Who's a good positraction builder.
Are there any good Positration differential shops in Nashville TN or Evansville, Indiana.
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Re: Positration differential in Nashville or Evansville, Indiana
Chester
If you don't get an answer here check out your local car shows and cruise ins. Talk to some of the older hot rodders. -
Who's a good positraction builder.
No one in home town can do it so can anybody recommend a good differential builder for a 1964 corvette. I found Bair's corvette through the search but are there any others, thanks.Comment
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Re: Who's a good positraction builder.
Chester,
this 4 pages long thread with copious photos ran for weeks on this forum.
It illustrated the meticulous work of fellow club member Gary Ramadei does on corvette differentials.
https://www.forums.ncrs.org/showthre...300-000-miles-!Comment
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Re: Who's a good positraction builder.
Chester -
Do you know if your '64 still has the original Dana posi unit? Most have been updated to the Eaton unit, as the weaker original Dana units had durability issues and there are no parts available to rebuild them any more.Comment
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Re: Who's a good positraction builder.
Suggest Ikerds in Bedford, Indiana. Been in business for MANY years with an excellent reputation. Advertises in the Driveline.
Gary Ramadei in Connecticut is also an excellent rebuilder. It just requires more effort and $$ to get the differential to/from him. But many folks do it this way. He is my first choice.
LarryComment
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Re: Who's a good positraction builder.
Chester,
I would highly recommend Gary Ramadei. Costs more but certainly worth it. He meticulously rebuilds it and you will never have another problem with it. Best $ I spent on my 63.
TimComment
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Re: Who's a good positraction builder.
Have not pull unit yet but we know the history of the car and I'm 90% sure the unit has never been apart. I've talked to 3 well know shops and prices are anywhere from 1400.00 to 1700.00. That's assuming the unit can not be rebuilt as 63/64 parts are no longer available and they would have to install a newer unit. I want to use the existing case as it has all the correct numbers. Have not talked to Gary Ramadei in Connecticut yet but conn is really to far away.Comment
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Re: Who's a good positraction builder.
Hi guys,
I was referred to this thread this evening by a fellow member. First I would like to thank those here that have mentioned me, some of whom I have already built diff's for. This is not a solicitation for my work, I am booked up into the Fall right now.
What I can do is offer some advice on what you may have to look forward to. If you are planning on attending Carlisle next month I will be hosting another open forum on vette diff's, including posi building, boxes and trailing arms. This may help you. I can also post or send you links to differential overhaul threads I wrote over the years. I have coached guys from around the world , including Australia, New Zealand, Japan, and South Africa on building a better diff then what you may find locally or online. I continue to get them in that were "rebuilt" before.
So if you have a true 1964 vette posi differential then you have some areas to check. First off, if you are NOT interested in numbers but just want a dependable, strong differential then you might not want to rebuild this one. If you want to rebuild this to keep it with the car then most of it will need to be replaced. Here is why:
63-64 posi's were Dana's as John mentioned. They were a poor design, with external long compression springs. For the engines used in the 63 lineup they were ok. For those who pushed their car hard and later on popped a BB in there to go racing often found the diff locked up from a cracked posi case or sheared pinion. Sometimes they just broke without a lot of abuse. Yes there are still originals out there, I still get them in but many were replaced with Eaton posi's by the mid 60's and beyond. In '65 the Eaton posi was used BUT these also had issues in what I call the first design. The posi casting was the issue and led to cracking, which is a time bomb for locking up. That link to Jack Panzica's diff build is a good example of a cracked posi locking up and splitting in half. That was the first time I could not get the posi out, it imploded and wedged into the housing. I had to burn it out and ended up tossing all of it, less the pinion yoke and axles, in the recycle barrel. The spiders used in the 65-70 are not as strong as the later 71- 79's. 71-79 diff's have better housings and cases and are a good alternative if you decide not to build the 64.
