How do I switch an 8.25 Small Bolt to a Big Bolt pattern?

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360-68cudu

360-68cudu

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So I wanted to switch over to a Big bolt patter. and what is the cheap and reliable way to do so?
 
all 8 1/4 rear ends are 5 on 4 1/2 from the factory. so either you dont have an 8 1/4 , or someone somehow put small bolt pattern axles in it, or redrilled them for a 4" pattern, in which case, most SBP wheels wont fit the hub even if they are re-drilled.
 

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You're Right 73AbodEE!! :) I was mistaken I have 68 Barracuda with a 8 3/4 with a small bolt pattern I wanted to see what way I could switch it to a big bolt
 
360-68cudu said:
You're Right 73AbodEE!! :) I was mistaken I have 68 Barracuda with a 8 3/4 with a small bolt pattern I wanted to see what way I could switch it to a big bolt
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you have a few options. you could get new axles from dr. diff or similar good company. i have read a number of threads where folks have had them re-drilled professionally, and they went on to live a long happy life even down the 1/4 mile. i have used billet aluminum wheel adapters for years with great success, but then you are sacrificing backspace. if you have the money and resources, i would get new axles. my $0.02
 
Or You Could Go With Adapters. I Have A 8 3/4 Rear With Small Bolt Pattern Axles And Im Using Adapters To Go To The Bigger Bolt Pattern.
Thats The Cheapest Way. Or You Can Swap The Axles.
But The Adapters Allow For More Clearance Between The Tires And Your Springs.
 
Beware of adapters in cases where the welded weights on the drrum interfear with the adapter as suggested in the picture above. The adapter must sit flat or it will work loose.
To grind clearance in the adapter or grind away some of the weights is often required.
Adapters got a bad reputation years ago because they weren't properly installed.
 
RedFish said:
Beware of adapters in cases where the welded weights on the drrum interfear with the adapter as suggested in the picture above. The adapter must sit flat or it will work loose.
To grind clearance in the adapter or grind away some of the weights is often required.
Adapters got a bad reputation years ago because they weren't properly installed.
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i had a pair of those cast aluminum trans dapt adapters. those things cracked on me in the first month i had them on and they were perfectly flat on the hub... total junk IMO. the billet aluminum adapters are the only way to go if one must use them.
 

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RedFish said:
Beware of adapters in cases where the welded weights on the drrum interfear with the adapter as suggested in the picture above. The adapter must sit flat or it will work loose.
To grind clearance in the adapter or grind away some of the weights is often required.
Adapters got a bad reputation years ago because they weren't properly installed.
Click to expand...



X2^ I Had To Grind The One On The Right Rear To Lay Flat Left Side Was Good.
 
73AbodEE said:
i had a pair of those cast aluminum trans dapt adapters. those things cracked on me in the first month i had them on and they were perfectly flat on the hub... total junk IMO. the billet aluminum adapters are the only way to go if one must use them.
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Im Curious Did They Crack From Defects Or From Being Over Tourqed?
:blob:
 
71DodgeDemon340 said:
Im Curious Did They Crack From Defects Or From Being Over Tourqed?
:blob:
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they cracked because they are cast aluminum and very brittle. if the hub face is even remotely imperfect , they will eventually crack. when i returned them , i was told that they get a lot of them back and they instantly gave me my money back. they were torqued to 80 lbs, exactly what was on the sheet. i went and bought some 1" thick ,billet adapters , 4" to 4 1/2 off ebay for 69.00 a pair shipped. i ran those for over 2 years on the front and back. i trust those with my life. the billet aluminum is much stronger and wont crack. im not trying to worry you, just sharing my adapter experience. ive ran a lot of these over the years, and the cast aluminums should be discontinued in my opinion
 

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71DodgeDemon340 said:
Im Curious Did They Crack From Defects Or From Being Over Tourqed?
:blob:
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I have a set of transdapt adapters on my Barracuda and ran the living crap out of them with plenty of burn outs and they never cracked. I think some were good and some were trash so do you want to chance what ones you might end up with? I buy all of them I can pick up cheap no matter what they fit because I keep them to use on my rollback wrecker so I can take a set of wheels and adapt them to about any car. Sometimes I have a couple adapters to a wheel but they are just so I don't damage the car in loading.

