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Discussion Starter · #1 ·
I'm fairly new to carb tuning...I have the 200 CI I6, 3spd Tranny.

Okay...From searches, this is what I've found so far. A good place to start is to set the idle screw 2 complete turns from all the way in (but no too far). Advance to 6 degrees BTDC. I see 2 different screws, one in the front...one in the back on the passenger side. I'm thinking one in the front because it seemed to have more impact on my idle speed. THe one in the back effected it at high idle. Am I correct there?

Speaking of idle speed...what is the correct idle speed. I hooked up a tach/dwell meter today. The dwell was around 42 degrees (which is pretty close). The RPMs however were at 1300 (that is at normal idle). THat seems a little high. It sounds like it is running high. When I turn the idle screw in to slow it down...the lowest I can get it without the car cutting off is 1000. The timing information that I got said to run it down to 525 RPM. Why is the idle so high? How can I get it down to normal? What is normal idle?

When it is running at 1000 RPM, the timing is at 6 degrees BTDC, so I'm probably off at idle (and it sounds like it).

I think that is it for now. Thanks.

Slade
 
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Discussion Starter · #3 ·
Hi Jim,

First thing to do is square away the timing. Just shooting a light at it isn't the answer. You really need to remark the balancer. Balancers can and do shift surprising amounts throwing the amateur tuner for a loop. You can get in the balpark just by pulling the front plug and spinning the motor over by hand and try to pinpoint the piston dwell at TDC. Then, make you a new mark on the balancer @ 0* on the pointer. I'll betchya a quarter it's not where your original mark is at /forums/images/icons/wink.gif

That may solve you low speed idling problem. The engine will likely idle higher after you find you need to advance your timing. Then you can back the idle screw off. The idle mixture screw is on the passenger side. Turn it all the way in, then run it out until the engine runs at it highest rpm, then stop. Fine tune the idle with the speed screw on the drivers side of the carb.

John
PS - Check out www.fordsix.com if you have any more questions.
 

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You may have a vacuum leak. Check all the hoses and especially the gromment in the valve cover where the PVC goes in. PVC is okay right? Carb is secure on its mount? No vacuum leak there? I use 10 degrees BTDC (book says 12) for my car. I also have a new factory timing pulley.
 
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Discussion Starter · #5 ·
I'm going to really show my ignorance here...should the PVC be easily removable? I can pull mine right out with no problems...it just pulls right out. That doesn't seem right to me.

I do think I have a vacuum leak to the distibuter, I'm replacing the line today. I'll check some of the other areas today when I get home.
 
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