Welded 7.25

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InItSwingIt

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Anybody ever weld up the spiders on a 7.25 cus thier a chepo like me... whatd you put it behind, how hard you drive it, and how long did it last, and what breaks next... thanks in advance...
 
I have done it for mud in a demo derby the next weak spot is the shafts.
Kinda what i thought... less it was a bearing or sum... how much abuse did ot take before it went... i take it you abused it pretty good behind a 318 or 360?...
 
So i can just assume itll be fine for driving around town and doing burnouts? Untill it decides it isint ok anymore and snaps an axle... yea?
 
So i can just assume itll be fine for driving around town and doing burnouts? Untill it decides it isint ok anymore and snaps an axle... yea?
What is going to make it break a shaft is on turns both shafts do not turn the same speed. Slow on turns and it may make a few burnouts. lol
 
Ok, who did what here?
I posted this in the "heater smokes up the interior" thread.:D

Sure you did Beast.... Sure you did....
Now go take a short nap and everything will be ok when you wake up.

Getting old is tuff.... Lol
 
What is going to make it break a shaft is on turns both shafts do not turn the same speed. Slow on turns and it may make a few burnouts. lol
If i weld it theyll go the same speed, which is the prob... lol... i get what ur sayin tho... straight line burn outs and try and stay out of it around hard turns...
 
Sure you did Beast.... Sure you did....
Now go take a short nap and everything will be ok when you wake up.

Getting old is tuff.... Lol

Ok, so I went and took a nap and it didn't help. :D
Something got crossed with another thread somewhere, and I'm not EVEN going to try and figure out where.
I even have proof.:D


Untitled.jpg
 
Hahah... well... now that ypu had a nap, and since your here, how long you think an welded 7.25 will last?...

It's hard to say really, since the wear on it already and how much grip the roads average, along with how many tight turns on those roads are done.
Personally, even though I almost did it myself I think it's kind of a once done it's on it's way to being over.
You just never know when.:D
 
I broke a 3.55 7 1/4 SG behind a 340 in my '65. The pinion took a chunk out of the ring gear and the pinion then turned into a barrel. Now it may have ingested a piece of broken spider gear or something but it was a stinky mess in there. That was on 10" wide tires so there was some 'stress' on this rear end. Replaced it over the weekend with a Junk yard 2.76 one legger so I could get to school and that car was never the same.
 
I think it's kind of a once done it's on it's way to being over.

I feel it... your kind of sign its death warrent from the start....on the other hand, people practically give em away, even if i go thru a couple it probly wont cost me close to anything... itll probly give out if i ever get that 360 in there though...
 
7 1/4 are practically falling out of the trees, so if you don't mind the labor...
 
I think it's kind of a once done it's on it's way to being over.

I feel it... your kind of sign its death warrent from the start....on the other hand, people practically give em away, even if i go thru a couple it probly wont cost me close to anything... itll probly give out if i ever get that 360 in there though...

I don't know as I have layed into mine pretty hard with a mild built 5.9 Magnum, but it's always been just throttle and no harsh shocks on it.
When I was considering it was because I am going to put an 8.25 anyway, but then I realized the Wife's 72 is going to be needing the large bolt pattern, so I decided to spare it the certain death.
 
You might keep in mind that breaking a **** rear end can ruin the sprag in the automatic, "if that's what you have."

Actually, "in the old days" a friend of mine broke the 10 bolt in his 65 Chevelle, and after we got the axle replaced, we discovered THE MUNCIE 4 SPEED INPUT SHAFT HAD SNAPPED

This is the guy who later was the first owner of my 70 440-6 RR. When I arrived at Navy Electronics "A" school at Treasure Island in the fall of 68, and eventually made my way to the then fantastic amateur radio club, K6NCG,

(Some photos of the club here:)

K6NCG - Treasure Island Radio Amateur Club 1969-1970

here sits George's 65 Chevelle. "It turns out" that he had bought and junked out a low miles wrecked 67 350, 4 speed Camaro. So now the 350/ 4 speed and Rally wheels were on the Chevelle

"Sometime later" after we had become friends, he was (as usual) building up the muscles in his right (throttle) foot, his left (clutch) foot, and his "shifting arm" ..........getting onto the San Francisco Bay Bridge leaving "the Island" and broke the rear axle going into second gear off the on ramp.

We coasted for awhile, "dived" into a turnout on the bridge just as the rear end locked up. There were 3 or 4 of us in the car, I don't remember. Two of use jacked up the car and got one rear wheel setting on the spare tire. I crawled under and removed the rear cover. The C clips fell out as we tried to gut the thing and get it to turn, and neither of us!!! knew what the C clips were for!!!

So here comes the tow truck, who decides to PUSH US down off the bridge. As we went down the ramp, an horrible rubbing of the tires insued!!!! Of course there ARE NO BRAKES because this is before dual master cylinders!!!

But George is a pretty smart guy, and already had a "line lock" on the car. He pushed the button, and "stabbed" the brakes a couple of times to build a bit of pressure in the fronts..........and we rolled to a gentle stop at the bottom of the bridge!!!

