Hello vette friends.

Have a turbo vette with to much power for the stock rear axle.

Had the car since -04 and have problems with hubs, joints and the axel true the bearing.

So a 9" Ford solid axel convert is maybe the only way to go?
Checked dannysdrivetrain who have driveshafts for the c4, is there any one who have a soulition?

If the IRS gonna have a complete makeover is there any shop that has everything needed?

785rwhp 1137rwnm is the power on the wheels.

Thanks Ante

 

Save the money , sell your stuff and go with a 9 inch or a 12 bolt .. few years back i built the strongest dana 44 to be under a vette , i ended up selling it and going to a straight axel . I never broke the last dana 44 , i even got the car to 1.3x 60 foot ... but it never felt safe . i also grudge race the car and thelast thing i wanted for that thing to snap on me .

 

It all depends on what you do with the car...

If you take it down the 1/4 a LOT? I'd say a solid axle was the best way to go.

If you drive it on the roads and take it to street style tracks? An upgrade to a different IRS could be the way to go.

I am building a race car from an old C4 ZR1, and am seriously considering a modification to bolt in a Viper D44. It would have the best of both worlds...strength to hold up to serious hole-shots and the IRS for maximum wheel movement for road courses.

I know a few guys had some billet outer axles built and heat treated to correct that flaw in the design...so while anything is possible you still have to factor in the actual strength of the D44 case. As it is cast and is not the best grade of aluminum, it is prone to failure when stressed.

P.S. Some of the things I've seen that work on a C4 D44 that seemed to work was a snubber on the front of the differential. I saw one guy actually use a plate with threaded nuts on top and used the C-beam bolts to make it one solid piece going to the frame.

Many ways to skin that cat...but your daily use of the car will determine the best route to go.

I wish Denny's would have continued their R&D on their billet D44 case...completely CNC'd but the cost would have made it VERY expensive to do since it WAS from a solid block of aluminum and so much was thrown away in the machining process.

 

Well, I only take it to track 2 times each year, but thats just because I know it will failure.
It's a daily driver, Only trail queen when it goes bad on track.

But a solid axel with wattlink and 3-link will work fine at the track and still have god handling at the street I think.

A rebuilt on a dana 44 cost about 4500$, à solid axel 3000$ + I maybe can get 7-1000$ for mine.

Do you guys know who to contact to get à solid 9"? Will do the link system my self, a clean axel with Detroit locker with right width, brakes

 

http://vettesuspension.com/

not sure if they still offer the kit ..

 

With that kind of power Id def. do a straight axle keep us posted.

 

I just installed a solid rear end with the watts linkage and a three link setup. I blew up my motor during the first auto-cross I went to so I only have three runs on it. I was giving it he'll to see what it would do. I am happy so far with it I just am install the new 467 small block this weekend so I will probably finish it next weekend.

 

Fix the irs and get the best of both worlds.

If you have the skills to put in a solid axle, you have the skills to fix the irs (upgrade stub ends, half shafts, pinion snubber, extend bump stops 1", etc.)

There was a c6 guy who ran 7's? On the irs.

Don't forget the many c3 guys running crazy times on their irs.

Unless your goal is a 6 second quarter mile, id stay with irs.

A solid axle (I think) wld take away from the corvtte personality of your car.

 

You can't compare the C3/C6 IRS to the C4. If it was easy to make the C4 as strong as C3 it would have been done years ago. I spoke to Tom Differential years ago and they were not interested in the C4 IRS. No aftermarket company seems really want to redesign it so it can handle some power. Now if I had $15,000, there is a company in Florida that would make me one that can handle 950 - 1000 HP at rear. I have to wait for the lottery to go my way.

 

"You cant compare the C3/C6 IRS to the C4"

Yes you can, it shows that it can be done. Everyone acts like the C4 has some kind of 'you cant mod me, I am slow' demon in it that you cant get rid of no matter how hard you try. Ive gotten into this before, particularly with some users of this site. It is just a hunk of metal/plastic like any other car.

With enough skill, and determination you can make it work. If you cant make stuff (or get stuff made for you), and need an off-the-shelf drop-in replacement, then yes you are out of luck.

so you can spend $5000 for a solid rear. I bet you could take that same amount of money and fix the IRS. Maybe you will surprise yourself.

Hire someone to install a cage, take a welding class (to build a snubber), find people who know how to machine the right 'case'.

Theres a dude here (AKS Racing) running low 9's on his supercharged C4 IRS - and thats just one guy I know of. He built a liter-bike stomper and it does just that. He runs stock halfshafts too.There is prob more that I dont know of.

Dumping at 6k on slicks w/ a non-sprung hub clutch (like Mcleod Street twin) is just asking to break stuff.

Its also funny all the people who act like the D44 is a wimp. People with D36's, it seems, would give a limb to get a hold of a D44.

All this said:
I will concede that if your goal is mid single digit quarter mile, then solid rear is your only option.

 

Show us 1 C4 with an stock style IRS Rear that stands on the rear bumper on launch & does it with both front wheels for 200 feet off the starting line, front end of the car pointing near 90 degrees towards the sky..............

