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amount of vacum @idle ? #912979 01/24/11 05:37 PM 01/24/11 05:37 PM
Joined: Dec 2010 Posts: 35 north palm florida united stat... M mopar0723 OP member
mopar0723 OP member M Joined: Dec 2010 Posts: 35 north palm florida united stat...	1970 440+6 engine bored 030 stock spec cam 292 duration 590 lift how much vacum should I have at idle say 800 rpm /vacum gauge hooked to rear of intake.

Re: amount of vacum @idle ? [Re: mopar0723] #912980 01/24/11 06:16 PM 01/24/11 06:16 PM
Joined: Jan 2006 Posts: 1,220 toronto canada 69chargeryeehaa pro stock
69chargeryeehaa pro stock Joined: Jan 2006 Posts: 1,220 toronto canada	20in ish....

Re: amount of vacum @idle ? [Re: mopar0723] #912981 01/24/11 06:31 PM 01/24/11 06:31 PM
Joined: Oct 2003 Posts: 996 Queens, New York H Harley super stock
Harley super stock H Joined: Oct 2003 Posts: 996 Queens, New York	Quote: 1970 440+6 engine bored 030 stock spec cam 292 duration 590 lift how much vacum should I have at idle say 800 rpm /vacum gauge hooked to rear of intake. 292/590 lift is far from stock. If that is the cam you are running, i would think more like 12 to 14 inches of vacum.

Re: amount of vacum @idle ? [Re: Harley] #912982 01/24/11 06:37 PM 01/24/11 06:37 PM
Joined: Dec 2010 Posts: 35 north palm florida united stat... M mopar0723 OP member
mopar0723 OP member M Joined: Dec 2010 Posts: 35 north palm florida united stat...	I only have 7-8 not shure what to do first

Re: amount of vacum @idle ? [Re: mopar0723] #912983 01/24/11 06:45 PM 01/24/11 06:45 PM
Joined: Oct 2007 Posts: 3,884 Oregon hooziewhatsit master
hooziewhatsit master Joined: Oct 2007 Posts: 3,884 Oregon	What's your initial timing at? If you ever find yourself in a fair fight, your tactics suck.

Re: amount of vacum @idle ? [Re: hooziewhatsit] #912984 01/24/11 06:47 PM 01/24/11 06:47 PM
Joined: Dec 2010 Posts: 35 north palm florida united stat... M mopar0723 OP member
mopar0723 OP member M Joined: Dec 2010 Posts: 35 north palm florida united stat...	initial is @ 10.5

Re: amount of vacum @idle ? [Re: mopar0723] #912985 01/24/11 07:09 PM 01/24/11 07:09 PM
Joined: Jan 2003 Posts: 1,996 s. e. pa. C calrobb2000 top fuel
calrobb2000 top fuel C Joined: Jan 2003 Posts: 1,996 s. e. pa.	hi 9 in with that cam no more prob? idle speed for a six pack is 900 rpm ! what is your actual comp ratio or cranking compression psi ??

Re: amount of vacum @idle ? [Re: calrobb2000] #912986 01/24/11 07:36 PM 01/24/11 07:36 PM
Joined: Dec 2010 Posts: 35 north palm florida united stat... M mopar0723 OP member
mopar0723 OP member M Joined: Dec 2010 Posts: 35 north palm florida united stat...	all I know on motor is it has six pack pistons, bored 030 over, the cam stated above, my problem is as follows = tried to solve before but ran out of time had to go, anyway when I set idle @ say 800 then blip throttle @ carb then let go it will not return to 800 settles back in @ 1050-1150 and will not go back to 800 unless you loosen idle screw and start over. I did disconnect cable to rule out to tight, also checked for hang up. However when I do same test with vac hose disconnected from dist, idle returns to 800ish. Idle does jump around 20 -30 turns on the digital Tach/timing light, it is new. several guys said look hard at my distributor it is the mopar performance electronic dist ( very old 11+ years or so ) carbs are all redone.

