Moparchat - Home of MOPAR enthusiasts worldwide!



Go Back   Moparchat - Home of MOPAR enthusiasts worldwide! > Technical Forums > Performance Talk

Click here to search for Mopar cars and parts for sale.


Reply
 
Thread Tools Display Modes
  #1  
Old 10-17-2002, 01:42 PM
Cliff Foster Cliff Foster is offline
Inactive User
 
Join Date: Apr 2002
Location: Phnx, AZ
Age: 52
Posts: 426
Default 8-3/4 or 9-1/4 Which do you recommend?

I am Looking at beefing up my 8-1/4 rear end in my ext-cab dakota with stronger axles, limited slip, etc... What I want to know is if it's worth the many dollars$$$$$ I am going to spend to buy a new or used 8-3/4 or a new 9-1/4 rear with the same internal upgrades. I don't do much racing at all, but I will see the track about once a week or two with some hard starts and a little street racing (shhhhhhh). I want to make sure that when I do want to race on the strip with slicks that I'm not breaking stuff and calling a wrecker. I think that the prices for the rears are all about the same or somewhere in the same neighborhood.
Reply With Quote
  #2  
Old 10-17-2002, 01:54 PM
Doug Wilson Doug Wilson is offline
Inactive User
 
Join Date: Aug 2001
Location: Sheridan, Oregon
Age: 79
Posts: 2,510
Default

If you have the budget, I'd go for an 8 3/4 with some decent axles. If you are using slicks, I think you may break the one you have.
Reply With Quote
  #3  
Old 10-17-2002, 02:00 PM
Doug Wilson Doug Wilson is offline
Inactive User
 
Join Date: Aug 2001
Location: Sheridan, Oregon
Age: 79
Posts: 2,510
Default

In terms of severe usage, and parts availability, here would be my approach:

1) Dana 60 - spendy - very hard to break - lots of ratios - lots of parts available

2) 9" Ford - cheaper than Dana - all other stuff above applies

3) 8 3/4 - cheaper than Ford - pretty strong - lots of stuff available

4) 9 1/4 - strong, spendy, not lots of stuff available

5) everything else

Is it possible that not everyone agrees with me???
Reply With Quote
  #4  
Old 10-17-2002, 02:02 PM
The Dartman's Avatar
The Dartman The Dartman is offline
Inactive User
 
Join Date: May 1999
Location: Bettendorf, Iowa, USA
Age: 53
Posts: 579
Default

Umm... Cliff racing "once a week or two" is a lot of racing especially with "a little street racing" in between. When I say "I don't do much racing at all" I mean around 5 times a year!!

Anyway, you probably already realize that the Dana 60 is arguably the strongest rearend around. What you may not know is that the 8 3/4 is also considered to be the third strongest rearend behind the Dana 60 and PHord 9 inch. The drawbacks with the Dana is that the gear and differential unit are hard to swap for your everyday Joe. If you have a true dual purpose vehicle, you want to be able to switch the gear without breaking a sweat. The Phord 9 inch and 8 3/4 both allow you to easily slip in a 4.88 gear with a spool, and the next weekend run a 3.55 with a sure grip. The Dana parts are considerably harder to find, and more expensive that the 8 3/4, plus finding a Dana in the right width will be harder than finding a 8 3/4 with the right width.

It also depends on what the truck will run too. I assume this may be a 13, 12 or even 11 second ride by your specs (a couple of funny things in there though), which is tempered by the fact that this is a street truck. If this is true, the 8 3/4 is well up to the task of handling all the power needed to run these numbers in your truck. However, a ten second or less truck would need the dependibility of the Dana to handle all that power. If you ran tens, I assume you would have said it right off... that's nothing I could even hold back!!

Let's hear some current ET's before I commit any further...

Dartman
Reply With Quote
  #5  
Old 10-17-2002, 02:05 PM
The Dartman's Avatar
The Dartman The Dartman is offline
Inactive User
 
Join Date: May 1999
Location: Bettendorf, Iowa, USA
Age: 53
Posts: 579
Default

Doug:

Isn't the Dana 60 and 9 1/4 the same thing? I guess I've spent my years looking at too many 8 3/4's, cause I always thought so.