Tow truck went around, hoisted the rear, and towed us all back to the island!!! LMAFAO!!!!

We bought a used 10 bolt at a junk yard, and put the thing in. Started 'er up and IT WENT NOWHERE!!!

NOTICE this photo of a Muncie shaft I found on the www

6-input-shaft.jpg


NOTICE the groove around the shaft splines........I know not what they are for, but that shaft BROKE RIGHT THERE in that groove just as clean as could be, and !!!POOF!!! we have a 'free' alignment tool for putting the clutch in!!!
 
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You might keep in mind that breaking a **** rear end can ruin the sprag in the automatic, "if that's what you have."

Actually, "in the old days" a friend of mine broke the 10 bolt in his 65 Chevelle, and after we got the axle replaced, we discovered THE MUNCIE 4 SPEED INPUT SHAFT HAD SNAPPED

This is the guy who later was the first owner of my 70 440-6 RR. When I arrived at Navy Electronics "A" school at Treasure Island in the fall of 68, and eventually made my way to the then fantastic amateur radio club, K6NCG,

(Some photos of the club here:)

K6NCG - Treasure Island Radio Amateur Club 1969-1970

here sits George's 65 Chevelle. "It turns out" that he had bought and junked out a low miles wrecked 67 350, 4 speed Camaro. So now the 350/ 4 speed and Rally wheels were on the Chevelle

"Sometime later" after we had become friends, he was (as usual) building up the muscles in his right (throttle) foot, his left (clutch) foot, and his "shifting arm" ..........getting onto the San Francisco Bay Bridge leaving "the Island" and broke the rear axle going into second gear off the on ramp.

We coasted for awhile, "dived" into a turnout on the bridge just as the rear end locked up. There were 3 or 4 of us in the car, I don't remember. Two of use jacked up the car and got one rear wheel setting on the spare tire. I crawled under and removed the rear cover. The C clips fell out as we tried to gut the thing and get it to turn, and neither of us!!! knew what the C clips were for!!!

So here comes the tow truck, who decides to PUSH US down off the bridge. As we went down the ramp, an horrible rubbing of the tires insued!!!! Of course there ARE NO BRAKES because this is before dual master cylinders!!!

But George is a pretty smart guy, and already had a "line lock" on the car. He pushed the button, and "stabbed" the brakes a couple of times to build a bit of pressure in the fronts..........and we rolled to a gentle stop at the bottom of the bridge!!!

Tow truck went around, hoisted the rear, and towed us all back to the island!!! LMAFAO!!!!

We bought a used 10 bolt at a junk yard, and put the thing in. Started 'er up and IT WENT NOWHERE!!!

NOTICE this photo of a Muncie shaft I found on the www

View attachment 1715126138

NOTICE the groove around the shaft splines........I know not what they are for, but that shaft BROKE RIGHT THERE in that groove just as clean as could be, and !!!POOF!!! we have a 'free' alignment tool for putting the clutch in!!!
Hahhah... the c clip thing got me. I had not thought about the sprag. Its just a 904. If i recall, bad sprags can lead to exploding torqflight syndrome... but a 7.25 on tired old springs shouldent be too dramatic if it snaps an axel... it wont do the chevy "pull out" thing if it snaps will it? (Like with C clips, lol).... my wheels not falling off or anything crazy?
 
Have you noticed that nobody likes this idea? Get some money together and do it right.
 
Hahhah... the c clip thing got me. I had not thought about the sprag. Its just a 904. If i recall, bad sprags can lead to exploding torqflight syndrome... but a 7.25 on tired old springs shouldent be too dramatic if it snaps an axel... it wont do the chevy "pull out" thing if it snaps will it? (Like with C clips, lol).... my wheels not falling off or anything crazy?
Yes when an axle shaft snaps it comes out on its own with a 7 1/4
 
Yup. ANY C clip axle. You either break an axle or break something that "removes" the clip it will come right out.
 
Yup. ANY C clip axle. You either break an axle or break something that "removes" the clip it will come right out.
I never opend up a 7.25 before... i didint realized it was a C clip deal... that kinda blows... i might still do it anyways...
 
7.25s are NOT C clip rears...and welding one up will increase its strength tremendously.
Moderate weight car...less than 3500 wet, less than 300 horsepower and auto trans, it should last a good, long time.
 
7.25s are NOT C clip rears...and welding one up will increase its strength tremendously.
Moderate weight car...less than 3500 wet, less than 300 horsepower and auto trans, it should last a good, long time.

I agree with the first, but not necessarily the last. I know a couple guys who broke them with 318s. Just depends on "how big" your foot is LOL

Since this is winter, when I was really young, long about the winter of 67-68---I drove a 57 Chev clear through winter with "weld-a-lock." "It was interesting."

Just the other day I had fun kicking the (limited slip) Dakota around a corner in 2 WD. The local PD would have not been impressed LOL
 
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