered the fuel real good, burn it up in your push mower.
 
Initial, this is a mild 340 with J heads and small port Weiand 8007 Action Plus spreadbore. I haven't driven the car much in the last 10 years so I'm gonna run this gas out and do some tuning before I speculate too much. I will report back how it's running. I'd be surprised if it needed larger jets.
I highly doubt it too. I would be willing to bet it actually needs 2-3 steps down. Carbs are always severely over jetted for liability concerns. You won’t know exactly where it is until you install air fuel gauge. I used to rely on reading plugs. But, Ive found the air : fuel ratio can be very rich even when the plugs don’t necessarily show that. I thought my car was running very good by upsizing the jets from where it was jetted when it was shipped. I found after a gauge it actually needed 3 steps down on jets. Makes a lot more power now.
 
Yes, that’s been my procedure thus far. I’ve been told to give it a couple pumps before I turn the key on. Then turn the key on and give it one pump to set the choke. Your thoughts?
You don’t necessarily need a choke. I live in a colder region. My car never had a manual or electric choke. All you have to do is pump the pedal 5 or 6 times if car hasn’t run in a couple days. It will fire right up. You just need to feather the throttle for 10-20 seconds until the engine builds a small amount of heat. When you restart the car after it being warm. It’s not needed there either. Just turn the key it will fire up with no throttle input needed. I actually removed my choke valve. So it doesn’t accidentally close while running the car. I put 5k miles on my engine never having a choke. Some engines won’t start without one. These carbs self prime themselves when you pump the throttle. It squirts gas, not necessarily needing a choke. .
 
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You don’t necessarily need a choke. I live in a colder region. My car never had a manual or electric choke. All you have to do is pump the pedal 6 or 7 times if car hasn’t run in a couple days. It will fire right up. You just need to feather the throttle for 10-20 seconds until the engine builds a small amount of heat. When you restart the car after it being warm. It’s not needed there either. Just turn the key it will fire up with no throttle input needed. I actually removed my choke valve. So it doesn’t accidentally close while running the car. I put 5k mines on my engine never using a choke.
Do you need a choke, it depends....
I had the 625 street demon on my truck at 0 deg F start on the first crank, and jump up on high-speed idle.
Push the petal once, roll the engine and fire up to an idle speed, that I could walk back in the house until it warmed up. Way nicer jumping in a warm truck.
Did this several times, when my wife would steal my Jeep to get to work in deep snow.

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Do you need a choke, it depends....
I had the 625 street demon on my truck at 0 deg F start on the first crank, and jump up on high-speed idle.
Push the petal once, roll the engine and fire up to an idle speed, that I could walk back in the house until it warmed up. Way nicer jumping in a warm truck.
Did this several times, when my wife would steal my Jeep to get to work in deep snow.

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That’s what I’m talking about. Lol ! Sure, an electric choke is remotely necessary if you want to walk away from the car immediately after it fires. Otherwise, it’s not. With a manual choke, you don’t have the convenience of immediately walking away from the vehicle when it initially fires, either.
 
With a manual cable choke you have to play with them, have one on my old 48 willys jeep.
It also will start first crank after sitting all winter in storage.
Pump the gas once, pull the choke and it idles, then feather the choke until warm.
 
sounds like the O-rings, or a needle seat, or terrible float setting, but I'm betting the o-rings
sounds like the rebuilder F'd up. I like that Street Demon design myself. I feel the TQ was the leading edge in carburetor design when it was introduced.
 
With a manual cable choke you have to play with them, have one on my old 48 willys jeep.
It also will start first crank after sitting all winter in storage.
Pump the gas once, pull the choke and it idles, then feather the choke until warm.
I agree with you. My carb didn’t come with electric and I didn’t necessarily want to mount a manual choke to my fully restored, full original look dash. I initially tried, but regardless of how it was routed. The cable would always bind. So, I threw the brand new cable in the trash. lol ! The car starts as easy as any other, without one.
 
As long as any engine has good compression its going to light right off, if it is old and tired then good luck.
 
Took about an hour to remove the tank. Mine is an early 71 tank with 4 vent lines. Bottom of the tank looked pretty good but the walls have a thick coat of rust. I have elected to order a new Spectra Premium CR11D tank.

WHAT ELSE SHOULD I ORDER???? sending unit? filler neck to tank seal?

The filler neck looked pretty good. Just needs some light cleaned up.

Tank pad looks ok. I think I can peel it off and reuse.

Gas guage doesnt work and the original sending unit looks pretty nasty. Are all the aftermarker sending units junk????

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I would get a new tank, sending unit and gasket.
The pad is re-usable, if not patch it with some roofing tar paper.
 
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