1974 Dodge Dart Magnum Swap

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HELP Please. I'm currently fitting headers and keep looking at the alternator. I fabbed up this alternator bracket from another alternator bracket. I really really don't like. What has everyone else used for a alternator bracket to their 360 magnum?

Apparently a couple of years difference makes a big difference, because I used literally everything from my 73 318 on the magnum. (all brackets and bolts) and everything fit like it was made for it.
The harmonic balancer is the only original magnum part on the front of the motor, and I had to egg out one bolt hole a little on it to use the LA lower pulleys.
 
I used all the stock brackets and pulleys on my 1978 truck.
I also compared the 1978 brackets to the ones on my 73 duster and they are identical.
 
I think the A/C style alt brackets don't match up with the raised mounts on the Magnum block/heads. All the bolt holes line up but don't sit right. I had that problem but when I got the no A/C brackets problem solved.
 
Thank you! Did you have to modify anything?
No. bolted it on, everything lined up good. I would use your old pulleys if your car was a V-8.
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No. bolted it on, everything lined up good. I would use your old pulleys if your car was a V-8.
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Awesome man thank you. I am still struggling with header fitment and hope to finish it up this weekend and have everything bolted in. As soon as it is nice weather I'd love to drive it. I had a baby in July so I have taken 5 months off and now I'm extremely anxious to get back at it.
 
Apparently a couple of years difference makes a big difference, because I used literally everything from my 73 318 on the magnum. (all brackets and bolts) and everything fit like it was made for it.
The harmonic balancer is the only original magnum part on the front of the motor, and I had to egg out one bolt hole a little on it to use the LA lower pulleys.
It must because all of my stuff came off a 82 Mirada. My car was originally a slant 6 car and converting to 5.9 magnum. I pulled everything off the 82 Mirada but a few things are off. The power steering pump bracket has one hole that won't line up and alternator bracket won't work at all.
 
Yeah I'm using all the old pulleys off my 318 so that might be the problem. The bracket I'm suggesting is just a reproduction of a stock piece. You might want to find a 70's small block to rob all the pulleys and brackets off of. Best no a/c to avoid the same problem. Your fabbed alt. bracket looks like 1/2 of my old bracket flipped upside down. It also may be you might have the wrong bracket for the PS pump you have. Federal/Saginaw and that may be why the holes are not lining up cause a small block Mopar should work with another SB Mopar.
 
Ended up bailing out on the headers and am in the process of cleaning up manifolds. As much as I hate to do it I seem to have no other choice other than going for some extremely high priced ones. I bought some Headman headers through summit and I can't get them to work. They come down right where the tie rod knuckle is and will not clear.
 
Fired it up for a few seconds last night for the first time. Sounds pretty damn good. Now all I gotta do is the finishing touches. I will try and post some pictures up soon.
 
Dude i just bolted the alt to the head with a long piece of SS 3/8" allthread and some nuts (jam nut stylie) to space it out. Used a generic universal for the slotted/bottom arm. $9 total, and i run kevlar belts from tsc for like $11 a pop.
 
It's been a while since I have posted. Have had the car up and driving over the summer but still have a few kinks to work out. I have a horrible vibration in the drive line some where that got worse when I switched my rear end gear ratio. If I shut my engine off as I'm moving the vibration stops. I'm thinking something in the flex plate weights is off. Either way here are a couple pics.

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I installed a 1999 5.9 Magnum, now a 408 in my 1975 Swinger. Used factory BRACKET, serpentine pulleys, water pump, alt. No PS. Use TTI headers. Factory 5.9 Compressor. With TTI's the # 7 cyl pipe is separate. Gives much more room. Also the trans fill tube clears. And don't forget the fuel line comes in from the back/right side of the engine. Used an electric fan assembly on this build, much cleaner and it cools here in Oklahoma heat.
Hope the photo helps with connections. Oh, forget heater hoses, they just get in the way.

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As for the vibration: Could be flex plate, harmonic balancer, or both.. Early 5.9 Magnums were externally balanced, later they were internally.
 