Re: amount of vacum @idle ? [Re: mopar0723] #912987 01/24/11 07:48 PM 01/24/11 07:48 PM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	Quote: will not go back to 800 unless you loosen idle screw and start over. However when I do same test with vac hose disconnected from dist, idle returns to 800ish. Idle does jump around 20 -30 turns on the digital Tach/timing light, it is new. several guys said look hard at my distributor What did you mean 20-30 turns? What they said, open up the dist, take out the center clip/pry up the reluctor & see what you see w the plate/arm assy that's out of whack EDIT b 4 you open the dist pump up the can & see if it's hanging up (rare)/leaking (somewhat common) Last edited by RapidRobert; 01/24/11 07:52 PM.

Re: amount of vacum @idle ? [Re: RapidRobert] #912988 01/24/11 07:59 PM 01/24/11 07:59 PM
Joined: Dec 2010 Posts: 35 north palm florida united stat... M mopar0723 OP member
mopar0723 OP member M Joined: Dec 2010 Posts: 35 north palm florida united stat...	when watching rpm on gun (digital) rpm will fluctuate about 30 rpm if set @ 800 fluctuates between 780 - 810 normal ? as far as the distributor goes if I buy a new one of the same one I have, should it be good to go without adjusting anything inside distributor.I do not know if anything has changed with them in the 11+ years. I just do not know anything about distributors or anyone around here that I trust to work on it. thanks

Re: amount of vacum @idle ? [Re: mopar0723] #912989 01/24/11 08:06 PM 01/24/11 08:06 PM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	Quote: if set @ 800 fluctuates between 780 - 810 normal ? Actually yes as I forgot that you have a cam. It MAY need a higher idle speed to stabilize. EDIT after (re) reading I dont think it's a dist prob. I would set the (initial)timing via the vac gauge method then shorten the slots to get 36-38 total then play w the springs (more on that later) then dial in the vac adv (more on that later). You will need to find the idle speed for that cam that is stable (maybe higher than 800) and I am not a 6 pack guy but they (the carbs) MAY or may not need mods for a wild cam Last edited by RapidRobert; 01/24/11 08:19 PM. live every 24 hour block of time like it's your last day on earth

Re: amount of vacum @idle ? [Re: RapidRobert] #912990 01/24/11 08:46 PM 01/24/11 08:46 PM
Joined: Sep 2005 Posts: 12,481 Chino Valley RodStRace I Live Here
RodStRace I Live Here Joined: Sep 2005 Posts: 12,481 Chino Valley	The OE 6 packs idled at ~1100 and had a solenoid to shut the blades when turned off. That's a fairly big street cam (yeak, someone is going to come on and say 700 is big), so idle vacuum is going to be low and you will want the idle up a bit. Problem is dropping it into gear if auto. Here are a few things to try. Make sure the timing is rock steady at idle. There is a "hose trick" in the tech archives. Make sure the vacuum and cent. advance isn't coming in. 1100 is usually enough to uncover the ported vacuum. You can try to open the outboards a bit. This is a balancing act. Now that you have a solid timing at idle, with nothing creeping in, make sure there are NO vacuum leaks and the throttle blades and shafts are tight and not hanging.

Re: amount of vacum @idle ? [Re: mopar0723] #912991 01/24/11 09:02 PM 01/24/11 09:02 PM
Joined: Feb 2005 Posts: 4,313 Prospect, PA BSB67 master
BSB67 master Joined: Feb 2005 Posts: 4,313 Prospect, PA	Quote: 1970 440+6 engine bored 030 stock spec cam 292 duration 590 lift how much vacum should I have at idle say 800 rpm /vacum gauge hooked to rear of intake. Your statements regarding the cam do not make sense. There is no stock cam with specs anywhere near what you've posted. Is it possible that it is a Mopar 292/509 cam?

Re: amount of vacum @idle ? [Re: RodStRace] #912992 01/24/11 09:12 PM 01/24/11 09:12 PM
Joined: Dec 2010 Posts: 35 north palm florida united stat... M mopar0723 OP member
mopar0723 OP member M Joined: Dec 2010 Posts: 35 north palm florida united stat...	Yea I can not set car @ 900 rpm, where it probably should be, it is a 4 speed. as soon as I turn idle up and get to about 870-880 it just takes off to the 1050-1150 as stated above and stays there, then have to loosen idle screw to get it back down, only does this if vac adv hose hooked up,won't do this if I plug, but I want it hooked up and it all to work the way it is supposed to. I do not know what else to try before buying a new distibutor.

