so after the procharger, heads, cam, exhaust....if i want to run drag radials and take it down the track...weak link now is the drivetrain..right?..so..tell me about that project..what to change, beef up, etc. thanks..

 

Check these guys out www.dynotech-eng.com

 

In looking at their addr, I see it's right down the road from my summer res in Ft Wayne, IN. This is something I really need to start considering too if I ever decide to do any dragging with my LPE 427.

 

I talked to DynoTech Engineering today. Yes, the Corvette has a girlieman drive train! They don't make a "differential strut" for the 2006 C6 with the six speed automatic yet, but plan to have one in about two months (they make one for the manual).

I was told that Chevrolet said that to beef up the rear end would have added too much money to the per unit cost. I would have been willing to pay for a beefed up rear end with a warranty instead of buying after market stuff.

When I was a young buck, I ran a '62 406 Impala with a four speed and a 4:56 positraction. The horsepower was way too much for the rear end and I constantly broke the third member. I got to the point where I could change a third member in thirty minutes. The rear end wasn’t beefy enough for the horsepower. Nothing has changed at GM in forty years!

Back to the vette. It's my understanding that if we want to be happy campers, we should at least put on a "differential strut." The better solution is to bite the bullet and buy a beefed up rear end, spending about three grand.

Craig
Clackamas (Portland), OR

 

You would be fine with a hardend driveshaft and tires that give in alittle before the rear. There is no good solution IMO right now to replace or help the weak diff case that I know of. Unless you mod out for a C5 Z06 rear diff.

 

check out forum sponsor www.cartek.net they have a lot of cars with chargers turbos nitrous in the 9 second range with no drive train problems

 

In talking to John @21st yesterday, he said if I wanted to use the 'ol "ounce of prevention" philosophy for my 427, I could install a stronger (hardened?) right output shaft. Apparently that's the most vulnerable side. Is that the same as a driveshaft? Can you tell I'm no mechanic?

 

i think its in the rear and the shaft slips in it or over it never seen one

 

C5 rearend here, built by ECS, installed by 21st CMC... I have a Z51 MN6 ECS did all the cool stuff 4.10's, output shafts, etc etc... The C5 rear is the way to go... holding my 8psi and N2O combo...
Jeremy

 

All the talk about beefing up with output shafts is nonsense since it is the cases breaking and not the shafts. If you spend 2k on a built up diff with all that crap the case will still crack with any real TQ on a prepped track....period.

The advantage of the C5 cases is that the C5 core is far cheaper and they dont have the two arms connecting it to the cradle. Some tuners actually try saying the arms are part of the support but they simply give the wishbone factor into the mix. These cases crack right up the middle. The C5 rear has a center mount but real tuners that build track cars such as Cartek report that the C5 rear breaks too. I'd rather break a 700 dollar core than a 2200 dollar core.

 

What would you, (or anyone else for that matter), recommend I do to my C6 rear after installing a 575 hp 427? John @21st MC doesn't seem to think I need to do anything if I'm not a drag racer or use super sticky street tires. I'm not a drag racer now, but I do want to try it, nor do I use super sticky street tires at the moment. Actually going to finish off the OEM GY's. Is this idea of replacing the right output shaft with a beefier one, really a waste of good money?

 

Well the guys in my club with big horsepower do get the build ups from dynotech, and they do offer billet end caps that do strengthen the casing a bit, and the hardened drive shafts all around lead towards less overall flex, then they cap it off with Differential strut brace. But still after doing all that I have seen them grenade the case! One guy, made a cast iron version of the rear diff, and its holding up to a 9 second vette right now. He actually did it in the metal shop in the high school he teaches at. I wonder if they could start mass producing that. Why does the case have to be made of aluminum. Screw aluminum and the couple of pounds it saves if it can't hold the power that people put into their cars. If you have like 550hp, what does adding 20lbs mean to you, probably not a damn thing.

For the other guys, they just still kind of baby it off the line a bit.

 

It sounds too simple to replace the aluminum case with a "cast iron" case, but then again sometimes the simplest fix is the best. Is anyone making a cast iron replacement case for sale?

It appears that some have the problem while others do not. This could be attributed to the driver, but I really believe it is the weak, aluminum case causing of the problem.

Once again, can a guy find a cast iron case? Hey, GM are you reading this?

Craig
Clackamas (Portland), OR

 

Yank verified they are developing an iron case but its not ready yet and the completed diff will be 5k.

I havent seen any shafts breaking with guys I personally know that had failures. Most guys report that they simply swap the internals to a new case and they are back on the road.

