The diff went bye bye
Le Mans Master
Joined: Mar 2001
Posts: 6,210
Likes: 987
From: Watkinsville, GA and Glen Cove, NY
Pro
Joined: Nov 2007
Posts: 710
Likes: 0
From: Northern Florida
Well I knew the day would come and it did. I haven't posted in a while because I was having lots of fun with this procharged engine. I took it out late at night gave it few hard punches and BOOM. It felt like a mini bomb went off in the back of my car. My headliner feel off and hit me in the head. It seemed as if the 4 speed popped itself out of gear. I went to put it back into gear and there was nothing but revs. RUH ROH! I pull it off to the side of the road and of course I see my driver side tire **** eyed. Needless to say I became a triple A member that night. LOL I get the car in the garage late this summer and jack it up and I see the axle stub sticking out about an inch further than it should.
Now that you all are up to speed, I'm at a crossroads here. The engine is making 800 or so at the crank. Is it even worth rebuilding one of these diffs myself with the Duntov axle stubs, using richmond gear with that rem coating and possibly reusing the eaton posi? Or do I have to shell out the big bucks and convert to solid rear axle? The autofab one I like, but I just wish I could order a solid rear and bolt it into my car and not have to pay someone to weld on my car and hope its all straight. What do you think?
I have heard of a shop called Carrols that is possibly in development of a bolt in kit. At least that is what there site says but they never return my emails or my calls.
Now that you all are up to speed, I'm at a crossroads here. The engine is making 800 or so at the crank. Is it even worth rebuilding one of these diffs myself with the Duntov axle stubs, using richmond gear with that rem coating and possibly reusing the eaton posi? Or do I have to shell out the big bucks and convert to solid rear axle? The autofab one I like, but I just wish I could order a solid rear and bolt it into my car and not have to pay someone to weld on my car and hope its all straight. What do you think?
I have heard of a shop called Carrols that is possibly in development of a bolt in kit. At least that is what there site says but they never return my emails or my calls.
Im running about 550 h.p . at the crank with 600 ft.lbs torque on my 1970 BB Vette with M21 and i think the street radials are saving my rear end.
Melting Slicks
Joined: Jul 2006
Posts: 2,373
Likes: 6
From: Baltimore MD
I havent read your entire thread thru, but, im VERY curious to know what kind of tires you are running ? If your running standard street radials, im surprised that the rear tires didnt act as a safety valve and just spin without hooking. Or...are you running some sticky tires which is a different story (?) .
Im running about 550 h.p . at the crank with 600 ft.lbs torque on my 1970 BB Vette with M21 and i think the street radials are saving my rear end.
Im running about 550 h.p . at the crank with 600 ft.lbs torque on my 1970 BB Vette with M21 and i think the street radials are saving my rear end.
Last edited by Billysvette; Jan 2, 2011 at 11:15 AM.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
It's my first hand experience (more than once) that you do NOT have to be on slicks to break a 10-bolt or other IRS bits. I've broken spiders, pinion shafts, cracked cases and had various parts spit out thru housings. 
Thread Starter
Instructor
Joined: May 2006
Posts: 175
Likes: 0
Hey guys sorry I have been away for a while. To answer some questions yes it runs mickey thompson et streets all day every day. I have increased the boost at 16 lbs and am estimating mid 700 to 800 crank hp. It needs a new chassis dyno since modifications have been made with programmable timing from msd with boost retard curve.
I'm interested in the Duntov axle stubs. I have spoke with them and they have claimed to run 900hp cars on there rear ends. I'm leaning towards possibly buying the parts and assembling it myself. Does anyone else have experience with their REM coated gears 400lbs springs, and super heavy duty axle stubs?
I will have the carnage pics up tonight!!!!!
I'm interested in the Duntov axle stubs. I have spoke with them and they have claimed to run 900hp cars on there rear ends. I'm leaning towards possibly buying the parts and assembling it myself. Does anyone else have experience with their REM coated gears 400lbs springs, and super heavy duty axle stubs?
I will have the carnage pics up tonight!!!!!
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
10 Things C8 Corvette Owners Hate (But Won't Tell You)
Joe Kucinski
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!
Brett Foote
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)
Joe Kucinski
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!
Michael S. Palmer
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!