The other weak area in 63-64's were the pinion gears since they had a sharp corner by the small crush sleeve. At this point they snapped and locked up the diff. This design was used into '65 and should not be reused. The spline count was coarse 17 like the axles. The splines changed by mid '65 to the current design and the pinion was also changed to a tapered length with longer crush sleeve. This solved this issue but the weaker posi's ran into 71. Those later diff's had other issue too, like soft faced axles, weak clutches, and ring gear bolts that changed from a good design to a poor one. The 80-82 are the worse of the lot but those are not a consideration.
I don't know what your plans are. If you expect to find a rebuilder to rebuild that Dana - good luck. The common rebuilds on the market today, from typical locals to vendors, are stock type builds. Those are ok but I would never use or build one. I like to address the issues to build a better unit. Built to application these can hold up very well. The most power in front of one of mine was just over 950hp at the flywheel. That not a stock vette 10 bolt but rather a 1480 12 bolt IRS. My son's 75 has 550 at the wheels and pulls the front end off the ground, it too sports a 12 bolt IRS. So if you can detail what your plans are I would be glad to offer advice. For posi's - I never build them with the springs or plates, something most will tell you won't work but I beg to differ. The posi should first be blended, polished then tuned for the best performance and life. Most of that is detailed in Jack's thread. You can also see it on YouTube just look up Tom's eaton posi tuning.Comment
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Re: Who's a good positraction builder.
Thanks for your long thread. I know it took time to write so I appreciate it. I want to at least keep the housing as it has the correct numbers and dates. Not concern with the inner parts and their dates. This car will never be run hard. I just want a good driving dependable car. Since you are book up till fall I will not bother you as I would like to get the unit sooner. If I'm reading you right, I should not even think about having my unit rebuilt because of the weakness. I should just concentrate on finding someone who can install a newer unit in my casing. I'm thinking about Bair's corvette. If not them can you recommend someone close to Western KY. There is a garage in my town that works on modern differentails and he said he could rebuild but he's never done one. With engines, most anybody can rebuild those including myself, but not sure how much talent you need to rebuild rearends. Since these are a pain in the a&& to take out and put back in, I want it right with no problems. Sure do not want to remove twice. thanks chetComment
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Re: Who's a good positraction builder.
You're welcome. I do this all the time. Yes I have several HP builds in line now. Brian Bair is a good guy and will be able to help you. While I don't believe they polish and tune a posi you could ask them. For a driver it isn't required it's just the way I do them.
I would not attempt to rebuild that Dana, nor would I use a new loaded Eaton with fiber clutches and huge springs. You do not want to use anything but solid steels for clutches- stay away from the fiber coated ones. The cases were discussed already but you are going to need new spiders as well. I don't like the ones in the new loaded cases either and don't use them. A good set of used 10-17's or new ones are what you want. I would use a NOS Eaton case made for Chevy over the aftermarket loaded Eaton. The castings of the NOS cases are better.
I don't think you are going to find a place that builds them like I do, maybe but I'd be surprised. However, if your local guy is good at differentials he should have the tools and knowledge to do a stock type build so that might be an option. The basic theory is the same, setting up the pattern is not unique to the vette just the RG size is.
Now if use a guy or do it yourself then you're going to want to know what parts to use. Not all the master kits are the same out there. Some will have non Timken bearings, do not use these - stay with USA Timkens. Some use cheap seals, again beware. The side shims used in the 63-66 diff's are obsolete. Joe Lucia might know of similar sizes used for new trucks or cars. I still have stock of them that I grind to size. The shims in the kits are set up for the later 67-79 housings and will not work. Also use ARP RING GEAR bolts over the kit bolts or reusing the old ones. The ARP are the best and worth the extra money. Check the fitment of the bearing caps to the new races and keep the caps to the correct sides. Replace the original 5 line hex bolts in the caps with stronger socket heads and torque to 60 ft/lb. The cap fitment should be 001 rock, not more or less.
If you can build an engine and do the measurements with real tools you probably can build a diff but that is something only you can decide on.Comment
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Re: Who's a good positraction builder.
Chester,
My recommendation (what I would do) - get in line with Gary R. and make it a fall project.
TimComment
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