Re: amount of vacum @idle ? [Re: BSB67] #912993 01/24/11 09:16 PM 01/24/11 09:16 PM
Joined: Dec 2010 Posts: 35 north palm florida united stat... M mopar0723 OP member
mopar0723 OP member M Joined: Dec 2010 Posts: 35 north palm florida united stat...	yes you Are right I typed in the wrong numbers that is the cam in the motor 292/509

Re: amount of vacum @idle ? [Re: mopar0723] #912994 01/24/11 09:22 PM 01/24/11 09:22 PM
Joined: Jul 2006 Posts: 4,179 California mickm master
mickm master Joined: Jul 2006 Posts: 4,179 California	Quote: Yea I can not set car @ 900 rpm, where it probably should be, it is a 4 speed. as soon as I turn idle up and get to about 870-880 it just takes off to the 1050-1150 as stated above and stays there, then have to loosen idle screw to get it back down, only does this if vac adv hose hooked up,won't do this if I plug, but I want it hooked up and it all to work the way it is supposed to. I do not know what else to try before buying a new distibutor. get a vacuum pump gauge on the vacuum advance. disconnect the hose at the carb, and plug the gauge in there. take off the distributor cap, and see at what level of vacuum the plate starts to rotate. sounds like it is set very low, and is advancing as soon as you hit the 800 rpm range or so. i don't know about the older distributors, but with the newer ones you can stick a small allen wrench in the hole on the vacuum advance canister where the hose plugs into. with that, you can loosen or tighten the springs on the vacuum advance, so it comes in with more/less vacuum, as needed by your situation.

Re: amount of vacum @idle ? [Re: mopar0723] #912995 01/24/11 09:30 PM 01/24/11 09:30 PM
Joined: Jan 2003 Posts: 1,758 Windsor, ON, Canada D Diplomat360 top fuel
Diplomat360 top fuel D Joined: Jan 2003 Posts: 1,758 Windsor, ON, Canada	Quote: Yea I can not set car @ 900 rpm, where it probably should be, it is a 4 speed. as soon as I turn idle up and get to about 870-880 it just takes off to the 1050-1150 as stated above and stays there, then have to loosen idle screw to get it back down, only does this if vac adv hose hooked up,won't do this if I plug, but I want it hooked up and it all to work the way it is supposed to. I do not know what else to try before buying a new distibutor. To me that sounds like a vacuum can adjusted with way too little tension...that means it'll come on quicker...you may be getting some interaction between the vac can and the distributor mechanical advance. Namely, the vac can kicks in...the idle speed jumps up, the dist goes into the mech advance curve...etc....the dead giveaways is that this does not happen with the vac can disconnected. Toss in an alan wrench into the nipple and tighten it up...so that it comes on at a higher vacuum signal.

Re: amount of vacum @idle ? [Re: Diplomat360] #912996 01/24/11 09:45 PM 01/24/11 09:45 PM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	Quote: Toss in an alan wrench into the nipple and tighten it up...so that it comes on at a higher vacuum signal. 3/32" allen wrench, turn it CCW live every 24 hour block of time like it's your last day on earth

Re: amount of vacum @idle ? [Re: mopar0723] #912997 01/24/11 09:50 PM 01/24/11 09:50 PM
Joined: Feb 2005 Posts: 4,313 Prospect, PA BSB67 master
BSB67 master Joined: Feb 2005 Posts: 4,313 Prospect, PA	Quote: yes you Are right I typed in the wrong numbers that is the cam in the motor 292/509 This is a big cam. Add the six pac, low compression and 10 degrees initial timing and 8" sounds right. Although I have not had this combination myself. Personnally, I would skip the vacuum advance for now, it is just one more variable. You can put it back later. Get your initial timing to be 20 degrees and steady (not advancing) to at least 1200 rpm. Then check for vacuum leaks at the carbs and intake manifold. Then use a vacuum gauge to adjust each carb. That will get you started.

Re: amount of vacum @idle ? [Re: BSB67] #912998 01/24/11 11:11 PM 01/24/11 11:11 PM
Joined: May 2005 Posts: 2,295 dark side of the moon D Dougsmopars top fuel
Dougsmopars top fuel D Joined: May 2005 Posts: 2,295 dark side of the moon	10 degrees timing is not enough. As memtioned bump it up to 20, bring it up as high as possible with no ping and no hard start hot. Mine likes 22 degree. Recurve the dizzy to keep total advance to 38.

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