If you're blowing caps off of ANY 8 3/4, it's time to move up to a Dana.
742 vs 489 Case
- Thread starter USCG CHARGER
- Start date
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dusterdragracer
Drag Racer
72BBSwinger:
Now that's what I am talking about! Real life experience, rather then bench racing and theroy!
Nice car, looks like my wifes except she has a white top.
Have a great day.
Chris
Now that's what I am talking about! Real life experience, rather then bench racing and theroy!
Nice car, looks like my wifes except she has a white top.
Have a great day.
Chris
dusterdragracer
Drag Racer
To Stockerscamp:
Only blew caps off 489 case, never on 742 case.That is the point.
Dana too heavy
Only blew caps off 489 case, never on 742 case.That is the point.
Dana too heavy
72BBSwinger
Well-Known Member
My 318 4speed 70 Power Wagon didn't need a Dana.
Then something was wrong with the 489.
72BBSwinger
Well-Known Member
There was, weak *** caps......
vitamindart
Well-Known Member
489 vs 742 is all opinion.... i like the 742 no crush sleeve
and for those who think the 489 is So much better Why did mopar use the 742 when they made an aluminum version?
and for those who think the 489 is So much better Why did mopar use the 742 when they made an aluminum version?
Because as of then, there was no crush sleeve eliminator for the 489. With the eliminator, the 489 is the strongest, but it's all a stupid *** arguement, because the difference in strength between all THREE is minimal. I've seen 9 second cars with the 741 season after season. They are all within a fraction of each other, so it's ghey to keep arguin over it.
vitamindart
Well-Known Member
i agree, the diference is minimal. i have run all three at one time or another. if they are set up right and taken care of they all will work.
Map63Vette
Well-Known Member
Yeah, it doesn't matter how thick the pinion is if they all have a step transition in the diameter, that's going to be the weak point every time aside from some defect in the metal. The only reason I'd consider changing from my 741 is because you can barely buy any gears for it. The only choices I have found so far are 3.55 and 3.73.
Joe Dokes
Well-Known Member
I had a chance to buy a 741 A-Body 8 3/4 for $800.00 and passed for a few reasons. 1. Didn't have a Sure Grip, 2. Had 3.23 Gears, wanted 3.73-4.10 3. limited gear availability.
I still haven't decided to what rear to run. I KNOW that an 8 3/4 can be built strong enough to survive my HP and Torque projections of 500HP and 420 FT/LBS of torque. That's not the problem, the problem is finding an 8 3/4 at a reasonable price.
I can buy Ford 8.8 with 3.73-4.10 Gears and disc brakes for 100.00 at pick a part during a 1/2 price weekend. So I'm thinking of going this route. There are Mustang Guys running low 9s with an 8.8. so I know it will survive too.
The only issue I have with the 8.8 is that it is a Ford part.
As for a Dana, I have to agree, it might simply be too heavy. If I were running a 500+ cubic inch Hemi with 600+ FT/TQ and a trans brake I'd run a Dana, but at this point, the Dana seems like over kill.
Regards,
Joe Dokes
I still haven't decided to what rear to run. I KNOW that an 8 3/4 can be built strong enough to survive my HP and Torque projections of 500HP and 420 FT/LBS of torque. That's not the problem, the problem is finding an 8 3/4 at a reasonable price.
I can buy Ford 8.8 with 3.73-4.10 Gears and disc brakes for 100.00 at pick a part during a 1/2 price weekend. So I'm thinking of going this route. There are Mustang Guys running low 9s with an 8.8. so I know it will survive too.
The only issue I have with the 8.8 is that it is a Ford part.
As for a Dana, I have to agree, it might simply be too heavy. If I were running a 500+ cubic inch Hemi with 600+ FT/TQ and a trans brake I'd run a Dana, but at this point, the Dana seems like over kill.
Regards,
Joe Dokes
If you do go that rout (but please don't, don't need terd junk in our mopars lol
) get one out of an explorer. They have 31 spline axles, larger bearings & axle tubes, common with 3.73 & lower ratios with ls, and there are millions of them in junk yards. I just swaped one of those in my Ranger thats getting a 2.3l turbo out of an '87 thunderbird for those reasons listed but thats cause its a ferd so it gets ferd parts :glasses7:
Phordpar. Ghey.
dusterdragracer
Drag Racer
Fact:
O.K. So I run my car, and on the 4th pass, I leave on the converter with no chip (5,000) and 8 LBS of tire pressure. I was practicing for an AFX class we will be running that uses the 4 teenths Pro Tree. So with the pictures I attached. This is what 440 + rear wheel H.P. does to a 489 case.And it is back braced. I rest my case about the 489 case. They have never worked for me, and this is the 2nd car I blew the caps off one. I am switching to a 742.Believe what you want, poof is in the pudding. And yes, I will be running the street gears, because there are no Pro gears for 8 3/4's, unless you want to run 4:89's.
Lastly, no one can figure what happened, did the Caps blow 1st then the ring and pinion went or visa versa. I would say it blew the ring and pinion, and caused a wedgie, which broke the caps. And by the way, everything was new and set up correct. There is just something about the quality of the 742 case webbing. It is plain stronger. If yours is holding up,good for you. For me, I don't trust them in a race application.
By the way, no one is trying to argue. Just put plain simple proven proof being put out there, for those that want to know, and try and save them grief and money.
http://www.facebook.com/media/set/?...05419780814.2121260.1421974018&type=3&theater
http://www.facebook.com/media/set/?...05419780814.2121260.1421974018&type=3&theater
O.K. So I run my car, and on the 4th pass, I leave on the converter with no chip (5,000) and 8 LBS of tire pressure. I was practicing for an AFX class we will be running that uses the 4 teenths Pro Tree. So with the pictures I attached. This is what 440 + rear wheel H.P. does to a 489 case.And it is back braced. I rest my case about the 489 case. They have never worked for me, and this is the 2nd car I blew the caps off one. I am switching to a 742.Believe what you want, poof is in the pudding. And yes, I will be running the street gears, because there are no Pro gears for 8 3/4's, unless you want to run 4:89's.
Lastly, no one can figure what happened, did the Caps blow 1st then the ring and pinion went or visa versa. I would say it blew the ring and pinion, and caused a wedgie, which broke the caps. And by the way, everything was new and set up correct. There is just something about the quality of the 742 case webbing. It is plain stronger. If yours is holding up,good for you. For me, I don't trust them in a race application.
By the way, no one is trying to argue. Just put plain simple proven proof being put out there, for those that want to know, and try and save them grief and money.
http://www.facebook.com/media/set/?...05419780814.2121260.1421974018&type=3&theater
http://www.facebook.com/media/set/?...05419780814.2121260.1421974018&type=3&theater
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