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limiting mechanical advance in MP dizzy? #791697 09/03/10 02:53 PM 09/03/10 02:53 PM
Joined: Nov 2005 Posts: 3,456 Fly Over States P PHJ426 OP master
PHJ426 OP master P Joined: Nov 2005 Posts: 3,456 Fly Over States	This is for a new MP RB distributor How much slot is required in an MP dizzy to get 18 to 20 degrees of crankshaft advance out of it? Or can I figure it out this way if the MP dizzy has an advance # stamped in it can I measure the slot length and divide by the number on the part? Then take that information and calculate the length slot I need for 18 to 20 degrees of mechanical I want? Thanks for the help.

Re: limiting mechanical advance in MP dizzy? [Re: PHJ426] #791698 09/03/10 03:09 PM 09/03/10 03:09 PM
Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually B BradH Taking time off to work on my car
BradH Taking time off to work on my car B Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually	Are you talking about the MP distributor w/ the Mallory-made adjustable advance mechanism? If so, Mallory makes (made?) an advance tuning kit w/ different diameter keys for setting the advance range, a selection of springs, and detailed instructions showing how each spring combination changed the rate of advance. I bought one years ago for setting up my MP/Mallory distributor.

Re: limiting mechanical advance in MP dizzy? [Re: BradH] #791699 09/03/10 03:49 PM 09/03/10 03:49 PM
Joined: Nov 2005 Posts: 3,456 Fly Over States P PHJ426 OP master
PHJ426 OP master P Joined: Nov 2005 Posts: 3,456 Fly Over States	Not sure if its the mallory unit or not. I bought the conversion kit this year so if mallory is supplying the distributors for them then I have one. From the outside can you tell a difference or do you have to dig into it to tell if its a mallory unit?

Re: limiting mechanical advance in MP dizzy? [Re: PHJ426] #791700 09/03/10 03:54 PM 09/03/10 03:54 PM
Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio Challenger 1 Too Many Posts
Challenger 1 Too Many Posts Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio	I don't know anything about the kits, but I have setup 3 of them so far. From my experience I wound up closing down the slots just under half way with 18 at idle and 35 total.

Re: limiting mechanical advance in MP dizzy? [Re: Challenger 1] #791701 09/03/10 04:57 PM 09/03/10 04:57 PM
Joined: Jan 2003 Posts: 17,914 S.E. Michigan ZIPPY I Live Here
ZIPPY I Live Here Joined: Jan 2003 Posts: 17,914 S.E. Michigan	Yep...usually just taking a good look at it and adjusting accordingly will get you where you need to go. If that seems like an odd thing to do or it doesn't seem to make any sense, the kit is P5153446. The kit is very nice, but it's like Pandora's box... it comes with 16 keys to measure the advance slots, and 15 different springs, and an instruction sheet that is the length of a short novel...so it's probably more than you actually need to get it in the ballpark of where you want it. Pull the rotor off....if the metal under the rotor looks like brass, it's the Mallory mechanism. If it looks like steel, it's the Chrysler mechanism. Rich H. Esse Quam Videri

Re: limiting mechanical advance in MP dizzy? [Re: ZIPPY] #791702 09/03/10 05:31 PM 09/03/10 05:31 PM
Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio Challenger 1 Too Many Posts
Challenger 1 Too Many Posts Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio	One thing I should add is, on the 2 MP dist that I bought new at the same time. Both pickup assys gave me trouble, the car would run fine at idle but when I drove it under load it would breakup and miss fire. Lot's of back fire and ran like crap. Of course I tried adjusting the air gap with my .007 brass feeler gauge. That did not help, what fixed the problem completely was replacement of the magnetic pickups with used one's I had in other stock dists. I still have those used pickups in there as I wanted to get new ones for them someday but haven't. I ohmed the pickups in my new MP dists before replacing them and both ohmed differertly than the stock used one's I had. Sucked when I first installed the dists because of this problem. I swear this happened on both of my cars, 340-440 But now I like the dist because the advance is so easy to adjust/change along with the advance curve. This was my experince with both a sb and bb dist. the third one I setup for a friend, I don't think he had that problem. I bought both mine at the same time around 2006 FWIW Adjust the slots about halfway closed and stick it in there. Set the idle timing at what you want and check the over all timing and adjust from there. I always take the dist out of the car and stuck it in a vise so I could make accurate adjustments. Get after it!!