The cases are breaking (almost every time) right up the middle....not at the end caps, not at the output shafts and not from the transmission mounts. Those issues come after the case cracks and deforms the internals taking them with the rest of the damage. I have seen diffs crack on c5's with the dte brace. Aitqik's diff blew up and with the 100 peices recovered, his STOCK output shafts were surviving peices. Mind you he had the thin 2005 output shaft and not the thicker one as in the 2006+.
I have seen few people head to the track with a upgraded diff since they learn their lesson the first time around. Failures will be at the same rate.

Built rears still use the cast cases and are no stronger than the stock case....even deburred.

 

When the differential goes, does it damage the bottom and other areas of the car? When I raced my 409, we had to have "scatter" plates around the bell housing to stop the clutch, pressure plate and bell housing from blowing through the floor board causing serious injuring. I rode with a friend who had a 406 Ford without a scatter shield when his clutch blew. We were lucky and didn't get hurt but, man, did it do some serious interior damage.

Back to the issue: Should we have some kind of scatter plate around the differential?

Craig
Calackamas, OR

 

OUCH...
I guess since I run my car weekly, that still doesn't qualify ECS, or 21st CMC as two of the "real tuners"??? A LOT more luck with the C5 this go around, than my C6 rear... Just, my experience, on my car...
Jeremy

 

I didn't do much damamge to the under side at all.... BUT I did it at launch and was not moving fast. I imagine at 6000 rpm and 100+ mph it could have been ugly. I blew the the back of the diff completely off. The sides are in tact and still hooked to the mounts with no cracks at all.

I would like to know who you talked to at DTE, because I talked at length to Jenny, and she said there are no hardened sides that they make to the case, not any case modifications to the case at all. which, as Spin says, will not really help my problem. Driving it easy will prevent it but why build a 600 horsepower car to drive it easy? There is no, and I repeat no, case modifications out there from any company that I have found. The DTE brace is it. The case is crap and it will crack if you beat on it period dot end of story. LPE says you don't need to worry about the case? Really? Their turbo car blew the case during the shootout. If you don't race or launch the car ok, I'll buy that, but that's the same thing as saying if I don't have sex I'll never be a father. In my opinion a road race car does not need to worry MUCH about the case. Different forces. Might go, but less likely than the launch situation.

 

We manufacture HD side covers for the C5 Corvette platform which the competition has blatently copied using inferior engineering compared to our product. (Come to our PRI booths and see our new products for yourself up close and you'll see what we mean...) However, we have no HD side covers for the C6 Corvette ...yet.

That is incorrect, we do quite a lot of internal modifications, but she isn't going to release what we do, nor how we do things to a complete stranger on the telephone. We've been stung doing that before, so we won't make that mistake again...

See above reply.

We have a whole host of new products that will be displayed at the PRI show in 1 week from today. We quit posting our new products here because then our competition shamelessly copies our products and claims the design to be theirs and is "new". If any of you that have any doubts about our products in any capacity, we challenge you to drop by our booths, identify yourself and we'll gladly show you everything we have~ describing the engineering reasons for our design so you can then judge for yourself *AFTER* you've seen/held/understand the product for yourself.

Many folks have doubted our products in the past, but once they had an opportunity to set down with us to understand what we're doing, why we engineer our products the way we do and hold/use the product for themselves, they often switch to using our products with success. Many other tuners even doubted our products when they first came out and once they called to find out about us and our products, they now understand where we're coming from and use our products in their performance packages as well. Even some of the tuners that build their own differentials use our internal HD products.

Our booth numbers are #5940-5942.

 

I didn't ask what you do or how you do it, I asked if you guys do anything to the case to make it stronger. She said no. I'm not Yank and I'm not trying to steal your products, I'm trying to purchase them. A yes would have been fine. A "we polish the insides" would have been fine. I got no, we don't do anything to strengthen the case. I know you make HD side plates for the C5, I asked about C6 and was told no. I know you are working on them.

I'm not sure why you are attacking me, I'm simply passing on what I was told when I made inquiries. Since you are throwing challenges, I'll one up you. I'll come to PRI, receive whatever you sell, and shatter it on street tires. I'll launch the car below 2500 rpms. I'll put on your brace. I'll immediately get out of any wheel hop. I won't try to break it. All on my lil naturally aspirated motor. If it doesn't break, I'll become your poster boy and shut all these people up.

I know that's a dumb thing to say, but look at it from our point of veiw. I'm a poor service member. Why would I buy something for $5k that is just as likely to explode as the thing I already exploded? Why would I buy something for $5k that is even 20% less likely to explode than the thing I just exploded. Why should I have to prove to your company that your product works, you guys prove it to me. Look at the pictures, hold it in my hand does not prove a damn thing to me. I think you have great products. I think you know what you are doing. I think you are a swell, helluva guy. I don't think your HD internals and cool braces will keep me from blowing the thing up. I asked your company to help convince me otherwise and they told me your products won't help me from shattering the case. I won't break a shaft, but I'll still break the case if I get the slightest amount of wheel hop.

 

AINTQUICK