The 8 1/4 thread

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he got the carrier from you ?? and it was a 2.45 or down ring gear on it to begin with
 
No he wanted to use the high ratio gear for his car it is a brand new trac loc. His new 8 1/4 carrier is prob wrong for it. I thought he had the right carrier he did in 7 1/4
 
it seems as if you have a similar issue. the carrier ratio breaks are 2.45 and down (numerically) and 2.56 and up.

so if your 2.71s wont work with that posi carrier with your ring/pinon then it must be the 2.45 down unit and will never work for you if you want 2.56 and up ratio.
What gear set will work and fit in my 73 8 1/4 housing sir ??
No he wanted to use the high ratio gear for his car it is a brand new trac loc. His new 8 1/4 carrier is prob wrong for it. I thought he had the right carrier he did in 7 1/4
Never opened the 7 1/4 up, just the 8 1/4 like we talked about, the open carrier I took the gears off of and put them on the sure grip I got from you, we thought the sure grip was for the tall gears is what I was thinking... never talked about a 7 1/4 .. swaped to the 8 1/4.
 
I could be wrong but this is what im thinking is going on and what your options would be at this point.

2.45 and numerically lower uses one carrier because the pinion gear is so big the ring has to be moved further out. 2.56 and up uses another carrier because the pinion is smaller.

Its not a case of "will that carrier fit" because you have had it in there so you know it will fit and its just making sure you have the correct ring/pinion for the carrier you have.

Its hard because you dont know what gear ratio was on the carrier you dont know what it will accept and all mesh together and lne up and be able to adjust lashes.

but we have advantage knowing that the gear size break and 2.45 and down and 2.56 and up.

you have 271s and they wont work so you must have the carrier that works with 2.45s and down so yes( assuming all the rest of the info here is correct) you could put a different ring/pinion on that carrier and make it work BUT the biggest gear you could use is 245s
 
but again if you would be fine with a 245s (which is less gear than your current 271s but would be posi) i have the 245s that came out of my 74 8.25 and you could have them just pay the shipping. you would have to again get new bearings for the carrier and pinion but might be the lesser of two evils right now
 
Not with that higher carrier in the lower housing the higher housing the pinion is offset to the side and the lower housing is centered. So the higher carrier has to go into the "offset" housing and the lower in the "centered" housings, I think post #2 or so shows the difference. Need a good shot of his housing from the front or back to see which one he has. I have looked for numbers on them but no luck so far and of course I scrapped the old high housing I had a few weeks ago.
 
are you sure he has an offset housing or its just not a case of the pinion is smaller because of the wrong gear ratio on the wrong carrier ( carrier break issues) 2.45 and numerically lower uses one carrier because the pinion gear is so big the ring has to be moved further out. 2.56 and up uses another carrier because the pinion is smaller.

some folks make a spacer to put on there but im not sure how good running a spacer is like that long term but might be an option to use what he already has and solve the new bolt issue at the same time. So maybe search spacers for it and maybe even come in a kit with bolts seeing they will need to be longer to get through the spacer.
 
some more info i found

8.25 Tech Info

We change rear end gear ratios most often to change the performance characteristics of our cars - faster quarter mile times, or maybe even better gas mileage. But, what exactly changes inside the differential to make that happen?

Of course, changing the number of teeth on the ring & pinion gears will give you different ratios. Both pinion gears in the pic are for an 8.25 axle. The larger diameter gear is a 2.45, and the smaller diameter gear is a 3.21. The 3.21 gear set has a thicker ring gear and smaller pinion tooth count to archive that ratio. The 2.45 has a thinner ring gear and larger pinion tooth count. It is important to note that each of these gear sets must use a different carrier to achieve the change in ratio.

Sometimes manufactures use different carriers or cases to accommodate larger or smaller pinion gears, called a "case break". The mounting flange or surface that the ring gear rides on is located closer to the center of the differential for a smaller pinion like the 3.21, or it can be located outward for a larger pinion like the 2.45. Sometimes this can cause additional cost to a gear change, but can also gives you an opportunity to add a sure grip.

Two differential carriers were used in most 8.25 axles. Ratios smaller than 2.71 used one carrier and anything above 2.45 used a different carrier. Most consider the 2.71 and up carrier to be a “standard” 8.25 carrier, and the 2.45 / 2.26 to be a less desirable “special” carrier. Notice the carrier used with the 2.45 gear has the ring gear located about 3/8 inch further to the outside, away from the differential centerline, to accommodate the larger pinion gear. If the 2.45 gears had been designed for the standard differential, the ring gear would have been so thin that there would have been no room for the attaching bolts to thread into it.

It is possible to use a 2.71 or larger gear with the “special” carrier with the use of a ring gear spacer. This could lead to a reduced strength of the assembly. And, some tracks (at least used to) prohibit the use of spacers. It is not possible to use 2.26 or 2.45 gears with a standard carrier.
 
An Error Has Occurred!

Until today no one made the spacer for a 8.25 Chrysler rear end. After six months of modifying a Chevy ring gear spacer to use for the same swape with 3:90 gears in my own 73 Charger I decided to make the spacers.
If at least 30 people need them for 60$ each. Summit has arp .990 bolts for around 33$ so you get back 1/16" of thread lost top the spacer with stock bolts. I can be contacted at {[email protected]}
 
Good link on the info, hard to explain myself in that way. Just got off the phone with Mike and is hooked up know with your 2.45 and my install hardware. There was a guy a few months ago that wanted a spacer. Great idea, put it in the for sale section. The high gear track lock carriers are usually under 100 new, and it seems to be quite a few out there.
 
ya i will get him set up with my gears.

has he seen and know that there is a spacer option that will allow him use what he has a run the bigger gear
 
He has the offset housing, but it would work in the centered housing. I am book marking that since I get as many 8 1/4 as I can find and re build them.
 
Never understood why people do not like them they stand up pretty well on the street.
 
Mike do me a favor and write all the casting numbers of that carrier down I will start a list so people don't get messed up.
 
Thank you two for all the time,Help and info that I have learned here.
I can't say it enough but this has been a head banging thing to deal with..
You two members have sure stepped up and helped this old guy on the hill this morning.. :thumbsup::thumbsup:
 
Next time mine is up I will grab them also. Wonder how many different ones are out there? Two bad I just scrapped two of them that I cut the flanges off for the disk brake mockups.
 
Thank you two for all the time,Help and info that I have learned here.
I can't say it enough but this has been a head banging thing to deal with..
You two members have sure stepped up and helped this old guy on the hill this morning.. :thumbsup::thumbsup:

That just because you are special Meme!
 
Thank you two for all the time,Help and info that I have learned here.
I can't say it enough but this has been a head banging thing to deal with..
You two members have sure stepped up and helped this old guy on the hill this morning.. :thumbsup::thumbsup:


so very welcome glad to help.i just pulled the ring gear and here are a few pics.
r1.jpg
r2.jpg
r3.jpg
r4.jpg
 
Seeing those always makes me laugh the size of the pinion gear.
 
You men just help the man on the hill get a good nights sleep tonight !
I am indebted to you two men, I am so glad you guys read my posts and jump in to help members like you do..
 
all good buddy thats what we are here for and you would ( and have done) the same for others
 
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