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 Post Posted: Fri May 11, 2012 9:50 am 
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Location: Greensburg, Pa
Okay I backed out the idle speed screws and scribed a line then measured from the line to the bottom of the t slot. Primary was .055, sec .058 from the line to the slot. This also works out to 2 turns on the idle screws to the bottom of the slot and another half turn gives .020 of slot showing.

When I turn in a corner screw all the way it will slow down and kill the motor.


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 Post Posted: Fri May 11, 2012 10:09 am 
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Location: Montgomery, Alabama
Ok it sounds like we have a good baseline now.
Now mark your speed screws so you know exactly where they are. Turn them in 1 turn each and go from there.

BTW,
The slot does not have to be exposed on a dominator.
The blade is big enough in OD to work without being exposed.
Try to get it to run without worrying about Tslot exposure.

Just get your Idle RPM/Fuel mixture happy and lets go from there.


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 Post Posted: Fri May 11, 2012 10:30 am 
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I will try that tonight, I didn't have the slot exposure before the conversion.


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 Post Posted: Fri May 11, 2012 12:27 pm 
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There is more than one way to skin a cat to get Tslot exposure if needed. ;-)

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 Post Posted: Fri May 11, 2012 7:05 pm 
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I figured i needed to find a direction so i took the new plugs out andback on n with the black ones, i also went down to a .035 ij, and .078 iab and bumped timing back up to 38. Throttle responce seemed lean and had to go out 3 turns. Then i changed the iab to.067 and took it for a ride which helped clean the plugs up alot but it was lean in 2000-3000 cruise. I only have .052 in the t slot so i will bump it up some next.

I ended up with two turns on the primary idle screw even with the bottom of t slot, and 1.5 on the secondary almost to the t slot. If i unlocked timing i could probably get the slot if i have to.

I ended up 2 turns out on the corner screws.

Does this seem out of line or unusual?


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 Post Posted: Fri May 11, 2012 9:39 pm 
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This suggestion might be out in left field but do you have another engine you could try this carb on or have a friend that would run it to see if it's the carb?

When I did mine I was lucky as I have another car that I could and did run mine on just to see how it did. That "other" engine was a POS 355 pump gas engine with a small hyd cam but that 1050 of mine ran fine on that engine also?? Oh, and this is a street car too. I have that carb on that thing now but now it's a 434 pump gas roller engine instead of that POS 355.

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 Post Posted: Sat May 12, 2012 8:53 am 
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Wow I don't know what to say. I thought we were going to work on the idle quality and the next thing I know we are driving down the street and swapping idle jets and changing air bleeds....... O:) O:) O:)

I can't keep up. [-( [-(


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 Post Posted: Sat May 12, 2012 10:25 am 
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Location: Greensburg, Pa
Ken i like the idea of trying it on another car but the ones with dominators are on alcohol, but i will do some checking.

Scott sorry man thought the idle jet and idle bleeds were idle quality [-( . I tried the .035 ij since the .040 keept sooting up the plugs and the exhaust was burning the eyes. I will put the .040 back in if you want. The ride wasn't planned, i was almost out of gas so i went and filled it up since my cans were full of 87 octane from fuel perks.


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 Post Posted: Sat May 12, 2012 10:43 am 
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The idle jet supplies fuel to the Tslot and Idle circuit.
The idle mixture screw is a smaller restriction than the idle jet.

You need to get the idle quality correct before worrying about anything else.

If your getting a big swing in RPM from Neutral to gear your idle is not correct.

Turning the mixture screws is for idle mixture and nothing else.


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 Post Posted: Sat May 12, 2012 10:46 am 
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Quote:
I ended up with two turns on the primary idle screw even with the bottom of t slot, and 1.5 on the secondary almost to the t slot. If i unlocked timing i could probably get the slot if i have to.


Why not keep the front and rear even on speed screws and idle mixture screws?


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 Post Posted: Sat May 12, 2012 7:48 pm 
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Location: Greensburg, Pa
I am starting to think the rich idle is from me adjusting the idle mixture screws wrong after reading your post. I could kill the motor with the.040 ij in bye turning one screw in all the way, now that tells me that bye turning all of them in a little i should be able to lean out the idle. Where i was screwing up was adjusting them out so it had good throttle responce, sounds like i need to adjust them and the idle speed screws so it idles clean and not worry about throttle responce with this adjustment.

I didn't get to work on it today but i will tomorrow. Yesterday the rpm would drop 200 from neutral to in gear.


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 Post Posted: Sat May 12, 2012 10:30 pm 
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No you never adjust idle mixture for throttle response.


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 Post Posted: Sat May 12, 2012 10:48 pm 
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If you get better throttle response by over richening the idle screws it means your tslot circuit is either not flowing enough at idle position or its too lean on the T slot restrictor.


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 Post Posted: Sun May 13, 2012 9:19 am 
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Location: Greensburg, Pa
Now you guys got me understanding the functions of these circuits, i was off on that [-( . Today i will set the the carb back to the starting specs and work on the idle screws and see where that puts the throttle blades/ t slot exposure.

It sounds like the next part will be t slot exposure and t slot restrictor after i get straightened out on the mixture screws. I will update today.
Thanks george


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 Post Posted: Sun May 13, 2012 11:12 am 
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I'm assuming you dont have an o2 sensor?

You can use a vacuum gauge and tune idle for best vacuum and get close. The final test is it shouldn't change much rpm at all from neutral to in gear.

Turn all screws evenly. As RPM increases from leaning back off on speed screws. Same thing, keep both speed screws the same.

After that is perfect then you should move on to the next step (off idle)

When the engine is cold it should require a little pedal to keep it running since there is no choke.


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