8 1/4 rearend

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moparmaddnes

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On my demon there is an 8 1/4 rear from 69 b-body which I got from the part #. It fits in nice I looked to see if it was narrowed down but could't see any evidence. My ? is how strong is this rear and is it hard to get parts for? I wan't 3.55 or 3.91 for gearing and have 340 that I will be rebuilding with projected hp of around 350 t0 450. Any and all advice will surelly be appreciated.
Thanks Matt
 
easy to get parts for...one thing to watch out for is if its a 2.45 ratio you will need a different carrier to go to the gear ratios you want...I run 8 1/4" in my 75 340 duster, 400hp and no problems, but im not out torturing it either...if your draging id probably recommend going to an 8 3/4" or Dana
 
This may be a silly question but here goes!! , can you put a sure grip in to the stock 8.25 rear end? We have a 73 Duster with the /225 in it now but we are putting the 360-400hp engine in soon,so if this is possible this is way for you to go too.with a sure grip.

Bob
 
MR.7DUSTER3 said:
This may be a silly question but here goes!! , can you put a sure grip in to the stock 8.25 rear end? We have a 73 Duster with the /225 in it now but we are putting the 360-400hp engine in soon,so if this is possible this is way for you to go too.with a sure grip.

Bob

Of course! Sure grips for the 8 1/4 are readily available.
 
yea mine has mine has a moparperformanace 355 suregrip gearset but u can get other brands good source is summit
 
Hey guys, I found this sure grip on Summit Racing today, its a Mopar Performance part # DCC-4529273 for $309.95,says it's a clutch style limited slip ,10 cover bolt ,27 spline designed for gear ratios of 2.76:1 Would this be something that we would be able to bolt right in to our 8.25 rear end ? We replaced the axles once on the Duster and that wasnt too hard to do .What else do you have to repl in there?

Dont mean to sound stupid but the only thing stupid is if I didnt ask and just went and bought this thing.

thanks,Bob
 
About how much will rebuilding this rear cost and does it then become a stronger rear, since there are new and better parts with better materials. I also have 8 3/4 from a B-body, but would need to be shortened. Would this be a cheaper and better way to go?
 
I have an 8 1/4 sure grip I will sell for $125.00 plus shipping... :thumbup:
 
101_1706.jpg
 
MR.7DUSTER3 said:
Hey guys, I found this sure grip on Summit Racing today, its a Mopar Performance part # DCC-4529273 for $309.95,says it's a clutch style limited slip ,10 cover bolt ,27 spline designed for gear ratios of 2.76:1 Would this be something that we would be able to bolt right in to our 8.25 rear end ? We replaced the axles once on the Duster and that wasnt too hard to do .What else do you have to repl in there?

Dont mean to sound stupid but the only thing stupid is if I didnt ask and just went and bought this thing.

thanks,Bob
I dont know that you can put clutch type suregrips in an 8 1/4.
 
I just bought a 3:73 ring and pinion 58.00 and a posi in the carrier with bearing 80.00 on ebay. I am doing the same switch as you. i pulled and 8.25 out of a 74 dart, springs and all in one piece and am going to have it professionally set up as I know nothing of setting a ring and pinion. It will go in my 73 duster. Walt :nike:
 
This one's still available if anybody wants to come pick it up:
http://www.forabodiesonly.com/mopar/showthread.php?t=10132
It's 5x4.5 2.76 open F-body, about 2 in. wider than stock A-body. Worked fine in my Duster with 255 60's, but clearance was tight. Kinda like using a Bbody rear, 'cept the perches are correct 43" Abody width.

FREE!!! Get it out of my garage, PLEASE!!!
 
Well, having a choice I'd go for the clutch type. I say that because the 8 3/4 uses the clutch type. Also they rebuild easy, the clutch that is.
 
I still would like to know if rebuilding the rear with new parts would the rear be able to handle more power? My thoughts are yes, but don't know. And at the price of rebuilding it would it be cheaper to get 8 3/4 instead? :wav:
 
I dont think rebuilding the rear would make it stronger, possibly putting lower gears in would make it stronger(higher number, 3.55, 4.11)but not sure how that works. Are you going to set up the gears yourself? Call around and get prices if you're not doing it yourself. Have you considered a ford 8.8? That is the route I took, 8 3/4 are expensive up here, IF you can find one.
 
If your going to replace the open unit with the SG unit only, you can probably do it yourself with a little mechanical knowledge. Main thing you'll need is a dial indicator to find out what your gear backlash is before you take it apart so you can set up the same when you put it together. if your changing gears too thats a whole lot harder, you may want to let a knowledgable tech do it for you.
 
Any B- body rear will fit in a a-body if you pry the springs together. The right way to do it right is to move the perches together 1 inch. It's 1 inch wider so watch the wheel offset.
 
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