Which diff for 600hp?
Race Director
Joined: Jan 2003
Posts: 15,174
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From: State of Confusion
Moser Engineering has been fabbing 9"-Fords for Camaros, Chevelles, and Monte Carlos for years, with all the tabs & brackets on the housing for a bolt-in swap:
how-hard would it be for them to do this for a C3, w/ attatched 4-link brackets & shock-mounts?
Le Mans Master
Joined: Oct 2002
Posts: 5,714
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From: Silver City NM
St. Jude Donor '05-'07
Glen: Don't get me wrong...I wish I could do the exact same thing (with a spool instead of a locker). I don't even know if there are any shops in my area that can do something like that. Probably have to trailer mine to Texas or California or somewhere. 
Yellow73SB: Only Dana 60s I ever heard of breaking were very rarely on Pro Stock hemi cars in the early 70s. I did a search on the rear end you mentioned and they appear to be popular with off road 4X4 people. Wasn't able to find any mention of the 14BFF being used in strip cars. The Chevy S-10 rear end also seems to be popular for drag racing applications.
Dep
Yellow73SB: Only Dana 60s I ever heard of breaking were very rarely on Pro Stock hemi cars in the early 70s. I did a search on the rear end you mentioned and they appear to be popular with off road 4X4 people. Wasn't able to find any mention of the 14BFF being used in strip cars. The Chevy S-10 rear end also seems to be popular for drag racing applications.
Dep
Le Mans Master
Joined: Nov 2004
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St. Jude Donor '07
Probably becuase the 14BFF weighs probably 300 pounds 
Never heard of one breaking. I'll be putting a D60 in the front If I ever find one at the junkyard. 39.5 tires. It's an old truck we had in storage and I've been driving it off road. It's fun to run over anything you want
Never heard of one breaking. I'll be putting a D60 in the front If I ever find one at the junkyard. 39.5 tires. It's an old truck we had in storage and I've been driving it off road. It's fun to run over anything you want
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
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Then there are the sick folks like me who convert a brand new NOS never had axle tubes pressed in...Hemi Dana 60 into an IRS setup!! Mopar guys cringe!!
But it's been under mine for a long time now and has taken a LOT of abuse without a whimper. Yes it's heavy..but I haven't touched it...even with 700 ft lbs and 5000-6000 rpm sidesteps on slicks!
JIM
But it's been under mine for a long time now and has taken a LOT of abuse without a whimper. Yes it's heavy..but I haven't touched it...even with 700 ft lbs and 5000-6000 rpm sidesteps on slicks!
JIM
Race Director
Joined: Jan 2003
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From: State of Confusion
Drifting
Joined: Jun 2002
Posts: 1,620
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From: Orlando Florida
Then there are the sick folks like me who convert a brand new NOS never had axle tubes pressed in...Hemi Dana 60 into an IRS setup!! Mopar guys cringe!!
But it's been under mine for a long time now and has taken a LOT of abuse without a whimper. Yes it's heavy..but I haven't touched it...even with 700 ft lbs and 5000-6000 rpm sidesteps on slicks!
JIM
But it's been under mine for a long time now and has taken a LOT of abuse without a whimper. Yes it's heavy..but I haven't touched it...even with 700 ft lbs and 5000-6000 rpm sidesteps on slicks!
JIM
Sounds cool
Instructor
Joined: May 2006
Posts: 191
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From: TEXAS
Now I maybe missing something here, but It seems to me that installing a 12 bolt ring and pinion yourself would not be too hard of a task. Tom's differentials sells the special 12 bolt ring and pinions seperatly. after that you just need to grind out with carbide cutters the clearance for the larger ring. Then add those heavy duty caps and get a set of 30 spline axles from van steel. Set up the gear mesh right and your good to go. Using a spool would be cheaper or maybe a locker. I calculated it would cost half less than having Tom's do it for you.
Last edited by msb184; Apr 18, 2007 at 12:07 AM.
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Team Owner
Joined: Jul 2001
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From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Most of the failed C3 rear ends are caused by excessive squatting due to a too soft spring or inadequate shocks..
Le Mans Master
Joined: Oct 2002
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From: Silver City NM
St. Jude Donor '05-'07
The axles are designed to hold up to rotational force. If for any reason the geometry is off or the rear spring is too soft and squats excessively, the geometry can get messed up and a there will be some force pulling the axles etc... I doubt that this can happen with a properly set up rear suspension (very tight rear spring and shocks and all the geometry set up correctly)
Most of the failed C3 rear ends are caused by excessive squatting due to a too soft spring or inadequate shocks..