Re: limiting mechanical advance in MP dizzy? [Re: Challenger 1] #791703 09/03/10 05:46 PM 09/03/10 05:46 PM
Joined: Nov 2003 Posts: 2,715 closer to Canadian beer! torkrules I'm neurotic
torkrules I'm neurotic Joined: Nov 2003 Posts: 2,715 closer to Canadian beer!	Quote: One thing I should add is, on the 2 MP dist that I bought new at the same time. Both pickup assys gave me trouble, the car would run fine at idle but when I drove it under load it would breakup and miss fire. Lot's of back fire and ran like crap. Of course I tried adjusting the air gap with my .007 brass feeler gauge. That did not help, what fixed the problem completely was replacement of the magnetic pickups with used one's I had in other stock dists. I still have those used pickup in there as I wanted to get new ones for them someday but haven't. I ohmed the pickups in my new MP dist before replacing them and both ohmed differertly than the stock used one's I had. Sucked when I first installed the dists because of this problem. I swear this happened on both of my cars, 340-440 But now I like the dist because the advance is so easy to adjust/change along with the advance curve. This was my experince with both a sb and bb dist. the third one I setup for a friend, I don't think he had that problem. I bought both mine at the same time around 2006 FWIW Ran into the same problem with the vacuum advance type distributors. Replaced the reluctor and pickup with one out of an old distributor. I bought the billet one and it worked fine. Same advance mechanics as the vacuum unit

Re: limiting mechanical advance in MP dizzy? [Re: torkrules] #791704 09/03/10 06:31 PM 09/03/10 06:31 PM
Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio Challenger 1 Too Many Posts
Challenger 1 Too Many Posts Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio	Quote: Quote: One thing I should add is, on the 2 MP dist that I bought new at the same time. Both pickup assys gave me trouble, the car would run fine at idle but when I drove it under load it would breakup and miss fire. Lot's of back fire and ran like crap. Of course I tried adjusting the air gap with my .007 brass feeler gauge. That did not help, what fixed the problem completely was replacement of the magnetic pickups with used one's I had in other stock dists. I still have those used pickup in there as I wanted to get new ones for them someday but haven't. I ohmed the pickups in my new MP dist before replacing them and both ohmed differertly than the stock used one's I had. Sucked when I first installed the dists because of this problem. I swear this happened on both of my cars, 340-440 But now I like the dist because the advance is so easy to adjust/change along with the advance curve. This was my experince with both a sb and bb dist. the third one I setup for a friend, I don't think he had that problem. I bought both mine at the same time around 2006 FWIW Ran into the same problem with the vacuum advance type distributors. Replaced the reluctor and pickup with one out of an old distributor. I bought the billet one and it worked fine. Same advance mechanics as the vacuum unit Yup, both of mine are vacuum advance units.

Re: limiting mechanical advance in MP dizzy? [Re: Challenger 1] #791705 09/03/10 10:26 PM 09/03/10 10:26 PM
Joined: Nov 2005 Posts: 3,456 Fly Over States P PHJ426 OP master
PHJ426 OP master P Joined: Nov 2005 Posts: 3,456 Fly Over States	Thanks for the info. I am pretty sure mine is a standard MP vacuum advance dizzy. So I will fill the slots in half way. The distributor was bought this year and the car runs fine no popping or backfire I just need to bring the mechanical advance down some.

