New DUI distributor questions
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Melting Slicks
Joined: Jan 2010
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From: Charlotte (Area) North Carolina
St. Jude Donor '11-'12-'13-'14
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New DUI distributor questions
I just got a new DUI distributor with new live wires. I have a sbc ,what can I expect from this new ignition set up? I currently have an accel dual point. I haven't had it installed yet but I was wondering if I will see or feel a big difference. I know it will be better than it is at the moment being I am only firing on 5 cylinders! Thanks for your comments 
Tech Contributor
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Well, obviously you will be noticing a great improvement in idle quality and drivability due to being able to run on 60% more cylinders (8/5). However, given that this is not an apples to apples comparison there's no way to quantify the improvement. Outside of some improved plug life and reduced distributor maintenance, the improvement will probably be minimal.
Melting Slicks
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Ian. Have you narrowed down your missfire to the dist.? What kind of shape is the dual point in and does it have a vac. advance? I know that the old school Mallorys did not have a vac. adv.. Maybe the guys can help you fix your current dist. if you want to return the DUI. I have access to many Chevy dist. but they are not likely to have a tach drive. I have a friend who has been hording them for decades. Let me know if I can help. mike...
Last edited by mds3013; Feb 26, 2011 at 11:24 PM.
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I just did an article for Auto Enthusiast magazine where we put a DUI HEI up against a full on MSD setup on a GM 572/720 12.0 compression motor in a 9 sec Malibu. Back to back at the track the DUI did VERY well. The 18volt box they have is a good addition also.
JIM
JIM
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Melting Slicks
Joined: Jan 2010
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From: Charlotte (Area) North Carolina
St. Jude Donor '11-'12-'13-'14
NCM Sinkhole Donor
Ian. Have you narrowed down your missfire to the dist.? What kind of shape is the dual point in and does it have a vac. advance? I know that the old school Mallorys did not have a vac. adv.. Maybe the guys can help you fix your current dist. if you want to return the DUI. I have access to many Chevy dist. but they are not likely to have a tach drive. I have a friend who has been hording them for decades. Let me know if I can help. mike...
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Melting Slicks
Joined: Sep 2010
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From: Emerald Isle NC
I have a dui in my 71. I think the biggest thing with it is peace of mind. No worries on point failure or lame "hei" retrofit modules. NEVER fails to start up, and quickly. Noticed the biggest difference on mine during non-braking deceleration. BTW, initial timing for me is at 15 deg. Yields the 52deg. "all in" timing per Lars G. et al. Install was a breeze. The one drawback...the livewires could stand to be longer. You have to do some kinda inventive routing/stacking. It's a little tight with a stock dual-snorkel breather, but not impossible...
Enjoy and lemme know if this helps, or you need more...
71scgc
Enjoy and lemme know if this helps, or you need more...
71scgc
Thread Starter
Melting Slicks
Joined: Jan 2010
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From: Charlotte (Area) North Carolina
St. Jude Donor '11-'12-'13-'14
NCM Sinkhole Donor
Did you get over the valve cover or under the header wires? I got under header ones, don't know if that will make a difference.
Melting Slicks
Joined: Sep 2010
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From: Emerald Isle NC
I got the unders also. It's the 1-4 cables that are a little short...Wasn't able to use the lower guards...Used cable ties to keep them off the exhaust manifolds (Ram-horns). Things are a little tight at the distributor too. A DUI is bigger than a stock GM HEI, and it's a little tight for the cables near the washer pump and the breather cover. I was able to "skip" the cables over the tops of adjacent plugs in order to get the clearances needed. Doing this has not caused any issues with the cables staying connected at the distributor. I've wondered if some stock-type HEI cables would solve these minor issues or not. That's a little too expensive of an experiment for me without some evidence that it could help things, especially minor things like these...
71scgc
71scgc
Le Mans Master
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From: B'Ville NY
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St. Jude Donor '05
I installed a mechanical tach drive DUI with under header Live wires. I could not believe the difference from this new setup compared to my old Mallory setup with an MSD box. It starts easier, idles better, improved throttle response. The improvement for my setup was more noticeable than expected. I sent DUI my specs and it was a plug and play when it arrived.
The only down side for me was that the large HEI cap interferred with my drop base air cleaner. I took a dremel to the air cleaner base and clearanced it so everything fits and most will never even notice the base edge lip modification if I don't point it out.
The only down side for me was that the large HEI cap interferred with my drop base air cleaner. I took a dremel to the air cleaner base and clearanced it so everything fits and most will never even notice the base edge lip modification if I don't point it out.
Thread Starter
Melting Slicks
Joined: Jan 2010
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From: Charlotte (Area) North Carolina
St. Jude Donor '11-'12-'13-'14
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They were short just like you said! It sucks when you pay a hundred bucks for "CUSTOM FIT" wires and they don't fit right! 
I will be calling on Monday to give them a piece of my mind. I doubt they will give a crap though! Anyway the car is purring like a kitten so i can't be too annoyed I guess! Thanks for the help!
I will be calling on Monday to give them a piece of my mind. I doubt they will give a crap though! Anyway the car is purring like a kitten so i can't be too annoyed I guess! Thanks for the help!
Thread Starter
Melting Slicks
Joined: Jan 2010
Posts: 2,416
Likes: 8
From: Charlotte (Area) North Carolina
St. Jude Donor '11-'12-'13-'14
NCM Sinkhole Donor
I still have it, I just think it was shot. The points were burnt out and it was time for a change. Anybody need a useless Accel dual point dist?