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  #21 (permalink)  
Old 07-23-2007, 04:31 PM
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thats too bad Rob. If one of my venders continually fails to provide support after the sale, I start looking for a new one. In my business, customer support is #1.

I hope you get it all worked out.
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  #22 (permalink)  
Old 07-23-2007, 04:34 PM
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Do you have a vacuum advance? Is it plugged into the right port on the carb? I have seen that mistake a few times with similiar results as you are experiencing
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  #23 (permalink)  
Old 07-23-2007, 05:51 PM
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Quote:
Originally Posted by xlr8or
When in nuetral and on the brakes hard will it keep running if you hit the gas pedal? If not it may be an electrical short from a loose or hanging wire.
yes, if I just tap the gas, it comes right back. . .


Quote:
Originally Posted by BDR561
Do you have a vacuum advance? Is it plugged into the right port on the carb? I have seen that mistake a few times with similiar results as you are experiencing
No vacuum advance


Quote:
Originally Posted by BNEWELL
thats too bad Rob. If one of my venders continually fails to provide support after the sale, I start looking for a new one. In my business, customer support is #1.

I hope you get it all worked out.
I'm not that concerned and it is not a real "problem", just needs some fine tuning that I want to learn how to do on my own.

Last edited by rsimoes; 07-23-2007 at 05:57 PM..
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  #24 (permalink)  
Old 07-23-2007, 06:00 PM
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Does it die like out of gas? or electrical shut off?
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  #25 (permalink)  
Old 07-23-2007, 06:22 PM
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Quote:
Originally Posted by rsimoes
Yeah, but he told me to call Quick Fuel. I did and they were no help. Kind of surprising.
With the money that you spent on your engine with Keith, I would get back on the phone, and I would talk directly to him (not one of his employees).

With as many engines as he builds for Cobras (and installs through his shop in TX) this is surely not the first time a customer has had this problem. He also needs to know that Quick Fuel was of no help at all to you.
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  #26 (permalink)  
Old 07-23-2007, 06:44 PM
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You probably have fuel running out of the vent tubes and flooding the motor.You can get longer vents from Summitracing.com and also lower the float levels to just below the sight glasses, the middle is too high.
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  #27 (permalink)  
Old 07-23-2007, 06:45 PM
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I have a pro systems carb that does the same thing.
It came with extentions & whistles, I've had the floats up & down without any noticeable difference. I now accept that I just have to blip the throttle when it occurs.
It is definately a sloshing problem & cleans instantly when the throttle is blipped.
I have noticed that the whistles do not seal very well in the jet blocks & considering sealing them with epoxy. at this point I am not sure the problem is serious enough to warrant it.
Please let me know if you find a solution.

Craig
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  #28 (permalink)  
Old 07-23-2007, 06:58 PM
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Quote:
Originally Posted by CHANMADD
You probably have fuel running out of the vent tubes and flooding the motor. You can get longer vents from Summitracing.com...
Or connect with a length of black rubber fuel hose that has a slot cut into the top of the "half moon". Old drag racers trick and easy to make/test.
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  #29 (permalink)  
Old 07-23-2007, 07:03 PM
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Pull the bowls off, and see what it looks like in there. We had big problems with Quick Fuel's carbs on the motor we built for my brother's Mustang this past winter. Quick Fuel actually misbuilt the carbs, and the floats were hitting the vent whistles. After we told them that, they replied that his carbs shouldn't have been built with vent whistles. Needless to say, after spending over $300 in shipping back and forth to Quick Fuel, the carbs never worked properly and we switched them out for a pair of Demons. They had their own issues, but were easily fixed and now the car runs awesome.
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  #30 (permalink)  
Old 07-23-2007, 07:55 PM
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And after you put in the whistles as three of us have suggested, get rid of the "sight glass". They are attacked by fuel, dry out and crack open. You may see the flames from the drivers seat if you're running. Seal your turkey pan to the hood.
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  #31 (permalink)  
Old 07-23-2007, 07:56 PM
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Maybe, I'll go with Holley, (more $$$ ) like I wanted from the beginning. . . I should listen to me more often. . .

