Competition What happens when you make more power than your drivetrain can tollerate.

[Turbo Thom]

Funny ain't the word for it. That damn halo is going to choke him... ... ... ... ... ...

 

[NIsaacs]

I am just a little guy when it comes to the power you big boys make. However even with the small power I am used to, one big difference between gas and diesel power is rear axle ratio. The high rpm of the gasser = torque multiplied by low gears in the rear axle = light drive line/u-joints. The low rpm power of the diesel = higher rear axle gears = power produced before the rear axle = heavy duty drive line/u-joints.



Based on the original post and pictures, I would say the u-joints were too small for the power produced before the rear axle.





"NICK"

 

[RacinDuallie]

Greg, why are you always picking on me? I'm just trying to help.

Could this be the proverbial 'olive branch'???

Does the Tinman really have a heart?:-laf :-laf :-laf
Does the Scarecrow get his brain?:-laf :-laf :-laf








All this time and I thought that movie was a bunch of bunk!

 

[COMP461]

Pro Mod car are running gear ratio's in the range of 3. 55 diesels are running in the range of 2. 90 or less , but remember these gears are recycled A/FD gear , and if the rules would let them would run gears in the neighborhood of 2. 50 . Still the typical Blown Pro Mod run twice the torque as any 5. 9 Cummins is putting out to the track; remember that in drag racing, no one going fast even gets close to the torque peak, but runs up in the RPM band.

 

[Amish Elegance]

This damage is no doubt to suspension misalignment , but Ill quit trying to educate people an let them break things , I just want set by and watch some one get hurt . sleddie you have nothing better to do then try and hijack ever post that I lend knowledge to , I have a lot of experience in chassis drag racing , and with motors that would dwarf your so called pulling diesels in the torque department , but you keep entertaining people with you non knowledge post , and attack on any one that knows any thing . And I’ll keep writing the truth, unless you have some legitimacy, Sleddie care to lend you omnipotent knowledge to extrapolate the cause of this potential catastrophic failure of a drive line component. A failure like this might get some one killed, or a bystander injure. But you infinite knowledge of the basic of drag racing should help solve this dilemma.



Just because is measures right , there are many more factors to conceder in figuring pinion angle , and the proper negative pinion angle to put in play to assure that everything is right when the load is applied ,and everything is tweaked .



I did try to help, even offering the help my chassis expert, and team mate Charlie Stewart who’s many years of Pro Mod experience, took 30 seconds after looking at the picture to tell me the problem and the solution, and offered to explain the method to setting pinion angle

I re-read this thread again, and I have yet to see where you offer any help other than sitting back and sayin somethings wrong. How about instead of just making comments in an attempt to put yourself on a higher position than us common folk, you offer some creative suggestions that actually help. No more, " I tried to help you, but you diesel guys just dont get it. "





This condition aside...

What factors should one look at when setting up a rear end?

Besides aligning things by the book, what has your experience been with other factors that may not be apparent? What else to look for?

What is the maximum angle that a U joint can operate at under those loads?

What Joint do you recommend?

How do you judge rigidity of your setup and its reaction to the power and achieve desired negative pinion angle?

Some of these things will vary track to track, but honestly, I'd love to hear about what you've experienced. No jabs intended. Sort of a 200 level course if you please.

Expect some debate, but thats how people get smarter.

Now in this instance... what, in your opinion, exactly went wrong, and what are the corrective measures?

Preston, let us know how close he gets.



FYI. As soon as I find a candidate, I'm going to be doing a school of hard knocks build up on a 2nd gen myself. Back half, cage and all. The 03 becomes the hauler. Prolly never get past two didgets in front of the dot, but it'll be fun. Who knows. I write my own checks, so the progress will be slow, but in the end I'll be smarter, happier, and a whole lot poorer. :-laf Answers to these questions would benefit myself as well as others.

 

[sbentz]

Guys, it's simple. Too small of a u-joint. Step it up. No more sissy gasser parts, go for the real stuff. Here's the one we use in the dragster:

 

[bgilbert]

diesels are running in the range of 2. 90 or less .

Silly gasser :-laf . .

 

[LPreston]

Guys, it's simple. Too small of a u-joint. Step it up. No more sissy gasser parts, go for the real stuff. Here's the one we use in the dragster:

2 please... .



Am I going to have to wear the funky 80's outfits to install them?

 

[LPreston]

Just because is measures right , there are many more factors to conceder in figuring pinion angle , and the proper negative pinion angle to put in play to assure that everything is right when the load is applied ,and everything is tweaked .



