... wonder how long it would take to digitize a diffcase. Then run over to Alcoa, get a chunk, and throw it on a 5-axis and come back in a couple of days. That would be and expensive

Last I checked my money tree was not in bloom

 

Bill..
We already did that 13 months ago (laser scanned) and we do have completed blueprints for a 6061-T6 billet aluminum case that was approx. 12lbs. heavier than the O.E. case assy., but we never put it into production due to high cost of manufacturing and uncertainty of a viable market for such an exotic, expensive piece. That was even before the metal price hike that everyone's been facing now.

IIRC, the block of billet aluminum itself weighed close to 111 lbs. and most of that ended up in the scrap heap from machining waste! We crunched the numbers back then and the approx. final cost for the just the bare case alone with matching side covers and a couple of the internal components was $2600+. These kind of parts are full tilt, full race stuff folks and my guess is that if/when one was completed, you'd start seeing halfshafts break, spindles break, wheel hubs twist off, lug nut studs shearing, etc, etc, etc... Where would it end?


Best Regards,
Phil

 

Phil (DTE),

Speaking as someone who will be finding out the weak links in his drivetrain very soon. What is the solution? Is there a "bullet-proof" solution for those that want to run a 6 spd and 7-800rwhp/rwtq and have the driveline live in a C5?

 

Yeah,

Convert over to a solid rear axle and a auto trans!!!!!!!!!!

Phil

Sorry to hear about your latest carnage.

Mike

P.S. It looks like old FLP level V 4L60 and the Getrag HD 3:42 are going to survive another year. Whew

 

phil ! this good r/d is starting to cost ya !! sorry to here this. ill cross my fingers and leave my broken driveline parked till spring to make some driveline desissions

 

What is making them fail? Is it under hard load, is it dumping the clutch at high RPM? Phil you are making me nervouse with my new HP mod..LOL
Sorry to hear that Phil.
Jon

 

Shear brute power is causing them to fail. You smack 800 plus rwtq to the driveline and this is the result. I think major spray was going through a rear diff every 3rd or 4th pass for awhile.

 

So, as long as I dont dump my clutch or track it very often, 1 or 2 times a year, I should be safe with about 650ish rwhp. You guys make me nervous...LOL but my god your HP.
Jon

 

The issue that is often times overlooked from many is that any metallic object will fatigue over time...especially when it's subjected to harsh environments. Cast aluminum (such as the Corvette differential case) is much more at risk of failure from fatigue at an increased rate than its forged counterpart, just for this reason. Typically, aluminum is brutally strong for a relatively short period of time and when it finally does fatigue to the point of yield, it doesn't just bend, it breaks/fractures like glass.

When a lower gear ratio than O.E. is installed into these cast aluminum differential cases, the outward stress loads on the case is vastly increased, because now the differential/gearing has a much higher point of leverage over the weight of the car and the differential case itself is forced to absorb a greater percentage of the torque-to-weight ratio stress than it would with numerically lower gearing. I can't remember the formula right off the cuff to figure the NM of applied force for this action, but if you saw the numbers, you would be very surprised that these differentials live as long as they do now.

This very reason is why an O.E. differential sometimes outlasts a purpose built unit due to lower internal stress loading the case experiences from the numerically lower gear ratio that is used, especially for very high torque output vehicles that consistantly launch at a high RPM from a standing start. Ironically, that is the ONLY benefit of a stocker, as they still are production line built products which are subject to a greater "window of acceptance" regarding QC control.

As a HP differential builder, we are forced to work with a cast aluminum product from the manufacturer within their very tight packaging constraints, but still provide a better, stronger differential unit than what is offered as O.E. and do it with some of the inherent issues built-in the differential design that cannot be changed. Such products and services such as hardened output shafts, cryogenically treated components, micro-polished gear sets, hardened studs, billet pinion supports and so on certainly offer a HUGE increase of differential strength over the O.E. product, but one cannot escape physics, no matter who the manufacturer is and still expect to keep the cost of production and retail within everyone's grasp. This is why we engineered the differential strut, in an effort to provide the differential case with additional strengthing devices in the areas that it needed it the most by tying all of the strongest points of the drive line together as one.

Necessity is the driver of innovation....


Best Regards,
DTE

 

I wouldn't be the least bit surprised to see you break your 4:10's. If / when they break I would go back to the 3:42's or hardened 3:73's. Also keep in mind that in general the superchargers are easier on the driveline than turbos.

Mark

 

DTE:
Do you have a link to more info on your differential strut and or an order link/page?

TIA!

 

I know you are a serious racer. If you are stepping up to the next level I think switching to an auto would be a wise choice as stated by Vetzila. I know it is expensive and time consuming but for day in and day out hammering on your car, an auto should hold much better. I swapped and it has worked for me, so far.

 

http://www.dynotech-eng.com/dte_c5_diff_strut.htm

$400 well spent IMHO.

Mark

 

so who nows if gearvenders have a C5 converion kit???? or is the c5 auto is the only way . they had a c4 kit

 

You're crazy to not go back to stock 3.42s. Who wants to pay $1800+a major pita install to have a weaker rear gear, when it won't really make you any quicker at the track (given your abundance of torque).

 

Hey twin,

I'm not serious about drag racing, If I was I sure as hell wouldnt have started with a C5!..haha
I know the score with the autos, just not willing to go to the darkside just yet.

I was concidering last spring and talked myself out of it..All the fun has really taken the wind out of my sails..

Phil

 

Hey Phil sorry to here that happened yet again you might be right with the 3.73 I have had very good luck with mine. good luck

 

I know that feeling when I snapped my trans and diff in 5 pieces... Here I had this radical new engine & S/C setup and I broke the damn drivetrain...

Jon, you are going to be in for an uphill battle with your trans and diff as well... all it will take is some serious wheel hop while on the gas and everything could break on you too.

VR

 

I agree that putting an A4 in there would cost some money, but with all of the parts he's broken already, he could've probably put in a turbo 400 with a trans brake, a good stall, and maybe even back halved the car. It sounds like he's gone through some parts. That TTi set-up must be CRAZY!!!!

 

Ok..its on the ground and apart..and on its way to the trash.
Busted the 1 side cover,main case,pinion support and of course the gears.. Only thing it missed was the one side cover..haha

Its officially a pile of junk now..