I regreted every decision in which I didn't go with my instincts. . . hhmmm

Last edited by rsimoes; 07-23-2007 at 08:00 PM..
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  #32 (permalink)  
Old 07-23-2007, 10:05 PM
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Default Here is what I have been through

Had a Mighty Demon 850. Never ran right. Took about the bowls and discovered that a jet was laying in the bowl. The needle and seat was installed incorrectly. When I told the Demon rep about this he tried to blame it on Summit Racing and that they sold me a used Carb?!

Installed a Holley 830CFM, It ran better however not were it should be. Was stalling when I was slowing down to stop. Discovered the float was way too high and the squirters were too big.

Had Tom Barnard do the suspension. He told me he thought the carb was way too big for the application. 482 cubes which is street driven and opent track. No drag racing and that is a major point.

Had Bigs build up a 750HP stage five. Runs much better.

You should be 1000 to 1100 rpm at idle with your motor. Call Jessie at Bigs and Pat at Pro Systems and see what they have to say.
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Last edited by RedCSX1; 07-23-2007 at 10:19 PM..
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  #33 (permalink)  
Old 07-23-2007, 11:25 PM
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When you first touch the throttle does it start squirting or is there a little lag there? If blipping it makes it recover it's because it is either adding fuel to a starving motor or letting in air and recovering from a rich condition.
Jet extensions and whistles are cheap. Mine was doing the same type thing and after replacing the whistles it stopped. Turns out the one on the secondary was broken and not sealing on the bottom allowing fuel to slosh into the carb.
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  #34 (permalink)  
Old 07-24-2007, 07:27 AM
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The car runs perfect, outside of the unusual situations that make it stall. Just touching the gas squirts fuel in from the top. There is never a hesitation while driving.
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  #35 (permalink)  
Old 07-24-2007, 08:25 AM
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Sounds to me like you need the jet extensions. When you are on the brakes hard the fuel will slosh away from the primary jets.
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  #36 (permalink)  
Old 07-24-2007, 10:01 AM
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Quote:
Originally Posted by xlr8or
Sounds to me like you need the jet extensions. When you are on the brakes hard the fuel will slosh away from the primary jets.
I second that.

Very common problem with a simple fix.
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  #37 (permalink)  
Old 07-24-2007, 10:09 AM
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Obviously this Chaplin character is an intellegent guy.
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  #38 (permalink)  
Old 07-24-2007, 10:14 AM
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You never,never,ever use jet extensions on primary jets-----they are for use on the secondary side so fuel doesn't get away from the jets on hard acceleration when the engine needs it most!!!!!!
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  #39 (permalink)  
Old 07-24-2007, 12:31 PM
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I think I am going to pull the carb, crush it and install a Holley HP series 750 CFM and go for better low end drivability, since that's where I live. . .
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  #40 (permalink)  
Old 07-24-2007, 01:19 PM
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That isn't necessary---most drivability issues can be solved right in the base plate area---good fitting butterflies, properly blueprinted transfer slots--correct accerator pump setups, no vacume leaks,etc

The problem as you are representing it reminds me of others that I have seen that were set up and dialed in on dynoes---the carb guys build up a carb that should work well on the engine as spec'd---then the engine gets dynoed at 4500-7000 rpm with timing and jetting set up for max horsepower on dyno headers and RACE gas.

Then it gets installed into a car with different exhaust, an air cleaner, etc, and runs on PUMP gas at a much lower rpm and load.

Your problem is not that it dies as you come coast to a stop or turn a corner with the clutch in, but the fact that the engine WON"T idle with the clutch in without blipping the throttle. It doesn't need another carb, it just needs the carb you have and distributor to be set for a decent amount of driveability.

If your interested in more info, PM me and I'll give you an insight of a path to go down as I don't want to get into a carb contest here

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