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Discussion Starter #1
Hey everybody, just wanted to introduce myself and ask a few questions. I live in Florida and my nephew just recently purchased a 1974 Space Duster in northern Georgia. This is his first car and we plan to work on it together and get it to where it needs to be. I have been collecting and working on muscle cars for quite a number of years and am a huge fan of mopars. My favorite car that I once had was a 71 340 Cuda and that, like I am sure many of you have experienced, wish I never got rid of it.

Anyway, back to the Duster. The car is in excellent shape with a slant-6 automatic and very little rust in the spare tire well. It is a 4-wheel drum car with 14" wheels with P225 70R14 tires. We would like to do a power disc brake conversion but I have been reading different issues with that. I read that you should only use original mopar disc brake parts like the spindles and calipers off of a doner. Also, I read I would have to replace the upper & lower ball joints because the current ones aren't strong enough and I might have to go with 15" wheels.

Does anyone know where we can purchase a complete power disc brake conversion kit and shed some light on any issues we might run into? Also, we are having a hard time finding anyone who sells parts for this car or any aftermarket factory stuff. I am in need of some interrior stuff too if anyone knows where I can get it.

Any input would be appreciated!

Mike & Drew


Whoops, sorry guys I just found another thread on this topic.

But, if anyone know where to get parts for these cars please let me know.

Mike
 

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Master Power Brakes and some others are advertised in every Mopar Muscle magazine issue. I used MP for my Demon. The kit included every single piece needed to do the job, from front brake lines, hoses, lower control arm, rotors, calipers, master cyl and prop valve. The job took only six hours and is very satisfactory in performance. The rotors and calipers are B body matching.
 

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DO NOT FEED THE TROLLS!
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Bear in mind, that if the current car is small bolt pattern, you'll need to deal with the rear hubs/brakes too so that you have one bolt pattern for the whole car.
 

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4 wheel drums on those were always small bolt pattern as I understand it. it's probably got a 7 1/4 rear axle under it too.
If I were doing it, I'd convert the front to discs and upgrade the rear axle to an 8 1/4 with the bolt bolt pattern at the same time, which means new brakes, new rear axle and new wheels.
There are disc kits that can retain the small bolt pattern, but if the car has a 7 /14 axle, it is the weakest link in the powertrain.
 

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Discussion Starter #5
Thanks to all for your input, I really appreciate it! I believe it does have the small bolt pattern and I am trying to do this as painless as possible. Since this is his first car we plan to leave the 6 banger in it for awhile until he learns more about working on them. That being said, at this point the weak 7 1/4" axles shouldn't be an issue at this point but definately a future upgrade.

If anyone would happen to know who carries a complete small bolt pattern disc kit I would appreciate the info on it. Also, where are you guys getting your parts for these cars, new or used?

Thanks,

Mike
 

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Don't count on the 7 1/4 surviving just because it's behind a Slant 6. Plenty of them have failed in that application (including the one in my 1968 Valiant).
 

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A '74 Duster should have 10-inch drums in front and 9-inch in rear. Yes, a disc swap in front would be nice but you must weigh all the pros and cons. Like posted above, you would also have to upgrade the small bolt pattern rear studs size and a '73 or later 8.25" drum to drum from a factory disc car is one way to go, but these are already very rare. However, depending on how much money you wish to 'invest' then consider upgrading the rear end to an earlier 8.25" unit with the small bolts AND 10-inch drums. You can always do the entire (large-bolt) swap at a later date but as long as slant six remains inside there is really no need for disc 'upgrade'. There were plenty of factory big blocks produced that came with 10 or 11-inch drums in the front (and 10's in rear). Just make sure all the hardware is functioning as expected and power-assist (for drums) is another upgrade to consider, if not there already. It wouldn't hurt to seek out a spare 7.25 unit to have on hand for parts as needed. A Sure-Grip is also available for the small rear and that will toughen up the tiny diff. immensely.

Oh, and you must know that small brakes and small rear-end are only two handicaps to consider. There is also the small (904) tranhy, small(19-inch) radiator and small(;860?-inch) torsion bars. But, on the good side, smaller parts contribute to lighter weight and that helps out performance and economy. Perhaps a nice set of (small bolt pattern) Argent Rallyes?
 

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Discussion Starter #9
Thanks again all, I didn't realize there were so many failure issues in the 7 1/4 rear. :pullhair: As some of you mentioned, I guess I should probably take a look at that sooner than later. I have been away from mopars for awhile but I know about the 904 though. Upgrades are in the works and it needs a little interrior work particularly on the headliner, door panels and carpet. The speedometer indicator was broken/missing so we found a replacement dash/gauge assy off of e-bay which is the only place I can seem to find parts for this right now. The gas gauge only reads half when full (sending unit), little issues like that so all-in-all a very solid project car.

I appreciate everybody's input and as I mentioned above, if anyone knows of any place where to get parts for these Dusters if you could please let me know?

Here is a pic of the engine compartment and car.

http://i304.photobucket.com/albums/nn194/mccuda/74DusterEngine_zps32debaf6.jpg

http://i304.photobucket.com/albums/nn194/mccuda/duster2_zpsa09b81ff.jpg
 

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Sometimes is it not the sending unit but the quality of the ground that can cause improper readings. You might try a jumper wire (even a test lead with alligator clips) to make sure there's a good ground at the tank before replacing the sending unit.

A great place for parts:
http://www.forabodiesonly.com/
i hate to refer you to another forum, but you'll find more parts in their for sale forums than anywhere else I've found. I've bough a few Valiant parts from members over there. Prices can be reasonable or expensive, just depends on the seller.
 

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The 7.25 is not that weak. I've had it behind my 300 HP 318 for over 10 years now without a problem. Change the diff oil and you shoud be fine with the /6.
 

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Where about do you live in FL? There are some very good Mopar friendly scrap yards in Sothwest Florida and central Florida. If it were me I would look for a Duster that already had disc brakes, like a 340 Duster. Some of the V8 318 cars had disc brake setups. Also I would not be so quick to give up on the drum brakes. The Duster is a light car and the braking with 4 wheel drums is respectable. Obviously nothing compares to disc, or 4 wheel disc or anti lock so on and so forth. The 7.25 rear end gets a bad rap but most of that comes from guys who flog them with a high horsepower V8 and they fail. The 7.25 is very reliable for everyday application and they do take some abuse. If you are going to upgrade to a 318, 340, 360 the disc brakes is probably a sensible change as well as the rear end. I agree that a 8.25 is less expensive and probably easier to find for an A body than a 8.75.
 

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Discussion Starter #13
I am in Titusville, 40 min east of Orlando but grew up in Tampa and still visit there often. I also have family in Tallahassee so I can pretty much cover the state if need be. Where are these scrap yards you are talking about? Most around here have crushed all the old stuff.

Thanks,

Mike
 
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