Truely you want the billet adapter like 73AbodEE is showing you.
 
Not to get of topic but im curious because i got these ones with the car when i bought it, theres no brand on them but they say SEMA approved idk.

:happy1:
 
71DodgeDemon340 said:
Not to get of topic but im curious because i got these ones with the car when i bought it, theres no brand on them but they say SEMA approved idk.

:happy1:
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yes , all the trans dapt adapters says "sema" on them. i felt good about them at first. coincidently, i painted them black when i put them on. a month later , i took my wheels off to check them, low and behold my passenger side front had a decent sized crack that i could see because of the black paint. this is normal everyday driving, no huge bumps or potholes. prior to putting them on, i had taken the drums off and scuffed them real good , so i know the surface was a perfect as it could get. as Okla says, some are good , some arent. i also know another guy that ran them with no problems, but im sure some slip out that are defective.
 
So if I change my axels essentially what I’m doing is going from 5 on 4" bolt pattern to larger 5 on 4-1/2" pattern. This will open up a wider selection of wheels to me, correct? Can any one estimate how much it will cost to machine my drum Brakes and how much it will cost to convert to disc brakes in the back? I already have the front disc brakes. Also the 4" and the 4-1/2" is the technical measurement from where to where on the wheel?
 
360-68cudu said:
You're Right 73AbodEE!! :) I was mistaken I have 68 Barracuda with a 8 3/4 with a small bolt pattern I wanted to see what way I could switch it to a big bolt
Click to expand...



Do it the right way and be done with it..

Buy large bolt pattern axles And use large bolt pattern brakes too. Easier to get brake parts for that way, plus you will know how and what fits..
 
73AbodEE said:
yes , all the trans dapt adapters says "sema" on them. i felt good about them at first. coincidently, i painted them black when i put them on. a month later , i took my wheels off to check them, low and behold my passenger side front had a decent sized crack that i could see because of the black paint. this is normal everyday driving, no huge bumps or potholes. prior to putting them on, i had taken the drums off and scuffed them real good , so i know the surface was a perfect as it could get. as Okla says, some are good , some arent. i also know another guy that ran them with no problems, but im sure some slip out that are defective.
Click to expand...

Those Billet Adapters Look Good But The Problem Is The Ones I Got Now Are Only Like A Half Inch Thick And The Only Billet Ones I Can Find Are 1 Inch or Bigger.

The One Inch will Put My Tires To Far Out, I Think Im Gonna Run The Adapters I Got And Just Check Them Periodically.
 
360-68cudu said:
Also the 4" and the 4-1/2" is the technical measurement from where to where on the wheel?
Click to expand...

see post #2

71DodgeDemon340 said:
Those Billet Adapters Look Good But The Problem Is The Ones I Got Now Are Only Like A Half Inch Thick And The Only Billet Ones I Can Find Are 1 Inch or Bigger.

The One Inch will Put My Tires To Far Out, I Think Im Gonna Run The Adapters I Got And Just Check Them Periodically.
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those adapters you have are 1" thick.
 
You can get them re drilled for $65. at Moser Engineering. a lot safer than wheel adapters.
 
Been down this road with a customers 71 duster that came in with sbp axles that were converted to bbp. The drums used were bbp that don't work with sbp alxes. I machined new sbp drums on my mill for bbp and the 10 x 1 3/4 brakes and everything was good. We have since changed the car to moser bbp axles and 10 x 2 1/2 bbp drums for better stopping power. I sold the drums some time ago but still have the axles if you are interested but my advise would be to get bbp axles and drums from the start along with the bigger brakes. The cost of machine work and labor to change over will not save you much. Do it right and be done with it.
 
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