100% agreed and if anyone thinks that the other tuners mentioned have not had catastrophic failures are living in a dream world. CMS is the only tuner I have ever seen that has put a failure out for all to see in an effort to inform for the good of all. I still say that pushing 900 HP or equal TQ equates to a ticking time bomb regardless of the tune unless you have replaced stock internals with properly rated parts and a good tune. To think otherwise is ludicrous - but what the hey - its not my money.

 

Photos look fine Tom but it would be best to establish the heat ranges the pistons were subjected to. That should determine a few things here. Do you have a hardness tester amongst your equipment?

 

As I'm sure you are aware of, the strength of the internal components of the motor are better defined in terms of torque, making it far more difficult to extrapolate the component's true exposure to torque due to the requirement of knowing the RPM at which the horsepower figures were reached. Many enthusiasts are unaware of this, therefore making statements such as tuner xyz was capable of reaching abc horsepower without knowing the entire story.

I think if you expand on this in another thread much of the misinformation and incorrect assumptions will be alleviated.

 

Tom,

I for one appreciate you sharing your experiences. Sorry to say what you are experiencing is along the lines of what I experienced back in 2004. Since then I volunteer a small amount of what I could and giggle to myself about many things I read.

 

CMS has been extraordinarily honest and open about their experience with their development engine. A very few other companies (AWE,Evolution) have had similar failures while in the pursuit of what the engine can be.

Childish comments removed...


This is what they do for a living. This is how they feed their children. This is how they entertain you. They could have chosen to be less transparent, less open. They chose the high road.

 

Good to know Paul. If my rods ever bend, I'll know who to consult regarding the cause which is still completely elusive here despite the interesting and spirited debate.

I'd like to hear a comment from CMS regarding the intial speculation by Tom in which he was convinced that the reason for the bent rods was trying to run 700+ whp on pump gas. If that's the case, what would cause the rods to bend, if not detonation? Is it the 68 mm vtgs gone wild? Those could generate a huge amount of tq down low. It's all anectodal, 600, 700, 800, etc...It's pretty obvious the higher you go, the more risk one assumes, what else can be concluded from this example? The "safe" number will always be subjective. The question still remains, what caused the rods to bend in this case? Idiopathic?

 

Subscribed! Thanks for CMS sharing with your honest finding and all others informaitve and valuable discussion!

 

Most interesting thread that I have read this year - thanks guys!

 

. For us nothing is idiopathic with an engine or component failure. Im not in the business of giving away free advice or service but when its a matter of my own personal interest it is FOC.

 

haha thanks cjv. Fortunately I am an extremely patient person, a gift I've learned to appreciate a lot recently.

TTdude....as I said much earlier on, we believe that the failure was due to the cylinder pressures created by generating over 700whp. I also never said pump gas specifically was the cause. Pump gas or race gas is irrelevant. BOTH our pump and race tunes operate safely free of knock with full control in place, again as I've mentioned 3 or 4 times. I'm not defining an absolute #, by any means. Yes, our 68mm turbos make a TON of tq down low, and they also make a TON of tq up top and good hp across the entire range. But isn't that what you want, the largest area under the curve possible?? Why tune a car with peak power that comes in for only a couple hundred rpm?? Why have 250 more peak hp then tq?? Our 68mm turbos don't "go wild" by any means. The fact is that they work...they make tremendous amounts of power across a VERY large portion of the rpm range. Could this be a contributing factor to why the rods bent at this power level while others don't? I suppose so....but the question once again becomes WHY? Why have such a large deviance between hp and tq? And why make a peak # at peak rpm? It just doesn't make for good driving car.

The fact of the matter is that the car is FAST with these turbos, even safely running 670awhp (which is the max we tune to without internals). In fact, a customer of ours in Turkey recently ran 5.5 60-130 with this exact kit at that power level. Faster then several cars equipped with GT or alpha turbos. Faster then all but a small handful of other cars. So my question is....in the real world...WHY need more power anyway, when roughly 650 to the wheels with VTG's gets you a USABLE power range that's faster then cars allegedly generating 200 peak hp more??? Riddle me that....

hmm, I'll have to check into that. To be honest, I don't think we have one, buy I'll have to double check. There are a few machines back there that....well...I'm not even sure what they do...LOL!

 

out of curiosity, What is your rev limit set to?

Additionally, has the ever experienced a mechanical overrev? (i.e. going into 3rd gear instead of 5th at WOT from 4th ?)

rod angle and weight of the rotating assembly are not a good mix

Justin

 

Tom, what is the peak torque achieved with your 68mm VTGs?

I would like to post my dyno runs for comparison but the format is not supported

 

Here is a dyno run with our 68's on a tiptronic 997. This is at the power level we are comfortable with. This is also identical to the car that ran 5.5 60-130. Actually, he's done a couple runs faster now, but hasn't sent the pbox info for verification yet.

You can email me your dyno runs if you'd like. I can convert them and post for you. Oh, and thanks for the comment in the TPC thread...that was very nice.

 

Email send

 

I highly doubt that the cylinder pressure in and of itself was the problem(600 ft lbs at 4k on a a Mustang dyno). My car was making in excess of 700rwhp on pump fuel for 8k miles with no ill effects. I believe on the Porsche engines that rpmXtorque is more of a problem than solely increased cylinder pressures at low rpm.

Justin