Need help with a '66 Dart

[duaneparks]

I'm sure there are a few on here who have experience with older Mopars... and I need your advice.



My mom has a '66 Dart, /6, auto, etc. It needs the diff oil changed. Will 75/90 work? Or, should I use something different? The vehicle will be driven in Southeast Texas, so the ambient temp range will be 30* to 100*F.



Vehicle has 61K original miles on it, and it has the original drivetrain. Thanks!



Duane



On edit, I can spell, and wanted it to reflect in the post.

 

[Headshot zod]

I can't remember. Look up 66 darts on Google. There must be a mopar site that would have that info. Actually an autoparts store could look it up for you. When are you going to put a 4cyl cummins in that thing?

 

[Philip]

75/90 will work alright.

 

[MFalkinham]

Try posting your question on the www.moparts.com Q&A forum. Those guys know everything about vintage Chrysler iron.



- Mike

 

[moparguy]

75/90 is great. I'd only use dino though.



RJR

 

[catoiler]

That thing ain't got enough horsepower to turn 85/140!! Really though the 7 1/4 rear is just fine with the 75/90. If you ever go to a small block be sure to dump that rear and go with an 8 3/4 as it wont be long before the spider gears go south. Want to buy a 13. 0 sec slant 6 for it?

 

[Hohn]

I agree that 75-90 is fine, and I'd stick with Dino, too.

On something that old, you're likely to have axle seal leaks if you switch to syn. Mopar axles are VERY easy to rebuild as far as seals go, so you could go that route if you wanted.

Odds are that the car has the tiny 7 1/4" Mopar diff-- a pretty fragile unit, but it can easily handle a /6.

Catoiler is right. The trick is finding a "small" bolt pattern 8 3/4-- very hard to come by. You could always pickup a B-body 8 3/4 and have it narrowed. Then you have a LOT more options as far as gearing and traction aids.

Personally, I think an older A body like your Dart is a PERFECT car to do the stroker small block thing with the new mopar 4" stroke crank. There are a lot of pistons on the market now for both 340 and 360 strokers, and there are a handful of pistons for the 318 bore size. This crank gives between 390 cubes (in a 318 bore) and 408 cubes (340 bore).

The rod ratio is still useable at 1. 53 or so. It's a good street combo capable of 600hp in more aggressive trim.

That's enough to make a 2800 lb A body FLY!

Justin

 

[catoiler]

Hohn,Our 63 A body wagon turns 10. 80 with a 360. The new motor should push it into the high 9's on just the motor. As far as the small bolt 8 3/4 I still have a few of them but I am going to the big bolt as their is more wheel/tire combos.

 

[Hohn]

Sweet, I've ben wanting to build a stroke LA engine with the small chamber W2 heads. Those things scream with 13:1 compression and a relatively mild cam.

Justin

 

[catoiler]

The Brodex heads we are running on the new motor flowed 341/220. The cam is being ground and should be pretty wild. We are keeping the CR at 12. 8 Thought about runing a turbo but there is not a whole lot of room. How far is Cheyenne from Sheriden?My newphew lives there and we might go up there next year.

Mike

 

[HEMI®Dart]

Hey Guys,



I just recently picked uo a '68 Dart GTS. Original 383 car, now a 440. I will probabley need some tech support once I tear into it. Lots of stuff I want to change.

 

[MFalkinham]

Hey Guys,



I just recently picked uo a '68 Dart GTS. Original 383 car, now a 440. I will probabley need some tech support once I tear into it. Lots of stuff I want to change.

You're a lucky man! Back in 1986 I had a chance to buy a '68 Dart GTS for $1,600 from a guy who really needed the $$. The original 383 had been replaced by a 340, and the rear axle was bad, but otherwise it was in very clean original condition. At the time I did not have a way to haul it nor a place to store it, so I ended up passing on the opportunity. To this day I'm still kicking myself for "the one that got away". :{



- Mike

 

[Hohn]

The Brodex heads we are running on the new motor flowed 341/220. The cam is being ground and should be pretty wild. We are keeping the CR at 12. 8 Thought about runing a turbo but there is not a whole lot of room. How far is Cheyenne from Sheriden?My newphew lives there and we might go up there next year.



Mike

It's quite far. Everything around here is spaced far apart. You're welcome to swing through and hang out a bit if you wish.



JLH

 

[duaneparks]

Thanks guys for the info. After putting 75/90 in it, I dragged the car from Knoxville to Houston on Saturday behind a (Cummins powered) motorhome. Never even knew the car was back there. Tomorrow I'll try to post a pic or two of her in my gallery. I love these old Mopars!



Bill, that '68 is just downright COOL.

 

[duaneparks]

For anyone interested, there's a new pic of the '66 in my gallery...



Duane