Re: limiting mechanical advance in MP dizzy? [Re: PHJ426] #791706 09/04/10 09:10 AM 09/04/10 09:10 AM
Joined: Jan 2003 Posts: 1,022 Andrews,In. U.S.of A. 6 67_Satellite super stock
67_Satellite super stock 6 Joined: Jan 2003 Posts: 1,022 Andrews,In. U.S.of A.	I have an old (early 1990's)M.P. electronic and have done some mods to it. If you can measure the travel of the pin in the slot on the advance mechanism you can get pretty close to what you want. I have a set of "number" drills to measure the distance between the end of the slot and the pin. Not much room for calipers in there.I welded up one slot to limit total timing for boost and got it within 1 degree of my goal.After checking with a marked balancer and a timing light it works out to be 4 degrees at the crank for every .025" of pin travel. I set mine up with a .075 pin travel and got 12 degrees of advance. Add that to 12 inital for 24 deg. total to go with 10 lbs. boost.I also cheated and modified the vacuum adv. can to get a few more degrees out of it. You will need a welder and a dremel with some 1/8" or 3/16" diameter bits to do this though. If you don't already have them it may be cheaper to buy an adjustable dist.

Re: limiting mechanical advance in MP dizzy? [Re: ZIPPY] #791707 09/04/10 10:40 AM 09/04/10 10:40 AM
Joined: Jan 2003 Posts: 75,095 A Banana Republic near you. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 75,095 A Banana Republic near you.	Quote: Yep...usually just taking a good look at it and adjusting accordingly will get you where you need to go. If that seems like an odd thing to do or it doesn't seem to make any sense, the kit is P5153446. The kit is very nice, but it's like Pandora's box... it comes with 16 keys to measure the advance slots, and 15 different springs, and an instruction sheet that is the length of a short novel...so it's probably more than you actually need to get it in the ballpark of where you want it. Pull the rotor off....if the metal under the rotor looks like brass, it's the Mallory mechanism. If it looks like steel, it's the Chrysler mechanism. I bought the Mallory kit from summit, was pretty easy to adjust and the novel seemed like a short story , the hard part was getting the rollpin in the right place when putting the reluctor wheel back on.

Re: limiting mechanical advance in MP dizzy? [Re: 67_Satellite] #791708 09/04/10 10:47 AM 09/04/10 10:47 AM
Joined: Jan 2003 Posts: 4,296 Chicago, IL TonyS451 master
TonyS451 master Joined: Jan 2003 Posts: 4,296 Chicago, IL	Hey Paul, I bought my curve kit from jegs a few years ago. The jegs part number is 312-p513446, and its labeled as a Mopar part. My kit is mallory and Im pretty sure they are one in the same. Not sure how convenient it would be for you to pick up, but you're welcome to use my kit if you want. I set up my mp distributor with 16 degrees advance 20 initial and 36 total, and that seems to work pretty good. 2 kids and a dog

Re: limiting mechanical advance in MP dizzy? [Re: TonyS451] #791709 09/05/10 12:24 AM 09/05/10 12:24 AM
Joined: Nov 2005 Posts: 3,456 Fly Over States P PHJ426 OP master
PHJ426 OP master P Joined: Nov 2005 Posts: 3,456 Fly Over States	Im going to take the distributor out in the morning. Im 99% sure I didnt see any brass colored parts under the rotor. But we will see if I need the mallory kit or not after that. The local speed shop may have the mallory kit in stock. Thanks for all the tips on setting the mechanical advance.

Re: limiting mechanical advance in MP dizzy? [Re: PHJ426] #791710 09/05/10 02:13 AM 09/05/10 02:13 AM
Joined: Sep 2006 Posts: 3,011 Sac, CA M mopowers master
mopowers master M Joined: Sep 2006 Posts: 3,011 Sac, CA	FYI- I copies this from an old thread. It shows you how big to leave the slots for a given amount of advance. Quote: dist. degrees X 2 + initial= total dist. degrees / slot size 6.............. .340 7............... .355 8............... .375 9............... .390 10.............. .405 11.5 ........... .420 12.............. .435 13.............. .445 14.............. .460 15.............. .475 16.............. .490 17.............. .505 18.............. .520

Re: limiting mechanical advance in MP dizzy? [Re: PHJ426] #791711 09/05/10 04:02 AM 09/05/10 04:02 AM
Joined: Feb 2007 Posts: 2,315 MOPAR HEADQUARTERS IN ALDEN NY H hemigod426 top fuel
hemigod426 top fuel H Joined: Feb 2007 Posts: 2,315 MOPAR HEADQUARTERS IN ALDEN NY	ive got it dowm pat pretty much 1/4 of mig weld on both sides, grind flush both sides, reassemble track the curve. then rat tail file for the curve you want. its one of the most time consuming ones to recurve. but you gotta do it with any type of performance cam MOPAR OR NO CAR

