THE Bulletproof 7.5" 10-Bolt! =)
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THE Bulletproof 7.5" 10-Bolt! =)
Here locally a member of KyHorsepower has a '99 HOSS that is Procharged with a built T56 and is making over 550 rwhp on his 10 bolt. Granted that it is far from stock, his has withstood numerous 6000+ rpm dumps and stood up great. Please PLEASE do not post in this thread if you are going to knock this idea, because I know nothing mechanically is bulletproof, just please don't ruin my thread.
Anyways back on topic, I have considered building a 10 bolt for these reasons.
-Less rotational drivetrain loss
-Less weight
-And most of all FAR less money than a 9" or 12-Bolt
I just wanted to hear ProStockJohn and MadMan among others others opinions who may be running a strong 10 bolt or have knowledgable information regarding the topic.
I am wanting along with my TA Girdle...
-Solid Pinion Spacer
-Strong Aftermarket Gear
-Forged 30+ Spines
-Mini Spool (If I decide to keep it off of the streets)
-Welded Axle Tubes
-Backbrace the Housing
-C-Clip Eliminators
-And of course all new bearings and seals
Is there anything I could do to make it stronger? Is there anyone else running a similar setup?
I just want to launch off of the transbrake and have something that could hold my forged 347 with possibly a little spray.
Anyways back on topic, I have considered building a 10 bolt for these reasons.
-Less rotational drivetrain loss
-Less weight
-And most of all FAR less money than a 9" or 12-Bolt
I just wanted to hear ProStockJohn and MadMan among others others opinions who may be running a strong 10 bolt or have knowledgable information regarding the topic.
I am wanting along with my TA Girdle...
-Solid Pinion Spacer
-Strong Aftermarket Gear
-Forged 30+ Spines
-Mini Spool (If I decide to keep it off of the streets)
-Welded Axle Tubes
-Backbrace the Housing
-C-Clip Eliminators
-And of course all new bearings and seals
Is there anything I could do to make it stronger? Is there anyone else running a similar setup?
I just want to launch off of the transbrake and have something that could hold my forged 347 with possibly a little spray.
#2
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Search is really your friend. This topic has been beat to death all over this board, and yes I am going to **** all over your thread. If you can get off the internet and find a drivetrain shop, hold a 7.5" ring gear in your hand, and a 9" ring gear in the other. Then you'll realize the inherent flaw. The gear is just too small to handle abuse for any long duration.
Sure there are XX setups that did it, but you're just like the 92 year old smoker that has had 2 packs a day for the last 40 years. Yes you made it this far, but how many other 92 year old chain smokers do you see out there? Your argument is flawed because it doesn't take into account statistics, it takes into account testimony...and testimony of one person.
Build a real rearend if you want it to live under real power, all the other people in this thread will tell you to do the same.
Sure there are XX setups that did it, but you're just like the 92 year old smoker that has had 2 packs a day for the last 40 years. Yes you made it this far, but how many other 92 year old chain smokers do you see out there? Your argument is flawed because it doesn't take into account statistics, it takes into account testimony...and testimony of one person.
Build a real rearend if you want it to live under real power, all the other people in this thread will tell you to do the same.
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#3
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If you run very tall gears the angle of attack the pinion places on the ring gear becomes more favorable. You have to look at 4.10's and 2.73's side by side it will make good sense then. This is where ring gear dia makes a HUGE difference say in a 9" etc. If you can weld or have cast welded you could try and beef up the casting itself around the pinion area to try and make it a little more rigid to avoid inevitable flex. 30 spl axles in a 7.5??? Thats a new one for me but if you can get em go for it. A spool would be the only way to go.
Then after all that? Your still stuck with an inferior rear that will cost damn near the same as a 12 bolt or 9"
Good luck
Then after all that? Your still stuck with an inferior rear that will cost damn near the same as a 12 bolt or 9"
Good luck
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Yes it can be done and should hold up well for some time but seriously it will not be Far cheaper. By the time you buy the parts and fab all the bracing up you will have spent the same or more than a brand new 9" would cost.
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I ran 10.04@134 with a 1.43 60ft...Stock 10bolt with an Eaton Posi and 4.10's and a stock rear cover...Raceweight helps to the lighter the car the easier it is on parts...And also a auto will last way longer than an M6...But will still be on borrowed time...I had probably close to 200 passes on it when it finally did break...
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I ran my 7.5 for years. . no Real replacement back then.
this is how it broke down.
Every season new bearings.
Every other Season new bearings and gears and spiders.
Never hurt an Axlw and there is no reason to weld the tubes. The TQ arm is mounted to the housing so all the twisting force is contained to that area
this is how it broke down.
Every season new bearings.
Every other Season new bearings and gears and spiders.
Never hurt an Axlw and there is no reason to weld the tubes. The TQ arm is mounted to the housing so all the twisting force is contained to that area
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I ran my 7.5 for years. . no Real replacement back then.
this is how it broke down.
Every season new bearings.
Every other Season new bearings and gears and spiders.
Never hurt an Axlw and there is no reason to weld the tubes. The TQ arm is mounted to the housing so all the twisting force is contained to that area
this is how it broke down.
Every season new bearings.
Every other Season new bearings and gears and spiders.
Never hurt an Axlw and there is no reason to weld the tubes. The TQ arm is mounted to the housing so all the twisting force is contained to that area
To add, I would also have every part inside sent out for cyro. Then it stands the best chance of surviving.