Then this same C4 wins the Byron, IL World Outlaw Wheelie Contest,
gets on the front cover of Hotrod & Car Craft magazine, National Dragster Magizine, & covered on ESPN, Pinks TV, does all this without breaking ever.
Full Blown Nitrous, Twin Turbo, Supercharged 2,000 + Horsepower launches.......

Then I am sold on a C4 IRS stock based rear setup for drag racing.

Now if the IRS fails in your C4 when your motivating down the 1/4 mile at over 140 mph & you hit the wall,
You just may flip upside down, endo end over end several times.
That will get you on the cover of National Dragster Magazine too.

But not if you die in the process because you were too stupid to switch over to a solid axle 4- link rear diff setup.

 

My goals are not 2000+ HP and to do wheel stands 200 ft down the track.

Nowhere did I state that.

in fact, I clearly state that I concede that if 6 seconds 1/4 miles are your goals, then I dont think ANY IRS (C6, C3, viper, etc.) is going to be correct for that application.

As for a driveline failure at 140 MPH. Very rare. Its going to happen right at the launch when TQ is at its maximum due to the gearing.

My point here is that the C4 IRS CAN be fixed, just like it has been on C3's, C5's, C6's.

is it optimum for drag racing? No. A solid rear is always the better choice if that is the only place you ever plan on racing it. My next question would be: Why do you have a corvette? Most people heres ultimate goal would be to run 9's. This is where my goals fit in. I think you can get there on IRS-equipped C4. Aaron at AKS Racing is one such member that does this regularly on his stock halfshaft D44. A stickshift car to boot.

Maybe we should ask the OP what his goals are to better answer his question?

 

 

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Unless you plan on running faster than that in the quarter (which I seriously doubt) - I'd say the Dana 44 can be built to withstand just about any amount of power you're ever likely to make.

It wouldn't be cheap I'm sure, but that's besides the point. The IRS set-up CAN be made to handle serious power and hard launches, that's a fact.


The real question is whether a solid axle swap is a more cost effective option than building up the IRS. That's what you need to figure out and go from there.

Having said that, I would assume a solid rear swap would be the "easier" option due to the fact that there are already places that offer up a complete solid-rear package for the C4. You'd be able to do everything in one shot without having to shop around hunting for parts.

Building up a Dana 44 properly on the other hand, may prove to be more difficult since there probably aren't as many places/people that have the know-how to build up the 44 to begin with. But they are out their. It's just a matter of finding them...

 

In my opinion if you street drive it more than you race it as you indicated, the solid axle is a bad choice.

 

There are 3 5.0 Mustangs running faster than that C4 in Chi Town area.
Street driven too.
8.60's & faster.
All solid axle cars.
Handle & ride surprising well too on the street.
All 3 ran 8.60's or better since 2004.
All 3 rear 8.8" Diffs built by 1 mechanic that you just may have heard of.

The rare & unfortunate does happen going down the 1/4 mile.
Most rear diff & hardware failures do happen at launch.
But not all.
When they do happen motivating down the 1/4 mile at speed,
its real bad.

See you at the NHRA Fastest Street Car Shoot out with your stock based Dana 44 IRS C4 then.

If you don't break ever in the heat of battle,
you just may win & claim Fastest Street Car Title in the entire world.

 

Theres a dude here (AKS Racing) running low 9's on his supercharged C4 IRS - and thats just one guy I know of. He built a liter-bike stomper and it does just that. He runs stock halfshafts too.There is prob more that I dont know of.



Actually,( And I mean no disrespect to AKS Racing when I say this,) the kind of power he is making justifys a solid axle if drag racing is your cup of tea, or you dont want to baby the car every time you launch it. Look at his times he shows in the sticky links at the top of this forum. MPH 153 9.34 et. but only a 1.82 60ft time. Now with that kind of power, if he could leave without babying the car off the line, he would be down in the 8's with a 1.2 or so 60ft. In other words, he is probably leaving close to a second on the table due to the IRS rear end.
IMO his times really show nothing good about the IRS rear, but it sure does show he has a strong motor

But back to the OP question, carrolls rod and racecraft makes a 4 link 12bolt solid axle conversion. Then there is the one linked above from vette suspension, aka ski dwn it. Do a little research on them in the drag racing section of this forum, and I believe you will want to stay far away from ski dwn it.

 

By the time you build a dana 44 to hang in the 9s, you will have more money into the thing than solid axle conversion . I built a 9 sec dana 44 , it cost me over 3000$ for the center section alone, only reason i put that much money into it was because no one did a solid kit for are cars at that time . I ran the dana 44 for a year , almost hit the wall due to U joint failure , took the car home that day and started cutting the car for the solid axle .. Dont waste your time and money with a dana 44, unless you wanna baby the car off the line like that one turbo car in the post above.

 

Then go out and get a 5.0 then if you think they are so better. Where did I say I'm looking to claim a title for the fastest street car?

Id rather have the c4 (w/ irs) running 8.97 then a solid axle 5.0 running 8.60

-or-

Id rather have aaron at aks racings car running low 9s w/ an irs vs. His car runnng low 8s w/ a solid rear.

Its clear we disagree and I'm sure we can agree at that.

The op needs to be aware that there are different ways of thinking.

 

Did you extend your bump stops by an inch to prevent the u joints from allowing the half shafts to create too much of angle during launch?



Its kind of like a swivel joint on a socket, the more angle you have, the more likely it is to break