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Hi,
Need some advice on jetting/adjustment of carb. Just got my AEM wideband guage installed. At an idle of 950-1000 it's ranging from 13.2-14. Once you give it some gas to simulate cruising (2500 or so) it drops down in the 10's. The motor is a .030 over 454, 9.6 compression, Merlin oval port heads that have been ported, Comp cams hydraulic flat tappet extreme energy xe274. The carb is an AED 950hp. I changed the idle air bleeds from .070 to .078. It has 78 primary jets and 86 secondary jets. I'm trying to get it tuned so it will quit fouling plugs and run the best. It has a MSD pro billet distributor with a 6al box. the timing is set at 18 initial and 36 total. The intake is an Edelbrock Performer RPM. It's still winter here in the midwest, so I can't really go out and see what the reading is for wot. Do I need to put smaller jets in at least the primaries? What size should I go with?
 

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Running 2500 in the garage is not the same as 2500 crusing, and a 950 is kinda large
unless it's a track only car, an 800 or so, would give better driveability.
I agree with John, you can't get a handle on the afr unless you drive it on the road, with varying vacuum which will affect the afr. I installed the same AEM guage and hooked it to my laptop to monitor the afr at different engine loads because the readings change so much. It took quite some time changing jets and playing with the idle mixture to get it in the right ballpark, but worth the effort. I got a surprising 16.5 mpg on a trip and I don't worry about damaging my engine or fouling plugs.
 

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1st off dump the O2 gauge....waste of time and doesnt have the logging response time
Get a O2 logger like the innovate LM1 or 2...
You also need the rpm input.

And there is a thread a couple months ago where a member went from...put bluntly "thick" on the subject, and walked thru his carb tuning.

If you have a 'track' engine on the street there is no way you will get it to run or idle as well as a engine designed for the street....hence why when on is in the pits, track engines when ticking over are so bloody rich it makes your eyes water.

And you are wasting your time if the timing curve, intial, cent, and VA are not in the ball park 1st.

And youhave very clear in your head a carb is basically 3 separate carbs in one
a/ idle circuit
b/light load cruise circuit
c/WOT circuit
And the accelerator pump to transition between them.

This may help you also
http://firstgens.com/forum/34/o2-sensor-on-old-school-cars-1669.html
 
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