Help destroyed 7 1/4 in a /6 dart

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1964dart4speed

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Hi guys I'm new and also newly the proud owner of my grandpa's 1964 dodge dart 270 with a factory 225 and matching 4 speed that stranded me thanks giving day exploded spider years did a new set broke those to and am sick of breaking them a this is my daily driver I would like to d an 8 1/4 swap the only reliable lead I have on them is late 80s early 90 dakotas and cherokees anyone know if they would be good fit thanks and have a great day
 
1964dart4speed said:
Hi guys I'm new and also newly the proud owner of my grandpa's 1964 dodge dart 270 with a factory 225 and matching 4 speed that stranded me thanks giving day exploded spider years did a new set broke those to and am sick of breaking them a this is my daily driver I would like to d an 8 1/4 swap the only reliable lead I have on them is late 80s early 90 dakotas and cherokees anyone know if they would be good fit thanks and have a great day
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Welcome to FABO. I will move this thread to the drivetrain forum. If you are looking for someone here that has a used one for you to buy you will need to start a wanted thread in the proper classified forum.
 
You’d be better off finding a 73-76 A Body 8.25 - other than driveshft shortening, it’s a virtual drop in. Cherokee/Dakotas will require some mods - perches, shortening, etc. Are you planning on upgrading to LBP on the front to match the back? No, then I would see about finding a 65-72 A Body 8.75 with SBP axles.
 
They generally hold up well behind slant sixes. Are you snatchin it around when you shift? They're not made for all that. They are a light duty rear end and will hold up if driven correctly.
 
RustyRatRod said:
They generally hold up well behind slant sixes. Are you snatchin it around when you shift? They're not made for all that. They are a light duty rear end and will hold up if driven correctly.
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Or one wheel burnouts at 6000 rpm. LOL
 
toolmanmike said:
Or one wheel burnouts at 6000 rpm. LOL
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That's normally what makes spider gears give it up. People don't stop to think one wheel burnouts cause the spider gears to spin TWICE as fast as when both tires spin. That's some incredible RPM. They're simply not made for that. That'll even kill open Dana 60s and 8 3/4s.
 
1964dart4speed said:
no i baby the car fresh rebuild the engine isnt even broke in yet
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Then I suspect you had something wrong. Although they are a light duty rear axle, they will hold up pretty well behind a slant six. Plenty of people have had them with V8s and abused them and they lived, so that leads me to believe there's a problem somewhere. You sure you get it full of gear oil?
 
I ran one behind a 340,
in a 65 Valiant wagon,
for two or maybe more summers I think it was.
When I blew the 904, I gave it to my little brother, who swapped out the 340/904 for me, and put a 225/904, that I supplied, into it, and then he drove it some more. I still have that 340/904, some 45 years later.
Hang on, confession time;
That 340 had a 318 top end on it and a 318 cam in it. So it was really just a big-bore 318, but man it was wicked.
 
RustyRatRod said:
Then I suspect you had something wrong. Although they are a light duty rear axle, they will hold up pretty well behind a slant six. Plenty of people have had them with V8s and abused them and they lived, so that leads me to believe there's a problem somewhere. You sure you get it full of gear oil?
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yeah i had it full but i still want a stronger unit so i dont have to worry about it breaking in traffic luckly both times were close to my house abd on quite streets but imagine i went to take off from a stop light in rush our traffic id get creamed
 
yeah i ve considered it just looking for the best donor vehicle you know closest measurements and my point was those would shatter behind a 4 banger it doesn't help I've got an extra few hp on top of what Mopar intended for it
 
1964dart4speed said:
yeah i ve considered it just looking for the best donor vehicle you know closest measurements and my point was those would shatter behind a 4 banger it doesn't help I've got an extra few hp on top of what Mopar intended for it
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Yeah but it's still a slant six. A 7 1/4 in good shape would handle all but the most severe abuse.
 
First: Welcome to FABO!! Its really exciting to see a young guy like you getting into these old cars!!

Definitely put a wanted ad on FABO for a rear, there may be someone close to you. Follow @65 Dartman advice and bolt it in!!
 
i have a 1964 dart with a 225 4 speed 3.55 in a 7.25 beat on that littler bastard day and night no problems, i even had a 318 stock 4 speed and 7.25 beat on that all day too until i sold it. Honestly i would go with a 8.75 rearend with small bolt pattern axles its going to be the same work with any rearend need to shorten the shaft, shock plates.

Theres a guy who sells the housing abody cut to fit on ebay for 250.00 get some Small bolt pattern axles 75.00-100.00 bucks, backing plates 100.00, shock plates $100.00 then hardware new drums, and gear set of your choice i picked up 3.91s for 100.00 on craigslist. $600.00-700.00 got yourself a solid rearend. lol
 
1964dart4speed said:
ok um also are there any gm rear ends that may fit? im open to anything that may fit
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I'm not sure how "MANY". The spring perch distance is 43" center to center, I believe. If I remember right, the flange to flange width is 51 5/8". Don't take that as gospel, because I'm old. I'm sure one of these guys will correct me if I'm wrong.
 
Slantsix64 said:
i have a 1964 dart with a 225 4 speed 3.55 in a 7.25 beat on that littler bastard day and night no problems, i even had a 318 stock 4 speed and 7.25 beat on that all day too until i sold it. Honestly i would go with a 8.75 rearend with small bolt pattern axles its going to be the same work with any rearend need to shorten the shaft, shock plates.

Theres a guy who sells the housing abody cut to fit on ebay for 250.00 get some Small bolt pattern axles 75.00-100.00 bucks, backing plates 100.00, shock plates $100.00 then hardware new drums, and gear set of your choice i picked up 3.91s for 100.00 on craigslist. $600.00-700.00 got yourself a solid rearend. lol
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That's really not bad!
 
Welcome aboard! Sounds like your going to need help with Grandpas Dart.
You've been given good advice, I would suggest you take it, you could be in over your head quickly with Grandpas Dart and your dad sitting and rusting.
I threw out a 7 1/4 recently. They are out there cheap.
Good luck.
 
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