Hmmm...
Dartman

PS - I've setup a ton of 8 3/4's and quite a few 10 and 12 bolt GM's, but I don't think I've ever had my mitts on a Dana.
Reply With Quote
  #6  
Old 10-17-2002, 02:23 PM
Doug Wilson Doug Wilson is offline
Inactive User
 
Join Date: Aug 2001
Location: Sheridan, Oregon
Age: 79
Posts: 2,510
Default

If it is, I must be drunk again.
Reply With Quote
  #7  
Old 10-17-2002, 04:34 PM
caveman caveman is offline
Inactive User
 
Join Date: Jan 1999
Location: Penfield NY USA
Posts: 318
Default

The Dana is 9 3/4,the 9 1/4 is a truck rear end.And they are pretty strong,you would have to narrow it to fit a Dakota.There is a Co that custom makes 9 1/4 rears with 8 3/4 axles out there.Cant remember what there name is though.For what your doing the 8 1/4 may not be a bad choice,there are tons of them out there cheap.Not are'nt the strongest unit but they can take plenty of abuse,gears and Limited slip are available
Reply With Quote
  #8  
Old 10-17-2002, 04:53 PM
Mopardad's Avatar
Mopardad Mopardad is offline
Inactive User
 
Join Date: Jan 2001
Location: Manheim Pa.
Posts: 177
Default

Doug, the 9" Ford may be more popular than a Dana but when it comes to building a qualiity rear the Dana is much cheaper to build. The Ford 9' also takes more power to turn because of the hypoid distance.
also to answer the topic question the 8 3/4 while not quite as strong as the 9 1/4 is a much better rear, the reasons =
9 1/4 use a C clip for axle retenion ,if you break a axle you are probably going for a ride, try finding a suregrip for a 9 1/4 at a reasonable price, try finding decent gears for a 9 1/4, most likely any 9 1/4 housing would need to be narrowed to fit your Dakota & if you are going that route you might as well put in a Dana it would cost about the same money.
Reply With Quote
  #9  
Old 10-17-2002, 05:37 PM
Doug Wilson Doug Wilson is offline
Inactive User
 
Join Date: Aug 2001
Location: Sheridan, Oregon
Age: 79
Posts: 2,510
Default

I really don't think that it's cheaper to acquire and build a Dana than a 9" inch - maybe it depends on how you approach it.

I can't do my own work, so I have to pay for everything.

Can you tell me how much it would cost to build a limited slip, 4.88, to fit an early A body, for each one - brake drum to brake drum?
Reply With Quote
  #10  
Old 10-17-2002, 06:43 PM
caveman caveman is offline
Inactive User
 
Join Date: Jan 1999
Location: Penfield NY USA
Posts: 318
Default

The 9 is cheaper,and much lighter than a Dana,if you did some homework 1 out a Torino/mustang might be close to what you want in width(just a guess),parts are available used and new.The Co that puts the 8 3/4 axels in the 9 1/4 eliminates the c clips.The rear is plenty strong.I saw this in an old mopar action mag.Its a nice swap,and would out last the truck in my opinion.But if it were me I would find a ford guy,and find a used rear end housing,drop in a pumpkin and go
Reply With Quote
  #11  
Old 10-17-2002, 07:59 PM
rumblefish360's Avatar
rumblefish360 rumblefish360 is offline
Moparchat Bronze member
 
Join Date: May 2000
Location: C
Age: 57
Posts: 11,120
Default

Both rears are plenty strong. The C clip is not something that goes easy. True, you would go for a ride if it broke and the axle came out from the rear. But thats not an everyday occurance. If it were, that rear would be extinct.
The only 2 rears I know of that do not have C lips are the Fords and Ma MoPars 8 3/4. It makes me wonder why there still not made today.
The 9 1/4 should be easy and cheap to obtain from the junk yard.
Reply With Quote
  #12  
Old 10-17-2002, 09:04 PM
caveman caveman is offline
Inactive User
 
Join Date: Jan 1999
Location: Penfield NY USA
Posts: 318
Default

I agree with that also,breaking c clips doesnt happen to much,if you were worried about it,I'm sure there is some heavy duty peices out there.That is a truck rear end,and I wouldnt worry about it much.You would be farther ahead to see if there was a 9" that would be close in width.You would just need the housing and a chuck,and reweld the perches on in the right spot,I cant imagine it costing more than 400-500 hundred bucks.Narrowing and posi unit,and gears,and custom axles in almost any other rear is going to be much more.Also I wouldnt sell the 8 1/4 short either,Your running a high stall converter,which takes a lot of the shock out of the driveline,that rear end would last along time I bet
Reply With Quote
  #13  
Old 10-17-2002, 10:13 PM
Dart Dart is offline
Inactive User
 
Join Date: Nov 1999
Location: Loveland, CO USA
Age: 54
Posts: 942
Default

Come on guys...a 9" Phord? Give me a break. I don't care how strong that silly rear end is I would NEVER put that PHORD piece of crap in a MOPAR.

