Previous Thread
Next Thread
Print Thread
Page 2 of 2 1 2
Re: 440 running lean on cyl 7&8 with 6 bbl? [Re: 72demon416] #2496766
05/16/18 09:19 AM
05/16/18 09:19 AM
Joined: Feb 2005
Posts: 28,312
Cincinnati, Ohio
Challenger 1 Offline
Too Many Posts
Challenger 1  Offline
Too Many Posts

Joined: Feb 2005
Posts: 28,312
Cincinnati, Ohio
When my 440 6 pack did that I did not have enough timing. Fried a nice set of TTI headers.

Re: 440 running lean on cyl 7&8 with 6 bbl? [Re: Challenger 1] #2496857
05/16/18 03:43 PM
05/16/18 03:43 PM
Joined: Aug 2011
Posts: 2,853
Pattison Texas
CSK Offline
master
CSK  Offline
master

Joined: Aug 2011
Posts: 2,853
Pattison Texas
Originally Posted By Challenger 1
When my 440 6 pack did that I did not have enough timing. Fried a nice set of TTI headers.


^^^^^^


1968 Charger COLD A/C Hilborn EFI
512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim
2020 T/A 392 Stock 11.79 @ 114.5

Re: 440 running lean on cyl 7&8 with 6 bbl? [Re: CSK] #2496898
05/16/18 05:38 PM
05/16/18 05:38 PM
Joined: Jan 2003
Posts: 10,696
North Dakota
6PakBee Offline
I Live Here
6PakBee  Offline
I Live Here

Joined: Jan 2003
Posts: 10,696
North Dakota
Do you have power brakes? If so disconnect the hose, cap the fitting in the manifold and see if that makes a difference.


"We live in a time when intelligent people are being silenced so that stupid people won't be offended".
Re: 440 running lean on cyl 7&8 with 6 bbl? [Re: 72demon416] #2497500
05/18/18 12:09 PM
05/18/18 12:09 PM
Joined: Jan 2003
Posts: 4,711
Moved to N.E. Tennessee
GomangoCuda Offline
master
GomangoCuda  Offline
master

Joined: Jan 2003
Posts: 4,711
Moved to N.E. Tennessee
Quote:
I have the center jetted at 64 and 1.5 turns out on the bleeds right now and set the outboards by covering the idle air bleeds and setting the mixture so that there was no change in rpm covered or uncovered. That worked out with the front base idle screws out about 1.25 turns and the rear carb wanted them closed right off- but these are idle settings anyways so I don’t see that having any bearing on my lean part throttle issue anyways.....or am I wrong on that?


Several people have tried to explain to you that the front and rear idle mixture screws have to be set the same. 3/8 to 1/2 turn out from seated is typical. Do not try to set the front carb for best idle first. When you do that it is trying to feed idle fuel to all 8 cylinders from one carb which is why you wound up at 1.25 on it and then the rear wanted nothing. You have to adjust both carbs at the same time. I know it is a pain but when you think about it it makes perfect sense. Again, 3/8 to 1/2 turn out from seated on both carbs is typical not 1.25. Forget about the finger over the bleed trick. It is BS that was first printed in the early to mid 70's and repeated a 1000 times since then. Please forget you ever saw it.

You never said what your initial and total timing is. This is critical. If you don't have enough timing at idle then you will wind up with the idle speed screw adjusted in too far. That will expose too much transfer slot and then the center carb will feed too much fuel and you will probably try to correct it at the mixture screws. You will be chasing your tail. You need 18 deg or more at idle before you ever start trying to set anything in the carbs. You will probably need to recurve the distributer to maintain the correct total timing.


In theory, there is no difference between theory and practice. In practice, there is.
Re: 440 running lean on cyl 7&8 with 6 bbl? [Re: 72demon416] #2498161
05/20/18 11:24 AM
05/20/18 11:24 AM
Joined: Mar 2008
Posts: 193
Sharpsburg Maryland
4
440farmer Offline
member
440farmer  Offline
member
4

Joined: Mar 2008
Posts: 193
Sharpsburg Maryland
How do you get in touch with Bob weaver
To get those idle screws and tool?
All I get on the Internet is 6pac abbs
Any body got a link?

Re: 440 running lean on cyl 7&8 with 6 bbl? [Re: GomangoCuda] #2499834
05/24/18 03:11 AM
05/24/18 03:11 AM
Joined: Jun 2004
Posts: 1,496
Sask, Can.
7
72demon416 Offline OP
pro stock
72demon416  Offline OP
pro stock
7

Joined: Jun 2004
Posts: 1,496
Sask, Can.
I see I missed some replies over the last week or so I figured I’d update this a bit for those that were trying to help.
I walked away from this for a while to install my shaker hood and do the bodywork but tonight I decided to tinker a little more. For those wondering, There has never been any vacuum hoses connected and my initial timing was at 15 so I bumped it to 18 and overall it ran super really... except for the one idle screw that was still not functioning. My secondary’s at 1 turn out were rich enough that closing the primary idle screw would not kill it so I decided that I better have another look at the center carb and close up the secondaries a bit. I closed up the secondaries to 1/2 a turn out but there just wasn’t quite enough fuel to sustain a idle and the center carb didn’t provide enough fuel with the one operational idle screw so off it came again. The first thing I looked at was how much idle transfer slot was showing and it is literally picture perfect- until i opened the blades more and saw the one slot is not really a slot at the top, it almost looks like the side of the slot is broken out in a triangle shaped break. I don’t know if it’s a casting flaw or not but it gradually opens up to AT LEAST twice it’s normal width. This is on the side the idle screw does not function, so given that this problem exists and that the throttles blades weren’t even centered on the shaft, not allowing them to close initially, I think it’s time to give Holley a call and see if there is warranty on it. This carb appears to be a reject in quality control.
We’ll see how this goes...

Page 2 of 2 1 2






Powered by UBB.threads™ PHP Forum Software 7.7.1