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I am wanting along with my TA Girdle...
-Solid Pinion Spacer
-Strong Aftermarket Gear
-Forged 30+ Spines
-Mini Spool (If I decide to keep it off of the streets)
-Welded Axle Tubes
-Backbrace the Housing
-C-Clip Eliminators
-And of course all new bearings and seals
You are limited on axles to 28 spline unless you can find someone to make you not only custom axles but also custom cut side gears or a mini-spool for your diff. Also I am not sure what the bearing sizes are for the carrier, but a larger axle spline means a larger hole on the diff case, and the ID of the bearings might not leave enough meat on the carrier. (This led to spun bearings on 8.5's when they went 30 spline in '89 and left the OD of the bearing hub the same for a while- Eaton even upgraded their diffs to take a larger bearing.) All that would lead to a lot of extra cost- if it is even possible. A good aftermarket axle in 28 spline would still take just as much abuse as a numerically high aftermarket gear set, anything past that is kind of wasted money.
A mini spool is not strong at all, they are just cheap. You are relying on the stock case and pin which are not very strong. Aftermarket diff assemblies are stronger.
As for the welding axle tubes, solid spacer and a good quality gear and rebuild kit- that is reasonably well spent money if you can do the work yourself. Also you can pick a gear ratio and see if you like it, if you dont like it you can pick a different one when you order your 9". Everything else is just good money after bad. The girdles help, but I would save even that money for a 9".
Just my opinion. I personally run a 7.6 with a 3.90 and full weight. But I am an A4 and only run 11's. I know I am on borrowed time, but I built it myself and it may last longer than I think. But I am definitely prepared for when it breaks.
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Well I see your reasoning as I have been there. I built my last 10 bolt very close to what you have described and it held up for many many low 1.4 60fts until I sold it in fine working condition. In fact is still going strong in a local H/C car today.
I kept the stock 3.23s because they are what i considered at the time as "Bullet Proof".
I went with the H/D Eaton posi unit rather than the spool since it was a primary daily driver. I felt like the Eaton posi was the weak link even using the stock axles. I also welded the tubes and weld supported the housing as well as added LCA relocation brackets. The LCA RLB are a must. I was running a H/C 346 and only making 405 rwhp at 3480 race weight though and also an A4 with a hard hitting torque converter.
With all that said, I felt like that 94 year old Grandpa smoking 2-3 packs a day. Knowing I was about to add a good amount of power to the car with the new stroker, which would be the equivilant to being that grandpa and entering the Harley jumping contest at Bike week. It was gonna be ugly.
FWIW- I crunched the numbers and found that I spent within only a few hundreds from what a good 12 bolt rearend with a spool would have cost me.
On the other hand, if I had a light weight low 11 second car or slower race car that had a fairly soft hitting converter and the funds just were NOT there, I would consider running your 7.5" recipe. I would not consider it in an M6 car though. That's just me.
I kept the stock 3.23s because they are what i considered at the time as "Bullet Proof".
I went with the H/D Eaton posi unit rather than the spool since it was a primary daily driver. I felt like the Eaton posi was the weak link even using the stock axles. I also welded the tubes and weld supported the housing as well as added LCA relocation brackets. The LCA RLB are a must. I was running a H/C 346 and only making 405 rwhp at 3480 race weight though and also an A4 with a hard hitting torque converter.
With all that said, I felt like that 94 year old Grandpa smoking 2-3 packs a day. Knowing I was about to add a good amount of power to the car with the new stroker, which would be the equivilant to being that grandpa and entering the Harley jumping contest at Bike week. It was gonna be ugly.
FWIW- I crunched the numbers and found that I spent within only a few hundreds from what a good 12 bolt rearend with a spool would have cost me.
On the other hand, if I had a light weight low 11 second car or slower race car that had a fairly soft hitting converter and the funds just were NOT there, I would consider running your 7.5" recipe. I would not consider it in an M6 car though. That's just me.
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The deal is my car N/A will run 7.0's in the 1/8th running through a 3500 converter. I acquired a complete 9" rearend for $100 earlier today, so I believe that may change a few of my plans. But I will building my new rearend out of race shop with very little to no labor costs since I will be helping with the build up, so that should answer the labor costs questions. But regardless I know that a 10 bolts structural integrity is not near as high as a 12 bolt's or a 9"s, but I just would like to know what you could do to build it a strong as possible for a auto 11-10 second car.
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He took it to a shop and paid them right around a grand to have them rebuild his, and I would have not believed it unless I would have been able to see it with my own eyes. I just suppose he has a lot better luck than the rest of us! haha
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I just haven't been able to get a hold him lately to ask what exactly they did to his rearend so I figured I would ask some of the guys on here who have a lot more experience with our drivetrain's as to what someone would have to do to make it strong as possible.
#18
Believe it or not, there are guys who have run low 9's with a high-dollar 10-bolt back in the day. However, they are the exception and not the rule. A 9-inch makes more sense and this argument was somewhat "settled" years ago.
-James
-James
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well first thing is to keep 3.42 3.23 or 2.73 in it to keep the ring and pinion alive...next is to weld the tubes and get some moser axles... i cant keep from braking axles...local guy in the same boat he got axles and his car leacing on a 150 shot cuts 1.38 60' and has lived...i decited not to put money into this thing...so im gettin a new rear