I would suggest an 8 3/4. If you compare prices the silly PHORD costs near the same to build as a 8 3/4". It takes more power to spin the 9" and he won't be close to the breaking point on the 8 3/4. Stick with the Mopar rear.
Reply With Quote
  #14  
Old 10-17-2002, 10:48 PM
caveman caveman is offline
Inactive User
 
Join Date: Jan 1999
Location: Penfield NY USA
Posts: 318
Default

They arent crap.8 3/4 would be a good choice,either way would be OK,used stuff,save the high dollar crap for some one else
Reply With Quote
  #15  
Old 10-17-2002, 10:56 PM
Doug Wilson Doug Wilson is offline
Inactive User
 
Join Date: Aug 2001
Location: Sheridan, Oregon
Age: 79
Posts: 2,510
Default

When I mentioned the 9", I was only trying to make an example of relative strengths and costs. I would never advocate putting a crappy Ford rear end in any thorobred MOPAR vehicle.
Reply With Quote
  #16  
Old 10-17-2002, 10:59 PM
dave571's Avatar
dave571 dave571 is offline
Inactive User
 
Join Date: Feb 2001
Location: carstairs,alberta,canada
Posts: 2,809
Default

I'm a mopar guy, but the 9" ford is a great diff.

That's why all the custom guys use them. Cheap, easy to build, and strong. They seem to be commonly installed in virtually anything, chevy ford, dodge, rail jobs, whatever.

I go along with Doug's list posted earlier. Even if his sobriety is in question
Reply With Quote
  #17  
Old 10-17-2002, 11:12 PM
Doug Wilson Doug Wilson is offline
Inactive User
 
Join Date: Aug 2001
Location: Sheridan, Oregon
Age: 79
Posts: 2,510
Default

Virtually all street rod & custom car builders also use sb chebbies for power. I don't use chebbie engines, and I don't use furd rear ends.
Reply With Quote
  #18  
Old 10-17-2002, 11:22 PM
dave571's Avatar
dave571 dave571 is offline
Inactive User
 
Join Date: Feb 2001
Location: carstairs,alberta,canada
Posts: 2,809
Default

I wouldn't use a 9" either, I'm just saying they're not junk.

Funny thing is, I was thinking the same thing about custom guys using chevy engines when I made my last post.

Bow tie...Ick!!
Reply With Quote
  #19  
Old 10-17-2002, 11:23 PM
caveman caveman is offline
Inactive User
 
Join Date: Jan 1999
Location: Penfield NY USA
Posts: 318
Default

I would if the price was right.There's nothing wrong with a little engineering,Its a good strong choice,its probably stronger than a 8 3/4,and more parts availability.Believe me I'm Mopar through,and Through,but I have to disagree with that statement.I also think he should use what ever rear end that is closer to the width he needs.That makes the most sense,unless you just want to spend money
Reply With Quote
  #20  
Old 10-18-2002, 11:04 AM
KM KM is offline
Inactive User
 
Join Date: Mar 2000
Location: Helsinki,Finland
Posts: 772
Smile

Believe me I am too Mopar through and through....
If someone would give me a 9" or 429" or 12bolt or 454 I would never use them !
I would sell them to any idiot who wants them and use the money to buy Mopar stuff.

Good or not do not mix Mopar with ........

Kimmo
Reply With Quote
  #21  
Old 10-18-2002, 05:03 PM
caveman caveman is offline
Inactive User
 
Join Date: Jan 1999
Location: Penfield NY USA
Posts: 318
Default

You would go out and spend big bucks to have custom made rear end,$800-$1000 ,Thats not hotrodding,thats just spending money.
I have a bud who has Fords,and more that have chevies,I wouldnt call ant of them idiots.I have worked on all kinds of stuff from GTO's,Camaro's,Shelby's.I love my Mopars,but I'm not that stuck up about it.Like I say he should use what ever he can find that works,and be smart about it.Cubic money dont always cut it.You have to have some brains to go with it.
Reply With Quote
  #22  
Old 10-18-2002, 05:22 PM
Dart Dart is offline
Inactive User
 
Join Date: Nov 1999
Location: Loveland, CO USA
Age: 54
Posts: 942
Default

Speaking of brains Caveman, what you are saying is that if something is cheaper go ahead and use it? What kind of logic is that? Setting up a 9" in a car that didn't ever come equipped with it is silly. The 9" isn't that much cheaper, if at all, to build and the strength issue is still in the air besides that fact that the 9" uses up power because of it's configuration. Might as well use a 350 in a Dart beacause it is "cheaper" to build. Sounds like flawed logic to me...

