You are incorrect, it is common practice to stress a part to failure. If you don't know where the failure point is there is no sense testing a part to begin with. Common sense tells you to replace a part that is showing wear, but internals are not constantly checked with the exception of F1, some Rolex teams and perhaps Nascar.

We will be putting a diff cooler on in the next few weeks. I'll pass the info on to Rob and it'll be up to him what he wants to do.

 

You say I am incorrect and then you go about agreeing with most of my points.

Everyone knows that parts are routinely stressed to failure.

What is the point of testing something as you say when you know when it will fail. Why would you bother, just to prove you were correct?

I thought I had said that the pros check and replace parts before they fail in use.

Anyway, any discussion with you is liable to get you to delete all your posts on the subject, just as you did last time.

 

You are incorrect about "pros" not letting their parts get to the point of failing. They routinely do this so they know what the part can handle and what situation will expedite a failure.

Finally something we agree on

In a lot of situations you do not know all the factors that contribute to a part failing. The reason you "bother" is so you know exactly where it fails, how it fails and ALL the contributing factors for the failure

Again, not all pros check the internals of all parts, such as the ring and pinion, every time out. A lot of times a simple drain and metal check along with pulling the cover for a quick visual inspection is all that's done. I'll give you an example, we had a Grand Am team testing at our track. They tested on a Tuesday, pulled all fluids Tuesday night, visually inspected the car and loaded it Wednesday morning and took it to the West coast and raced it on Saturday. They didn't disassemble the whole car so they could check for every micro crack on every piece of the car. You are making a generalized statement on a subject you know very little about.

I only came back because there are some good people on here, and we have made some major improvements on this chassis within the last 12 months. I also have the advantage of being able to talk to the people that worked on this car in the SRT group and have amassed a huge amount of knowledge on this platform. I can confidently say that there are very few people that know more about this platform than I do. We abuse our car more in a month than most people will in the entire life of their car. I have no problem sharing what we have learned but it's people like you that cause people like me to not want to post on here. Are we a pro team with a million dollar budget? No, but I think the success we have at the track and the attention we get for having a Crossfire that pounds on Vetts and Porsches on their home turf speaks for itself. I don't know if you didn't get hugged enough as a kid or what exactly your problem is, but there is no reason to be a jackass constantly!

 

You made the generalized statement in the first post and now you expand on it and include some detail, I disagreed with your generalized statement, some of which was contradictory. I agree with most of this explanation.

Your current statement could be said to be somewhat contradictory, parts are replaced when they are deemed to have come to the end of their stress life based on calculations and field experience. No failure indicators may be seen, but it is only a matter of a little time and POOF it's done. Carrying on to failure can be fatal. The bigger the budget the more tests and the more new parts can be used. Losing an expensive piece of equipment for the cost of a part is false economy.

I am not an accountant or a laborer having worked in the engineering field for close to sixty years, so I do know of which I speak.

 

When I had my wavetrac installed - the installer was suprised I went for the 75/90 instead of the 80/140. I'd already bought it ($90 bucks here for 2Qrts) and changing the oil down the track is a real DIY so I was heading that way latr.

My Ring and pinion gear was worn and he made a point of telling me if there's a whine after install its due to that. He offered to take me for a drive pre-install to show that it was already there - but I took his word on it. He indicated it was evidence of a lot of highway driving at 55mph (previous owner).
The spiders were also slightly worn - but due to the wavetrac, the ring and pinion were the only ones replaced.
I still have the old spider gears downstairs in a box so if I can help with a photo - let me know.

He was also actually suprised how bad the OEM oil was after 80k miles when they drained it. I guess that's evidence that there's a lot of heat being generated in these babies at highway cycle.

b22b

 

http://i313.photobucket.com/albums/l...t/P1070894.jpg

Saw this pic. of a diff. cooler kit and wondered if anyone has done anything like this on one of our cars. I know that a couple of years ago Rob had asked Forum members if there was any interest; and there didn't seem to be any. He mentioned that he had parts all picked out for a kit for us. I think it was expected to be over $1K IIRC.

 

We will be designing and installing one in the race car in a few weeks and we will give all the specs and info to Rob. I can tell you that this diff tends to get extrememly hot. We are also installing a temp guage in the diff and will report the number with and without the cooler running.

 

When i did the wavetrac in mine, the car only had 8k miles, and i couldnt belive how bad the factory oil looked in the diff. And there was a bit of sludge in the case as well. Much more then i would expect for that low of milage. I guess age plays a part with that too. 7-8 yr old oil.

OEM should recomend a brake-in oil change for the diff after x# of miles or within the first year of new car ownership. IMO

 

Well, I listen to those who actually perform with their cars rather than speculate. I installed at 32k on the roadster, and 26K on the coupe. Everything looked OK, but we didn't mic anything, so who really knows. I haven't had any problems to date, but the coupe does have a little more noise than the roadster. I think a cooler, and a temp gauge is a good idea. We run them in the big rig on the both diffs. Gives you some warning on bearings and such, but wouldn't be any help with ring and pinion cracking. I can't fathom the temps being high enough for this problem to be happening. I think heat treatment or torque load is causing this to happen. Hopefully it is just happening to round trackers...lol....

 

I will be boxing up the rear and shipping it to the coast in a week, for gears, bearings, assembly and shot peening. When I get it back I will be looking at a way to add a cooler to it. I plan on chilling the case some with a water line tied to my super cooler. There is ample cooling capacity there and a low pressure line should not cause any issues. It will assist and I will be the first to agree it is not optimum, but I have been bringing creations forward like the oil separator, pulley saver, and S/cooler, even before there was a demonstrated need.

Should be possible to get some gain, and of course I will be instrumenting it for proof of the concept. Just have to finish the house and garage before the weather comes in, I hope.

Yall be well. Woody

 

Woody, I don't know how you do it....I remember working on this place 12 yrs ago. I couldn't nor wouldn't do it again.... I can't find time now to even work on the cars....let alone the house. Just lucky to keep up with the maintenance... Good luck to you, God's speed...