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-   -   GTM Performance Engineering: VQ37VHR Engine Build 700HP Power Package (http://www.the370z.com/forced-induction/55629-gtm-performance-engineering-vq37vhr-engine-build-700hp-power-package.html)

phelan 06-05-2012 02:41 PM

Quote:

Originally Posted by Mike@GTM (Post 1755198)
We've given you all the details.

I will say that there was no evidence of detonation: the valves weren't burnt, the pistons weren't melted or pitted. Granted, only the owner of the car knows what happened and we aren't necessarily privy to that information in the first place. Also, you need to remember that not every car owner really knows what is going on under the hood or what they did to cause a catastrophy. I've seen many a "deer in the headlights" looks from people with broken stuff. They just don't know and simply aren't able to understand that by doing X, Y can happen. By them not knowing, they have no way of communicating relevant information. I can't tell you how many times I've heard "I was just driving along normally, and suddenly it just blew up". They usually forget that the night before when they were ripping on it with reckless abandon something subtle happened that they didn't notice and the next day the nature of the true damage reared its ugly head when they were casually taking off from a stoplight and they're like "OMGWTFBBQ just happened!?!?...I didn't even do anything!!!".

Ultimately, there is always a level of uncertainty when modifying cars. The bottom line with this particular failure is that we've given you guys all the facts and you must draw your own conclusions as to the cause...not that you'd listen to us anyway as evidenced by some people's posts.

Also, there was no Nitrous Oxide involved or signs that it was ever installed. If there had been, don't you think we would have mentioned it?

Angry much, Mike? lol

Well...probably as good an excuse as any to build something nice. It's a wreck going into GTM, let's see how it comes out.

Cmike2780 06-05-2012 03:14 PM

I think everyone here were just curious as to what exactly happened, considering there are quite a few people on here with roughly the same mods. Knowing you guys at GTM are pro's at this, we just thought you would know more about the circumstance leading to the engine grenading.

valpozguy 06-05-2012 03:15 PM

Quote:

Originally Posted by Cmike2780 (Post 1755422)
I think everyone here were just curious as to what exactly happened, considering there are quite a few people on here with roughly the same mods. Knowing you guys at GTM are pro's at this, we just thought you would know more about the circumstance leading to the engine grenading.

Agreed

sent from my SAMSUNG SINGLE TURBO SGH1717

theDreamer 06-05-2012 03:17 PM

I think there are to many variables to know exactly what happened, and I can easily see GTM not wanting or needing to know what the owner was doing when it happened or if the owner even knew. Guy could have been at the track two days before and when driving to work it blew.
Could have been all the bolt ons, driving it hard and the tune was just bad.

Mike@GTM 06-05-2012 03:23 PM

Quote:

Originally Posted by phelan (Post 1755368)
Angry much, Mike? lol

Well...probably as good an excuse as any to build something nice. It's a wreck going into GTM, let's see how it comes out.

Haha...not really.

It's actually funny, but the guys on the G37 forum seem to get it. But, that's what happens when you've got a physicist who understands harmonics on that board.

Quote:

Originally Posted by Xracer (Post 3460455)
Wow that is some serious damage, the flywheel bolts completely sheared off? That is some serious force. Its hard to tell from the pictures, but at a glance it actually doesnt look like pre-ignition is the cause for this. Generally with engines that fail from pre-ignition, they show evidence of the phenomenon prior to the actual failure. At the same time the cylinder pressures sky rocket, the temperatures do so as well. The shock and heat literally degrade and melt corners or sharper edges of the aluminium pistons and head. One thing to consider is the torsional vibration or resonance characteristics resulting from the Stillen pulley.

Although a billet pulley is good for reducing rotating inertia, I am a strong believer that they only belong on accessories ( AC, PS etc..) This can get pretty involved physics, wise but in a nut shell, your engine's rotating assembly behaves much in the way that your suspension does. Your car's suspension takes a step input (a bump in the road), the spring stores some of the energy, and the damper dissipates it. This spring-mass-damper system is just like an engine's combustion (the bump in the road), pistons-rods-crank (spring and mass)...but where is the damper?! Most OEM Crank pulleys are not solid metal through and through actually. Most have rubber embedded in them or a viscous fluid. The rubber or fluid is the damper.