You would know exactly what you have with n 8 3/4 and where exactly you need to move the spring perches etc. I am not saying throw your mony int he air, but why use the bigger hammer mentality. Just wait for an 8 3/4 that is appropriately priced and go from there. Most of the guys on this board price stuff real reasonably.
Reply With Quote
  #23  
Old 10-18-2002, 07:43 PM
caveman caveman is offline
Inactive User
 
Join Date: Jan 1999
Location: Penfield NY USA
Posts: 318
Default

I would use a 9",or a 8 3/4,what ever I could find reasonbably priced,A 8 3/4 didnt come stock with a Dakota either.As far as using up HP,I dont think you would ever notice the difference.I'm noy saying the 9" is better I'm just saying use what ever you can find at a good price.I wouldnt spend money on a Dana,or anything "big Bucks" like that.I'm sure what ever choice a 9' or a 8 3/4 would work just fine.As far as being that much of a purist I'm not.A little engineering and work and its done.No one can say the 9' isnt a stout unit,maybe a little stouter than a 8 3/4,you cant get much better for the money than a 9"with the ratio you want ,and a Detroit locker in it.The reason I sugested it was becuase I think one out of a early Mustang or Torino would be very close to what a Dakota would take in Width.Thats the method too my madness,plain and simple.I think a 8 3/4 out of a B body might be too wide (its worth checking),and a 8 3/4 out of a A body would take axles,and drums out of a B body car for the wheels too fit.The 9 has the same bolt pattern as the Dakota,and the B body.Personally this guy can do what he wants to at this point,and so can you.I was just giving my opinion.I surely woulnt wait for someone on this board to sell one,and ship it 1/2 across the country.I would go out and find 1 around my area.
Reply With Quote
  #24  
Old 10-18-2002, 08:22 PM
Cliff Foster Cliff Foster is offline
Inactive User
 
Join Date: Apr 2002
Location: Phnx, AZ
Age: 52
Posts: 426
wow

It's been suggested to me to find a 4X4 Durango with the limited slip allready in it because the rear is similar in width with my truck. I'm not sure if that is a 8-3/4 or a 9-1/4. But would that work in my application. I haven't yet ran the truck at the drag strip. I'm still waiting to get it back. I assume that it will be a little low on power because of the compression and not having the supercharger. But, the supercharger will be something that is coming pretty soon. It will be intercooled and running lots of boost. I can only guess that with some of the other 408ci stroker/blower combos that I've read on here that the HP will be in the neighborhood of about 500HP-600HP becuase I plan to run 12-14# when I race it. I may even have to change the tranny(44RE) out for something stronger. How hard is it to find a 8-3/4 junker or should I go with new? I'm going to dyno the truck here in about a week if I can get the 500mi breakin within that period of time.
Reply With Quote
  #25  
Old 10-18-2002, 08:31 PM
caveman caveman is offline
Inactive User
 
Join Date: Jan 1999
Location: Penfield NY USA
Posts: 318
Default

I'm not sure what a 4x4 durango would have,if its a 9 1/4 rear(it wont be a 8 3/4),that would be nice.Good luck finding one in a bone yard though(you may be able too).The 8 3/4 would be a good choice,measure your axle drum to drum,and look at the specs for 8 3/4 axles(drum to drum)see if any come close.These axles mainly came in mid to late 60's and very early 70's Mopars.So look for old mopars in the bone yard(dont rule out a 9" either).Many guys have older parts laying around,you just have to start asking around.You may come up with something all ready to be installed.You will have to remount the spring perches,and check your drive shaft length.But it is doable with out to much of a headache.
Reply With Quote
  #26  
Old 10-18-2002, 11:01 PM
The Dartman's Avatar
The Dartman The Dartman is offline
Inactive User
 
Join Date: May 1999
Location: Bettendorf, Iowa, USA
Age: 53
Posts: 579
Default

We all need to realize that Mopar did not/does not make every single part for a car better than any other car company. For example, how many powerglides are in the race cars here? I imagine quite a few, especially after witnessing at LEAST 50 Torqueflight transmission explosions at Monster Mopar last month.

If keeping a car all mopar is important, use an 8 3/4. If it's not, then there are other (better?) alternatives to be found. I mention that the Dana is argueably the strongest rearend, but even if the Ford and Mopar were the same price, I would (probably) chose the 9 inch since it has a removable center section. We're not talking about putting in a 10 bolt chevy grenade special...