I put the magnum harmonic balancer back on it so not sure why it would be shaking. I will have to pull the starter and dust cover and look at the flex plate.
 
After pulling the trans 3 X. Had it disassembled and checked for all rotating pieces being straight and in balance, then Changed Flex plate 2X. Changed torque converter to a custom 3,000 stall, changed the Mopar balancer with another 5.9 Magnum balancer(both were new)with the same results. Vibration...
Save yourself the grief I encountered.. BUY a "Professional Products" Harmonic balancer.. Part # 80012. $97.00 from the distributor. They come with 3 sets of weights. They will work with all LA and Magnum engines. And, as I stated, early 5.9 EXTERNAL Balanced, Later 5.9 Internal balanced. Ask me how I know?? See above:)
 
"And, as I stated, early 5.9 EXTERNAL Balanced, Later 5.9 Internal balanced. Ask me how I know?? See above:)"

Ok I will ask how you know? Because none were internally balanced from the factory.
Although the pre-Magnum ('71-'92) and Magnum versions of the 360/5.9 are both externally balanced, the two are balanced differently (the 360 Magnum uses lighter pistons) and each requires a uniquely balanced damper, flywheel, drive plate, or torque converter.
 
Maybe this will help.. I had purchased a running 74 Scamp street racer with 5.9 Magnum. Ran perfect, no vibration. So, being a logical guy, I would used the same set up on my 408 (1999 5.9 Magnum originally). And all research indicated all 5.9's were ex. bal. When first fired up, vibration.. Ugh! That's when I went through the Stuff mentioned above.
I was told by the guy that builds the Torque converters that the later 5.9's were internally bal. We had a loud discussion about that at his shop. Which I disagreed with him, completely. This guy has been building converters for over 30 years. So, really what would he know that I didn't. Dah:)
Found the balancer on line and called, then ordered. Installed it, and WOW! No vibration.
The photos attached are of the flex plate that came with the Scamp. Date of manufacture: June of 2006. That plate is now obsolete. It can be used on early production motors along with the ex bal. balancer.
Again I hope this helps.

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I see, it was your 408 stroker that had a vibration. That is a whole new rotating assembly and requires its own balance be it internal or external. No parts off the original 360 magnum are going to work with that, they are meant to balance the weight of the 360 rotating assembly only. Maybe the converter guy is confused with the way the factory changed how they balanced 360 magnums, up to 95 the flex plate was neutral and the converter was weighted, 96 and newer the flex plate was weighted the converter was neutral, but the engine itself was always externally balanced.
 
I do not believe the converter guy was confused. I gave a friend the balancer from my Scamp(Magnum 5.9. Do not what year) do to his balancer starting to come apart. His 5.9 Magnum is in a 72 Charger. Do not know what year his Magnum is either. He called after installing it and stated that is was for an earlier Magnum. His was a" later motor". He happens to be a Dodge Mechanic. That was a couple of years before I had my 408 in the car. So I just blew it off and I got it back. My 408 is internally balanced. You can order the assembly Ex or Int balanced.
Again the best way to resolve the issue when building a 273/318/340/360la/5.2 magnum/5.9 Magnum ex or int balanced, or a 408 stoker ex or internally balanced LA or Magnum is to get the Professional Products Part #80012. For $97.00 you cannot go wrong..
It took me about 2 years to get all of this worked out do to different opinions. So, I am sticking to my story. :)
 
Yes, i agree, that balancer saves a lot of headaches being able to buy one to cover all the stock small block chryslers. Starting in 2000 the 5.9 magnum used a 1 piece pulley/balancer set up, that is the only difference between the older vs newer, so you believe what you want, there is no internal balance 5.9 magnum from the factory.
 
Well, lets leave it at this: You obviously know a lot about Mopar's engines and this discussion has covered a lot information WHILE PUNISHER66J was doing his build. I would not know a better way to providing so much information regarding this one issue.
I wish I would have had this information when I building my car.
Thanks for your expertise.
 
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