This may sound far fetched but you'd be surprised what can happen when the rotating assembly in an engine experiences resonance. It could very well end up looking like that poor engine. In any spring-mass-damper system, if you chance one of the components, you change the response of the system to any input. And hey, these engines operate over a frequency range from 0 to 7500rpm... plenty of room for strange things to happen.

Anyways, absolutely nothing against stillen or anything. Just thought i'd bring awareness to the subject. Lack of tuning/knock is the most common reason for engine failure like that.


Mike@GTM 06-05-2012 03:28 PM

Quote:

Originally Posted by theDreamer (Post 1755426)
I think there are to many variables to know exactly what happened...

For the most part, this is true. Sometimes, one thing by itself may not cause a major issue, but when you start throwing other things into the mix, the combination can result in a serious problem.

efuseakay 06-05-2012 03:39 PM

Quote:

Originally Posted by SS_Firehawk (Post 1753020)
Believe me, there is no way the pulley did that. It would be instantly noticeable the instant you crank your car if your pulley is having detrimental effects. A 1/8in piece of rubber is not going to be the difference between a perfectly fine motor and a destroyed one.

This looks more like over revving with bad AFR's and detonating. Causing combustion too early in the stroke can and will cause catastrophic failure. Google and educate yourself.

At least the car isn't getting scrapped, GTM FTW... And the owners wallet.


Oh, for sure... I doubt the likely vibrations from that pulley helped keep things in tact though... We will never know what AFR that engine was getting... obviously... lol

gbrettin 06-05-2012 04:13 PM

Quote:

Originally Posted by theDreamer (Post 1755313)
Well with the TT kit they don't need them, so up to the owner if he wants to sell them.

Exactly my thoughts.

---

Meh, better not even think about those LTH. I have bigger and better things in the plans for next year.

Jordo! 06-05-2012 06:04 PM

I'm guessing oil pump failure... gee, wonder what caused that...

blackonorange 06-05-2012 06:59 PM

Scary stuff in here

Flyboy 06-06-2012 04:00 PM

Quote:

Originally Posted by Jordo! (Post 1755689)
I'm guessing oil pump failure... gee, wonder what caused that...

I agree with that. Probably oil pump, or excess water in the Gas.

Either way, I wouldn't use any of the old parts and put new gas in the car.

Jordo! 06-06-2012 06:01 PM

Quote:

Originally Posted by Jordo! (Post 1755689)
I'm guessing oil pump failure... gee, wonder what caused that...

http://i313.photobucket.com/albums/l...E/P1170880.jpg
Hmm.

370Z Purist 06-06-2012 11:20 PM

subbed for build progress, more pictures, 700 horsepower, and tons more conjecture on what made the engine turn into a bomb

sparky 06-25-2012 08:15 PM

Is this thread dead? Was sub'd for updates!

conmam 09-06-2012 02:19 AM

Quote:

Originally Posted by Jordo! (Post 1757715)

I I have to agree that replacing the factory harmonic balancer with an aftermarket lighter pulley will pose an incredible risk of killing your engine.

We are talking about a total engine eradication just like what you saw on the photos that Sam posted. This looks so much like what happened to my friend 9 years ago on his BMW 328 with the E36 motor series ( Inline 6 in this case ).

As we all know, the popular method for making power pulleys on E36 engines is by removing the harmonic damper and replacing it with an underdrive lightweight alloy assembly. This is a VERY dangerous product because this stock damper is essential to the longevity of an engine. The substitution of this part often results in severe engine damage.
It is also important to understand that while the engine in a BMW is designed by a team of qualified engineers who understood the engine characteristics inside and out, these aftermarket power pulleys are created by the people who do not understand many of the very important principles of physics.

To put things simple, it is not the underdrive feature that kills the engine, but rather the lack of dampening the harmonic vibration that the crankshaft generates every time after each cylinder firing sequence. When this sinusoidal harmonic vibration coincide with the phase vector of the engine RPM, resonance frequency will occur. When this occurs, it must be counterbalance immediately and that is the exact job of the harmonic balancer pulley. If not, the power under the sine curve will keep on increasing or accumulate exponentially and that will guarantee to destroy the entire engine and the possible surroundings, such as the starter in this case of this VQ37VHR engine.......

Think 5 times BEFORE you put in an underdrive aftermarket pulley. The risk is 1000 times the reward.... Not worth it at all......


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