Which brings up another point: There is a 11 second small black 70 Camero with an 8. 3/4 at my local track, as well as a Pro Street 10 second 69 Nova. I wonder if the Chevy boards give them crap about their rearends too?

Another point is that one of the best places to find a Dana with the hard to find 4.5 bolt circle is in mid 70's FORD trucks!!

Cliff - No ET information yet? What gives? This bad boy even been to the track yet?

Dartman

PS - Good to hear from "caveman" haven't heard from him in awhile. Not since the days of "Christopher" - where did he go by the way?

PS #2 - My first car (1986) was a 74 Ford Torino, 6 cylinder with a ford 9 inch. I think the width is pretty wide, but it should go into a truck and be the (I hope) correct bolt pattern. Been all mopar since then with a 73 Dart Sport, 69 Polara, 87 Charger, 92 dakota, 98 Stratus, and a 96 Dodge Conversion van.
Reply With Quote
  #27  
Old 10-18-2002, 11:36 PM
caveman caveman is offline
Inactive User
 
Join Date: Jan 1999
Location: Penfield NY USA
Posts: 318
Default

Hey Dartman,Its been awhile.I lurk around in mopar nascar some,Been having way too much fun this summer.I havent really posted much lately.I agree with what you said there by the way.Even GMs best the 12 bolt is lacking in any kind of strength,ask anybody that owns a BB chevelle,I bet they have twisted a few up,LOL.Like I said my point was to find something reasonably priced,and get it to work with out breaking the bank.I sure as hell wouldnt put a SB chevy in a Mopar as was suggested.
Reply With Quote
  #28  
Old 10-19-2002, 09:34 AM
Hammer 74's Avatar
Hammer 74 Hammer 74 is offline
Inactive User
 
Join Date: Feb 2001
Location: Arlington Hts, IL
Age: 56
Posts: 548
Default

I just finished putting a 9 1/4" in my Dart. Did not cost much to narrow and have axles made. Running a 3.92 gear and Auburn center. Works great.
Reply With Quote
  #29  
Old 10-19-2002, 10:38 AM
caveman caveman is offline
Inactive User
 
Join Date: Jan 1999
Location: Penfield NY USA
Posts: 318
Default

I think on a bang for the buck scale,the 9 1/4 is a great choice.They are strong easy to work on.You can even get 8 3/4 axle set up if you narrow it.Poor mans Dana so to speak,with out the weight and headaches of a Dana
Reply With Quote
  #30  
Old 10-19-2002, 07:59 PM
Cliff Foster Cliff Foster is offline
Inactive User
 
Join Date: Apr 2002
Location: Phnx, AZ
Age: 52
Posts: 426
Default

[Cliff - No ET information yet? What gives? This bad boy even been to the track yet?

Dartman

I've had a hell of a time just getting the damn thing back from the shop. When I first sent it in to be stroked they told me 3-4 weeks. That was July 4th. The first problem that I had was the magnum380 shortblock that I got from dodge had been decked so when I ordered my ROSS pistons they were too tall for the block and were hitting the heads(not good), of course we had to send them back to ROSS to be milled down(don't worry strength is maintained) and they took their time(3 weeks) to get the pistons back here to Az. Then the block had to be clearance for the rods. Got the engine back and ready to go and the block wasn't clearanced enough(.060 needed). Sent it back(10 more days). THEN had the motor put back together and the pushrods were hitting/rubbing my R/T heads. Had to have the passages opened up with a boring tool. Now that's done. While all along my mechanic can't really do outside stuff at work so he has to do it at home and it's getting darker here earlier now. He gets off at 5or6pm, but it's a few days away and I can't waite to do a little pavement ripping That's why no strip time, but you guys will be the first to know when she's ready. I'll also throw some dyno #'s in there.Keep in mind I have the stock rear with an open differential or whatever they come with.

But back to the rearend stuff. What about the rear for a Dakota R/T? Would that hold up or would I have to modify it as well? That might be a little easier to find.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Recommend a cam 78monoco Performance Talk 15 03-10-2007 02:58 PM
One reason why I recommend a PG to a TF Kevin Garceau Drag Racing Forum 35 02-08-2005 04:34 AM
Can somebody recommend a BB solid cam? RickyRick Performance Talk 10 04-24-2003 11:34 AM
Which hi-flo cat do you recommend? mybadodge Ram Truck Chat 26 12-31-2000 11:37 PM
what do you recommend? speedway Performance Talk 11 07-18-2000 10:06 AM




All times are GMT -4. The time now is 04:43 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
. . . . .