Joe Kucinski
7 Bolt-On Upgrades From Extreme Online Store to Level Up Your C6 Corvette
Pouria Savadkouei
Thread Starter
Instructor
Joined: May 2006
Posts: 175
Likes: 0
http://i976.photobucket.com/albums/a...e/100_0015.jpg
http://i976.photobucket.com/albums/a...e/100_0014.jpg
http://i976.photobucket.com/albums/a...rvette/161.jpg
http://i976.photobucket.com/albums/a...icrevision.jpg
http://i976.photobucket.com/albums/a...e/100_0014.jpg
http://i976.photobucket.com/albums/a...rvette/161.jpg
http://i976.photobucket.com/albums/a...icrevision.jpg
Last edited by supervette2; Mar 21, 2011 at 07:12 PM.
Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
You need a 12 bolt.....no doubt about it....800hp and a stick? Hell I would be suprised if a 12 bolt even holds together. You DEFINITELY need Toms 31 spline outer axles and 30 spline inners.... I wouldn't waste the money on Duntov stuff..... There is a big thread at Digital Corvettes going on about a Duntov rear that was brand new that disentigrated with way less power then you have
At the VERY minimum I would do a Super 10 bolt from Mike Dyers or Gary Ramadei and go back to regular radials...
I have a Super 10 bolt with Toms axles and it has held up fine so far to 650/650 but this is in an automatic.....whole different ball game....
At the VERY minimum I would do a Super 10 bolt from Mike Dyers or Gary Ramadei and go back to regular radials...
I have a Super 10 bolt with Toms axles and it has held up fine so far to 650/650 but this is in an automatic.....whole different ball game....
Thread Starter
Instructor
Joined: May 2006
Posts: 175
Likes: 0
I couldn't imagine going back to regular tires, the hookup is addicting. That's what I was afraid of is that the duntov wouldn't be strong enough. If these vettes are cracking differentials I wonder if I should wait for toms Billiet case to come out? Its too bad that case doesnt come out until next summer. Or it's back to the accufab kit?
Thread Starter
Instructor
Joined: May 2006
Posts: 175
Likes: 0
I have thought about attempting to modify my own diff with toms parts. I'm unclear of what tools are used to clearance the housing? I have Plenty of time to do this right. Any thoughts or suggestions?
Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
Toms has been advertising the billet case for like 5 years, "next summer" is always said..... it ain't coming.... aside from that, the housing is not the problem, its everything inside of it. Build you a good iron diff, 12 bolt guts(Tom's is the only show in town for these special parts....they are not just regular 12 bolt parts....its specially machined stuff)...
To build a full mojo 12 bolt conversion with all the goodies is about $6500.....it really needs to be assembled by someone who builds them regularly....they are quite different beasts from regular 12 bolts.....LOTS of machining, clearancing, blue printing etc.....
I wanted to do a 12 bolt but a 3.73 was the tallest gear available. I wanted to run a 3.36 so I had to build a Super 10 bolt instead.....not to mention it was $2k cheaper....
I still spent $4500 on it though....
Here was my build thread with all the pics/info...
http://forums.corvetteforum.com/c3-t...-build-up.html
To build a full mojo 12 bolt conversion with all the goodies is about $6500.....it really needs to be assembled by someone who builds them regularly....they are quite different beasts from regular 12 bolts.....LOTS of machining, clearancing, blue printing etc.....
I wanted to do a 12 bolt but a 3.73 was the tallest gear available. I wanted to run a 3.36 so I had to build a Super 10 bolt instead.....not to mention it was $2k cheaper....
I still spent $4500 on it though....
Here was my build thread with all the pics/info...
http://forums.corvetteforum.com/c3-t...-build-up.html
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
I'm interested in the Duntov axle stubs. I have spoke with them and they have claimed to run 900hp cars on there rear ends. I'm leaning towards possibly buying the parts and assembling it myself. Does anyone else have experience with their REM coated gears 400lbs springs, and super heavy duty axle stubs?
Don't even consider running 17 spline stub axles regardless of what they are claiming. With the power you are making you will twist them. Add to it that you're running a standard trans greatly magnifies the shock load. You cannot run 400 lb springs without using the non-engaging carbon fiber clutches. Which is a moot point since you should not be running the preload springs at all. They are to aid the clutches in low load situations hence the name preload.
You've also gone past the Super 10 option. The carrier won't handle the load and shock for very long. In your pic it looks like you have lost the front pinion bearing which is why the carrier is chewed up. Looking at the next to last pic I can see that your clutches are shot and the spider gears are worn out. A rough guess is that you have at least 4-5 times the maximum allowed spider gear backlash.
To do the 12 bolt conversion you will need a lathe, a mill, and a surface grinder. There is a tremendous amount of machining that has to be done just to make the parts fit. The carrier shims have to be made, the original design won't work. You also need to ugrade your driveshaft to 1350 joints. Those 1330's won't last long. Next to go will be the outer spindles and the the halfshafts.
Mike