I did try to help, even offering the help my chassis expert, and team mate Charlie Stewart who’s many years of Pro Mod experience, took 30 seconds after looking at the picture to tell me the problem and the solution, and offered to explain the method to setting pinion angle

Greg,



If the angle was the issue, why have we been able to run 2 seasons (almost EVERY weekend) with not a problem? The only 2 times we have had yoke failures is when Keating "cranked it up a notch" at the line. Are we exceeding the capability of the parts at that point? Does it exceed the "load" capacity of the chassis? It just seems to me if it were pinion angle, we would have constant failures which is just not the case.



Keating has a great resource here in Knoxville with a Pro Mod crew chief who has been all over the truck and has seen it run numerous times and I believe has reviewed the pinion angle and 4 link setup.

 

[RacinDuallie]

I am wondering what diameter your 4 link bars are and what material are they made of? I also wonder if you guys could be experiencing some flex within the bars themselves?... ... ... .
Are the bars also equal side to side?

Doesn't somebody made a hi-grade billet joint?

 

[GIT-R-DONE]

I did try to help, even offering the help my chassis expert, and team mate Charlie Stewart who’s many years of Pro Mod experience, took 30 seconds after looking at the picture to tell me the problem and the solution, and offered to explain the method to setting pinion angle

For some reason, I'll bet Keating already knows how to set that up properly...

 

[Timbeaux38]

2 please... .



Am I going to have to wear the funky 80's outfits to install them?

no, but you do have to grow a mustache like those guys to get it right... :-laf

 

[LPreston]

no, but you do have to grow a mustache like those guys to get it right... :-laf

I'd rather wear the clothes... .

 

[LPreston]

no, but you do have to grow a mustache like those guys to get it right... :-laf

The more I go back and look at the photo, I keep hearing this bad "actor" in the back of my head ask, "Did somebody order a u-joint?" accompanied by cheap "bow-chick-a-bow-bow" music.

 

[JoshPeters]

The more I go back and look at the photo, I keep hearing this bad "actor" in the back of my head ask, "Did somebody order a u-joint?" accompanied by cheap "bow-chick-a-bow-bow" music.

And in walk Sleddy and Comp... ... ... .



:-laf :-laf

 

[Cooker]

The more I go back and look at the photo, I keep hearing this bad "actor" in the back of my head ask, "Did somebody order a u-joint?" accompanied by cheap "bow-chick-a-bow-bow" music.

I can hear the music now :-laf :-laf

 

[biggy238]

remember that in drag racing, no one going fast even gets close to the torque peak, but runs up in the RPM band.

Which in itself is why racing power and sled pulling power are not comparable??



I do have a non rhetorical question. . Why is the keating truck only running at 1. 17:1 TQ:HP ratio. . Is it the engine build?? Cam profile and desired HP peak?

I just hadn't considered the notion that most street and pulling trucks dyno in the order of 2. 2:1.....

 

[COMP461]

Here it is simple; torque is a component of horse power,

Horse power is the real and only measure of how much power you have.



If you have hp you can make any amount of torque you want with gears



Example if you have 1000 hp at the flywheel, you have the same hp at the tire less parasitic drag , parasitic drag , as in the Dana 80 has about 10 times the drag or a good 9. 5 ford low drag gear set.



1000 hp low rpm diesel 2800 rpm’s = 1875 FPT ???? Want turn fast enough to drag race with out over drive



1000 hp high rpm diesel 4200 rpm’s = 1250 FPT 2. 40 1st gear x 2, 70 rear gear = 8100 FPT @ 648 RPM’s at the tire 648RPM’s x 8100 / 5252 = 1000 hp



1000 hp high rpm gas 8000 rpms = 656 FPT 3. 45 1st gear x 5. 23 rear gear = 11,836 FPT @ 443 RPM’s at the tire 443 RPM’s x 11,836 / 5252 = 1000 hp



Horse power = torque x RPM’s / 5252

Torque = hp x 5252 / RPM’s





Three motor all making 1000 hp the one that will rev up ad accelerate will always be faster, that is undisputed fact. The only way to make power is the combine fuel with oxygen, and the limiting factor is oxygen, Air changes in the motor is all that maters. The more air changes the more fuel you can make power with. This is achieved with cams cylinder heads and more efficient use of turbo chargers, more boost doesn’t all ways yield more air , the law of diminishing returns is in effect here , more boost only tries to squeezes air thru a small port and make heat and sonic chock.

 

[Turbo Thom]

OK... ... ... ... Lay off the facial hair and attire. I don't see a thing with either one. Just two hard working driveline techs.



. . PrestonL. .

 

[biggy238]

Go sled pull for a while and see what happens greg...