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Small block 521


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I'm beginning to really see the previous problems with the gears breaking being seriously attributed to the pinion angle

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This photo I'm not even holding my phone perfectly square but it's just jumps out at you how angled it is.

Really appreciate all the input because I just had no idea about these things. Ratsun is the shit.

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Keep in mind a few things

You can obtain a 3" drop with a pretty good load of lumber, with out having to add degree of pinion.

Blocks with degree added start at 4" and up. Even if your pinion is way off, say like a lifted 70's 4x4 chevy, with a super short front shaft, the angle is to great for the u joint not to bottom out, but if you get to that point, it would jack up the u joint way before the ring and gear, so if your u joint is not being forced to do more angle of deflection than designed, it would never damage ring gear. That has to do more with it being old as dirt. A 3" flat block would not attribute to that damage. Don't get me wrong, correct or perfect pinion angle is important, but it becomes that more when circle track racing with high hp with hard

Exceleration, to pull out of the turn and hook up, and hard braking.

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Keep in mind a few things

You can obtain a 3" drop with a pretty good load of lumber, with out having to add degree of pinion.

Blocks with degree added start at 4" and up. Even if your pinion is way off, say like a lifted 70's 4x4 chevy, with a super short front shaft, the angle is to great for the u joint not to bottom out, but if you get to that point, it would jack up the u joint way before the ring and gear, so if your u joint is not being forced to do more angle of deflection than designed, it would never damage ring gear. That has to do more with it being old as dirt. A 3" flat block would not attribute to that damage. Don't get me wrong, correct or perfect pinion angle is important, but it becomes that more when circle track racing with high hp with hard

Exceleration, to pull out of the turn and hook up, and hard braking.

I hear what you're saying I have a coworker with a daily driven ram charger that's pretty high up and he's thrown three driveshafts but never damaged ring gear, transmission, or transfer case. Pinion angle is super foreign to me. I'm just gonna have to see how it goes and if the driveshaft starts humming or acting funny then I'll prollly change the angle, but then by that time I might even have the new beefy rear diff
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You and I are kinda sim. with both running V8's

I was running about 250 HP 1st time around.

Not sure what your running in your Generous Motors,

But if you run a stock 521 gear, it's gonna be way too low, you can buy some time, but save your self some grief and get yourself a 9" ford, they are all over the place cheap to narrow and plenty strong, with great gear selection.

I'm running 3:90 gears, and was turning 2100 rpm

At 70 mph with a 4 speed auto. not sure what your final ratio is in your Trans.

Also don't put slicks on it, cus your reared will only give you 1/2 a run if get my drift.

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You and I are kinda sim. with both running V8's

I was running about 250 HP 1st time around.

Not sure what your running in your Generous Motors,

But if you run a stock 521 gear, it's gonna be way too low, you can buy some time, but save your self some grief and get yourself a 9" ford, they are all over the place cheap to narrow and plenty strong, with great gear selection.

I'm running 3:90 gears, and was turning 2100 rpm

At 70 mph with a 4 speed auto. not sure what your final ratio is in your Trans.

Also don't put slicks on it, cus your reared will only give you 1/2 a run if get my drift.

 

 

Im running 400 + hp , and I'm running a stock datsun rear end with 295/50/15's , And I have been for years without any problems at all .

 

   I've changed gears from 485's to 355's and currently running 333's . And it loves to go sideways at any speed . 

 

Unless your going to drag race your truck and really put those 200+ ponies to the ground i would stick to the datsun rear end . They are easy to get gears for and cheap to .

 

I've crossed this bridge and considered narrowing a 12 bolt chevy to handle the power. I figured I would wait until I broke it to upgrade . well that was 4 years ago , and everyone thats ever rode in my truck or has been around knows I am not easy on it . . never failed me . 

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Well an 8.8 is a little different to narrow, first of all it's a clip type axle, which means it has s c clip holding it in place at the end of the axle in the diff. So when you cut the axle even s little bit, not only do you cut the splines off, but your cutting the groove off where the clip goes, on top of that, you have to machine the end of the shaft down, cus it's bigger when the splines end. Most shops won't even attempt to do that axle, even curry, if you can believe that.

One of the leaders in rear ends! So you have to re cut the groove, that's the hardest, then after machine down the shaft, cut the splines back in.

The housing is easy, any pipe fitter can do that.

Now a 9" ford is much easier, the splines on that shaft is really long, so a dimple cut and clean up the edge and that's it, then shorten the housing. Your done.

So on an 8.8 your paying for a special skill very few can and will attempt. I did my own housing, but I paid 450 for axles. Shop in LA.

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Im running 400 + hp , and I'm running a stock datsun rear end with 295/50/15's , And I have been for years without any problems at all .

 

I've changed gears from 485's to 355's and currently running 333's . And it loves to go sideways at any speed .

 

Unless your going to drag race your truck and really put those 200+ ponies to the ground i would stick to the datsun rear end . They are easy to get gears for and chap to .

 

I've crossed this bridge and considered narrowing a 12 bolt chevy to handle the power. I figured I would wait until I broke it to upgrade . well that was 4 years ago , and everyone thats ever rode in my truck or has been around knows I am not easy on it . . never failed me .

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Street tires are Not for all, you put a set of 9" slicks on that thing, after burn out it will do a cheap suit impersonation.

You did a V8, don't weak link it with a stocker one legger.

 

LSD . . . . not one legged . . . it hooks up fine , but if you've got the money to blow by all means dropping a bunch of money so you can drive 55  is a waste.  Drag racing his a whole different animal .

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