45 DCOE Webers on Automatic 12a
02-06-17, 12:01 PM
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45 DCOE Webers on Automatic 12a
After a couple weeks of digging and emailing known-good sources of information i am forced to start a new thread on a very well covered topic.
I am an FC guy, this is my first time mucking about with a carburetor. Its not my car but a co-workers fathers. The car sat for 5 years as the owner replaced a motor and did some other bits, to include 45 DCOE and MazdaTrix intake manifold and holley return AFPR. Car is otherwise stock.
When i got to the car the plug wires were in the wrong location and once we swapped those around and fed some starting juice into the carb she fired and ran VERY rich.
i did my best to tune the idle and mixture screws to get it to idle well and at an acceptable rpm. (I was shooting for 8oo or so) I got it feeling OK with a bit of stumbling but running and at our target rpm for idle. We then shifted from Park to Reverse and the rpms dropped under tick-over. In order to keep the car alive between park and reverse I had to set base(in P) idle at about 1.1k rpms. then as we shift in to drive the rpms drop to 800.
Due to the amount of adjustment needed I am assuming our jetting is off (jetting came with carb from second hand merchant). I got the following suggestion from MazdaTrix:
69 F9 Idle
190 main fuel
200 Air
F11 emulsion tubes.
I will switching to this jetting setup this weekend and will try again.
My question for the forum is this:
Does ANYONE have any suggestions about possible differences in carb tuning between trans types?
Can I accurately check and change ignition timing before I get the idle sorted out? I know the timing is at least close because we can start and drive the car, but i do not believe that it is ideal.
Admins; If you deem appropriate, could you move this thread to the most applicable and helpful section of the forum, Thank You.
Thank you to all who share some insight.
I am an FC guy, this is my first time mucking about with a carburetor. Its not my car but a co-workers fathers. The car sat for 5 years as the owner replaced a motor and did some other bits, to include 45 DCOE and MazdaTrix intake manifold and holley return AFPR. Car is otherwise stock.
When i got to the car the plug wires were in the wrong location and once we swapped those around and fed some starting juice into the carb she fired and ran VERY rich.
i did my best to tune the idle and mixture screws to get it to idle well and at an acceptable rpm. (I was shooting for 8oo or so) I got it feeling OK with a bit of stumbling but running and at our target rpm for idle. We then shifted from Park to Reverse and the rpms dropped under tick-over. In order to keep the car alive between park and reverse I had to set base(in P) idle at about 1.1k rpms. then as we shift in to drive the rpms drop to 800.
Due to the amount of adjustment needed I am assuming our jetting is off (jetting came with carb from second hand merchant). I got the following suggestion from MazdaTrix:
69 F9 Idle
190 main fuel
200 Air
F11 emulsion tubes.
I will switching to this jetting setup this weekend and will try again.
My question for the forum is this:
Does ANYONE have any suggestions about possible differences in carb tuning between trans types?
Can I accurately check and change ignition timing before I get the idle sorted out? I know the timing is at least close because we can start and drive the car, but i do not believe that it is ideal.
Admins; If you deem appropriate, could you move this thread to the most applicable and helpful section of the forum, Thank You.
Thank you to all who share some insight.
Last edited by NorthernForestMotorsports; 02-06-17 at 05:29 PM.
02-06-17, 04:29 PM
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i gave a cursory, safe for work, read of the FSM and did not see anything mentioned about a vacuum line from autotrans to carb. I will keep looking.
I did however read that i was setting idles wrong for the autotragic. That may be very helpful moving forward. Car must be shifted between N and D to have lean drop and various idle conditions tuned.
I did however read that i was setting idles wrong for the autotragic. That may be very helpful moving forward. Car must be shifted between N and D to have lean drop and various idle conditions tuned.
02-07-17, 07:24 AM
#6
Waffles - hmmm good
iTrader: (1)
Right, so any auto needs to know when to kickdown because of instant acceleration, thats usually
what the vacuum signal is used for to the tranny. Not sure if autos trigger idle changes when
shifted with the stock rats nest and nikki. You may just have to up the idle a bit to compensate.
As long as you don't have vacuum advanced hooked up on the dizzy and its around 1000 rpms
you can safely set the idle to factory specs. Mechanical advanced doesn't kick in until >2500
rpms I think. Depends on the year and dizzy. FSM has the info on when advances kick in.
what the vacuum signal is used for to the tranny. Not sure if autos trigger idle changes when
shifted with the stock rats nest and nikki. You may just have to up the idle a bit to compensate.
As long as you don't have vacuum advanced hooked up on the dizzy and its around 1000 rpms
you can safely set the idle to factory specs. Mechanical advanced doesn't kick in until >2500
rpms I think. Depends on the year and dizzy. FSM has the info on when advances kick in.
02-09-17, 02:46 PM
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Thanks again Kansas! TG Ill have to ask the owner if he ran that line when he swapped carbs. Thanks for your help, I had the hardest time finding the name of the vacuum line, only found it referencing it to the trans.