Re: Cam break in is done!....Now more questions!
[Re: Kern Dog]
#1492848
09/01/13 10:30 PM
09/01/13 10:30 PM
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Joined: Mar 2008
Posts: 5,746 Ontario, Canada
Dodgem
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master
Joined: Mar 2008
Posts: 5,746
Ontario, Canada
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Spray brake clean or carb cleaner all around and see where the vacuum leaks are??? I use silicone on both sides of my intake gasket. where did you install the sensors for the O2??? Do you have another carb to try I think this one is wacked?? was it new or jerry rigged by someone?? You probably need a faster. Try holding you hand over cab to see if it idles better Maybe ulta lean had been your problem all along.
Last edited by Dodgem; 09/01/13 10:37 PM.
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Re: Cam break in is done!....Now more questions!
[Re: Kern Dog]
#1492849
09/01/13 10:34 PM
09/01/13 10:34 PM
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Joined: Mar 2008
Posts: 5,746 Ontario, Canada
Dodgem
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master
Joined: Mar 2008
Posts: 5,746
Ontario, Canada
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Air bleeds too big! Internal leak in the carb?? gasket under carb leaking?? intake leaking. is the cap on the big vacuum line at the back of the carb??? Your idle rally falls off N t D maybe needs lighter advance springs??
Last edited by Dodgem; 09/01/13 10:35 PM.
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Re: Cam break in is done!....Now more questions!
[Re: Dodgem]
#1492851
09/01/13 10:41 PM
09/01/13 10:41 PM
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Joined: Feb 2010
Posts: 18,493 Granite Bay CA
Kern Dog
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Striving for excellence
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Granite Bay CA
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Quote:
Spray brake clean or carb cleaner all around and see where the vacuum leaks are??? I use silicone on both sides of my intake gasket. I used "Gorilla Snot" gaskacinch.
where did you install the sensors for the O2??? I have a bung in each header collector, but only one sensor came in the guage kit.
Do you have another carb to try I think this one is wacked?? was it new or jerry rigged by someone?? The carb ran fine before I pulled it off for the cam swap. I only changed the 4 jets and Power valve.
You probably need a faster. ?????
Try holding you hand over cab to see if it idles better Okay, but it seems to idle fine. Its when I put a load on it that the guage goes LEAN.
Maybe ulta lean had been your problem all along. It looks that way. I'm going to UPsize the primaries to 88s and report back
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Re: Cam break in is done!....Now more questions!
[Re: Kern Dog]
#1492852
09/01/13 10:48 PM
09/01/13 10:48 PM
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Joined: Mar 2008
Posts: 5,746 Ontario, Canada
Dodgem
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master
Joined: Mar 2008
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Ontario, Canada
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squiters working right I think that 6.5 power valve must have be defective. This has me scratching my head. There is a transition from idle circuit to jets that is where the power valve is supposed to come in. You have the mufflers in I take it??
Last edited by Dodgem; 09/01/13 10:49 PM.
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Re: Cam break in is done!....Now more questions!
[Re: Baxter61]
#1492855
09/01/13 11:54 PM
09/01/13 11:54 PM
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Joined: Feb 2010
Posts: 18,493 Granite Bay CA
Kern Dog
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Quote:
Are you sure its not just out of fuel?
I've done that before!
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Re: Cam break in is done!....Now more questions!
[Re: Kern Dog]
#1492856
09/02/13 12:02 AM
09/02/13 12:02 AM
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Joined: Jan 2003
Posts: 5,446 Indiana
YO7_A66
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Indiana
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""The 88 jets now have the IN GEAR AT IDLE A/F at 16.0 to 16.8"" The jets do not control the In Gear Idle A/F. You are lean on the idle/transition circuits which consists of the Idle Air Bleeds and the Idle Feed Restrictors. The jets will affect the A/F further up the rpm range (cruising speeds)depending on how the carb is setup, not in gear at idle. You need to forget about the jets and concentrate on these two circuits before you burn up your motor. Once you get the idle circuit a little richer, then you need to concentrate on getting the off idle and low speed cruise richer too. Then once you get that under control, then revisit the main jetting.