Re: limiting mechanical advance in MP dizzy? [Re: hemigod426] #791712 09/09/10 06:09 PM 09/09/10 06:09 PM
Joined: Jan 2003 Posts: 9,892 Weddington, N.C. Streetwize master
Streetwize master Joined: Jan 2003 Posts: 9,892 Weddington, N.C.	FWIW....the old backyard hot rod trick we used to do was just wedge a small square of Mr Gasket white header gasket material into the outside of the slots to limit the pin travel, it sits in there tight and centrifugal force holds it in. Welding means you cant really turn it back to stock without having to ever grind it back out. in any event it's easy to try and see if it gets you where you want it without "fully committing". This way your centrifugal is limited and you run more initial, five minute drag strip tune that works every time. Remember the dizz only turns 1/2 the crank speed. My strokers like about 20-22 initial BTW. WIZE World's Quickest Diahatsu Rocky (??) 414" Stroker Small block Mopar Powered. 10.84 @ 123...and gettin' quicker! https://www.youtube.com/watch?v=-mWzLma3YGI In Car: https://www.youtube.com/watch?v=PjXcf95e6v0

Re: limiting mechanical advance in MP dizzy? [Re: Streetwize] #791713 10/15/10 10:14 PM 10/15/10 10:14 PM
Joined: Nov 2005 Posts: 3,456 Fly Over States P PHJ426 OP master
PHJ426 OP master P Joined: Nov 2005 Posts: 3,456 Fly Over States	Okay so I have been a little behind in getting this distributor done. I took it out this morning before work and took a look inside. I originally thought it was an old Mopar oe dizzy that would need the slots welded up. But the plate for the pickup is standard metal color. After removing the pick up it is apparent that the mechanical advance part of the dizzy is Mallory. Here is my question now: P5153446 is on back order with the local MP dealer I use. He can get me Mallory #29014 in the morning is this the same or do I need #29015 ? BTW my distributor was purchased this year in the electronic kit with the orange box wiring loom and all under PN P3690428. Anyone ever do this? What color springs did you use? I have a big block stroker on pump 93 in a heavy street B body. How do you use the stick looking parts? Do you loosen the adjusting screws and make the opening windows for the mechanical advance slots smaller? I think it will be pretty cool to use this kit instead of having to weld up the slots and grind out what you dont need. Thanks for the advice.

Re: limiting mechanical advance in MP dizzy? [Re: PHJ426] #791714 10/15/10 10:28 PM 10/15/10 10:28 PM
Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio Challenger 1 Too Many Posts
Challenger 1 Too Many Posts Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio	Quote: Do you loosen the adjusting screws and make the opening windows for the mechanical advance slots smaller? Yes

Re: limiting mechanical advance in MP dizzy? [Re: Challenger 1] #791715 10/15/10 10:49 PM 10/15/10 10:49 PM
Joined: Nov 2005 Posts: 3,456 Fly Over States P PHJ426 OP master
PHJ426 OP master P Joined: Nov 2005 Posts: 3,456 Fly Over States	After doing some searching on the net it does look like 29014 is the correct Mallory pn for the advance kit. Here is a link to the instruction sheet http://www.malloryperformance.com/pdf/29014.pdf

Re: limiting mechanical advance in MP dizzy? [Re: PHJ426] #791716 10/17/10 11:15 PM 10/17/10 11:15 PM
Joined: Nov 2005 Posts: 3,456 Fly Over States P PHJ426 OP master
PHJ426 OP master P Joined: Nov 2005 Posts: 3,456 Fly Over States	After using the kit wow, I have to say its really easy to adjust the mechanical advance on the unit. No need to take the unit farther apart past taking the hall effect sensor plate off to change the springs and no need to take the distributor completely apart to weld up them slots.

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