Morning,

Now...full transparency here. I'm a bit unfamiliar when it comes down to internal engine works here. About a month ago, I took it upon my idiotic self to mechanically over-rev my motor; roughly 1000 revs past the fuel cut off. To say the very least, I freaked! Granted it was only there for a split moment, it was there nonetheless - 8500 revs. I called quite a few people for opinions, insisted on a leak down test from my dealer, but all in all, I was told NOT to overreact, as having an issue would result in an immediate failed motor. A month later now, I'm hearing...or at least I think...some sort of slight, underlying clanking noise from the car; I've read all the s2k horror stories after mechanically over revving. It's not the valves fluttering, and I'm quite sure it wasn't there before. Here's the worst part, the noise has gotten ever so slightly more audible to my ears. I'm looking for thoughts and opinions as to what my next step should be. If it makes any difference, the engine is well maintained, as is the rest of the car. '13 6mt g37 coupe...was in 4th and went into 3rd, instead of 5th...while at the top of 4th. I've heard all the possible stories...clutch slipping, and the tach over shooting from such a quick rev, etc.

I've never heard of the vq37vhr blowing from being over revved, and I've heard that some of the vq race cars run high above the 7500 passenger car redline. Which is...some what reassuring.

Thanks,
Eric

 

If you missed shifted from the 7500 in 4th to 3rd you definitely went past 8500. But if a major problem didn't occur during that time you shouldn't worry. Our car dont use valve springs at least on the intake side which helps in terms of safety. But still, be careful next time.

 

I've been kicking myself ever since. First time over revving in the same manner...I was so dumbfounded by the entire situation lol

Thanks for the input man. I'm a little cloudy on your statement though - we still have valves...and the issue comes from piston to valve contact, right? After the whole mechanical over rev ordeal...?

 

Do some research on the VVEL mechanism its really interesting. Yes we still have valves, just that the valves on the intake side don't use the conventional spring that returns the valve to the closed position. Piston to valve contact happens when the valve spring does have enough force to bring the valve up in time due to how fast the engine is spinning. Thats why you upgrade valve springs on high revving engines so that the force exerted on the valve itself doesn't overcome the force of the spring.