""The gas here is "Up to 10% Ethanol."" You may want to aim for around mid to high 13's at the in gear idle with E10.
1970 YO7 A66 [Canadian Export] F8 Challenger 340 (Currently in shop for stroker assy.)
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Re: Cam break in is done!....Now more questions!
[Re: YO7_A66]
#1492857
09/02/13 12:16 AM
09/02/13 12:16 AM
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Joined: Feb 2010
Posts: 18,493 Granite Bay CA
Kern Dog
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Striving for excellence
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" You are lean on the idle/transition circuits which consists of the Idle Air Bleeds and the Idle Feed Restrictors. The jets will affect the A/F further up the rpm range (cruising speeds)depending on how the carb is setup, not in gear at idle."
So, could the lean readings I get when pressing the gas be attributed to the accelerator pump shot being too weak? I have a package of new pump cams I could try.
I have a Holley book here but it appears to be written for the guy that already knows carburetors better than I do.
Am I to understand that any and all jet changes shouldn't affect the guage readings at idle in Park?
I wish that I had some specs of what others used for their jetting. Cj wrote that he had 84/88 and the A/F ratios were right where he wanted them. My engine has a bit more compression and a lot more cam, so isn't it fair to think I'd need bigger jets than he used?
Last edited by Frankenduster; 09/02/13 12:20 AM.
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Re: Cam break in is done!....Now more questions!
[Re: Kern Dog]
#1492860
09/02/13 12:33 AM
09/02/13 12:33 AM
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Joined: Jan 2003
Posts: 5,446 Indiana
YO7_A66
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Indiana
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You need to start at the beginning on your tune. Since you have an auto, you want the most vacuum that you can achieve at your in gear idle rpms. With the brake applied (emergency brake or someone pushing on the brake), adjust your metering screws to obtain the best vacuum reading. Do no worry about the vacuum reading in N, you want the best vacuum reading in gear with the brake applied. You may need to work with your initial timing to get this vacuum reading up. Once you have your in gear idle vacuum reading at it highest, look at the A/F reading. This might be as rich as the 13's. After you get this set, then take it for a drive and watch the A/F readings at light throttle and cruising up to around 55-60 or so. Write down the A/F readings at the following: In gear idle (with brake) A/F= 30mph A/F= 40mph A/F= 50mph A/F= 60mph A/F= 70mph (if you drive at this speed) A/F= (If you are anything leaner than 15, then take it easy on the throttle so you don't hurt it!)
Once you take note of the A/F readings at these speeds, then you will be able to watch what happens at these same speeds when you make a tuning change in the future. Taking notes is the best way to keep track of your changes.
1970 YO7 A66 [Canadian Export] F8 Challenger 340 (Currently in shop for stroker assy.)
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Re: Cam break in is done!....Now more questions!
[Re: Kern Dog]
#1492861
09/02/13 12:35 AM
09/02/13 12:35 AM
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Joined: Jan 2003
Posts: 5,446 Indiana
YO7_A66
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Indiana
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Does this carb have screw in bleeds or are they just holes?
1970 YO7 A66 [Canadian Export] F8 Challenger 340 (Currently in shop for stroker assy.)
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Re: Cam break in is done!....Now more questions!
[Re: YO7_A66]
#1492862
09/02/13 01:19 AM
09/02/13 01:19 AM
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Joined: Feb 2010
Posts: 18,493 Granite Bay CA
Kern Dog
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Granite Bay CA
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Quote:
Does this carb have screw in bleeds or are they just holes?
Sorry, I'm not sure what this means. If you mean the idle mixture screws on the sides of the metering blocks, there are 4. One on each side of each metering block.
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