Most of the failed C3 rear ends are caused by excessive squatting due to a too soft spring or inadequate shocks..
Le Mans Master
Joined: Apr 2000
Posts: 7,562
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From: B'Ville NY
Cruise-In III Veteran
St. Jude Donor '05
Hey all, I have the VB&P Street & Slalom suspension kit under my car which comes with a 360 lb rear spring FWIW. That axle did break with my street tires on taking off without dumping the clutch. I'd be interested in knowing more about the possibility of geometry being off. I've had my car aligned professionally so the tires should be pointing in the correct position as far as that goes. My shocks are Carrara adjustables. I built my vette more for autocross and street handling so I do admit that it is not ideal for the strip.
I may have just gotten a faulty axle, but it does have me a bit gun shy. I will say that Tom's replaced the axle free of charge and were excellent to work with. I also bought my posi from them which is suppose to be "tuned" with kevlar clutches and doesn't have the spring kit installed like the stock units.
I may have just gotten a faulty axle, but it does have me a bit gun shy. I will say that Tom's replaced the axle free of charge and were excellent to work with. I also bought my posi from them which is suppose to be "tuned" with kevlar clutches and doesn't have the spring kit installed like the stock units.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
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I'll need to take some more of it. I lost all the original ones in a computer crash.
I found another one out of an old Super Stocker Vette a couple of years ago. The guy had bought it used about 15 years before that and had been racing it ever since. When he got it he got an extra halfshaft and some other odds and ends....never needed any of it. He had recently converted his car to a solid 12 bolt axle because *it was lighter...and supposed to be faster*. Turns out car slowed down a tenth with identical gearing! It was still lifting front wheels like before...but all the IRS horror stories seem to be a little unfounded.
Vettemaniac here on the Forum bought it to install under his C-3 with a 638" motor. All we need to do is change gears.
JIM
I found another one out of an old Super Stocker Vette a couple of years ago. The guy had bought it used about 15 years before that and had been racing it ever since. When he got it he got an extra halfshaft and some other odds and ends....never needed any of it. He had recently converted his car to a solid 12 bolt axle because *it was lighter...and supposed to be faster*. Turns out car slowed down a tenth with identical gearing! It was still lifting front wheels like before...but all the IRS horror stories seem to be a little unfounded.
Vettemaniac here on the Forum bought it to install under his C-3 with a 638" motor. All we need to do is change gears.
JIM
Team Owner
Joined: Jul 2001
Posts: 182,997
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From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Hey all, I have the VB&P Street & Slalom suspension kit under my car which comes with a 360 lb rear spring FWIW. That axle did break with my street tires on taking off without dumping the clutch. I'd be interested in knowing more about the possibility of geometry being off. I've had my car aligned professionally so the tires should be pointing in the correct position as far as that goes. My shocks are Carrara adjustables. I built my vette more for autocross and street handling so I do admit that it is not ideal for the strip.
I may have just gotten a faulty axle, but it does have me a bit gun shy. I will say that Tom's replaced the axle free of charge and were excellent to work with. I also bought my posi from them which is suppose to be "tuned" with kevlar clutches and doesn't have the spring kit installed like the stock units.
I may have just gotten a faulty axle, but it does have me a bit gun shy. I will say that Tom's replaced the axle free of charge and were excellent to work with. I also bought my posi from them which is suppose to be "tuned" with kevlar clutches and doesn't have the spring kit installed like the stock units.
IMHO, 360 lbs/inch spring is too soft UNLESS you are using QA1's set to at least 8 - 9 clicks.. If you have tight shocks, it might have really been a faulty axle.. I've never seen one of those break before.. The axle is actually the only thing similar to a solid axle car.. The place your s broke would also be possible with a solid axle.. Yours actually broke at the place where it should be strongest.. If for any reason your suspension was too soft, it is possible that the half shafts pulled too much at the axle which caused a combination of rotational and pulling force which caused it to break.. My rear end is setup to have a maximum travel of about 1 inch on launch. Therefore my geometry doesn't get messed up on launch..
Burning Brakes
Joined: Mar 2005
Posts: 1,139
Likes: 0
From: Salina Kansas
I bought a 'dragvette' 6-link setup and am going to run it with some 17 splined, flanged, stubshafts on order from Vansteel. High 10's for several seasons with 1.45 sec 60' times are claimed with an otherwise stock rearend with this 6-link setup, so I guess I will see if I can do the same...
J/K
