VVT Tuning Noise - ADDED: Comparison Video

[DriftHappens]

see here:

http://www.ft86club.com/forums/showthread.php?t=47263

[86-tundra]

also you can hear it in this video

[ame="https://www.youtube.com/watch?v=bw_f3ZS78vk#t=36"]SCION FR-S OPENFLASH Header - YouTube[/ame]

[SirBrass]

Originally Posted by Tromatic

OP needs to a bit more direct in accusing Shiv of being a BS artist.

I wouldn't say shiv is a BS artist. His stuff does as advertised & he's a good tuner. It's just not the be-all end-all solution it's marketed to be. On par with other unlocked tuning solutions but easier? Sure.

He's a good marketer is all. Not a bs artist.

On phone I am. Therefore, if mistakes I make, Frank Oz blame you should.

[regal]

I here it exactly 4-5k and my car is stock. I've read removing the sound tube gets rid off it. I'm used to it by now.Also real 0w20 oil reduces the noise.

[SkullWorks]

I first noticed the noise when MPT was dialing in the engine on AEM series 2 (sans DI) the noise is almost assuredly the cam phazers themselves, they work using the ratcheting effect of the valve spring resistance against the cam rotation, decreasing the rate of change in cam angle decreases the noise drastically.

If you pay alot of attention you can hear this even on a stock tune, it is just not as prominent because the rate of change is much less, there is probably some amount of delta the factory allowed between rpm or load breakpoints.

If you ask the cams to go from full retard to full advance (or visca versa) in one break point it goes crazy for a couple hundred RPM trying to get your desired angle.

Other systems make less noise because they require the oil pump to move the cams, or rely on different technology entirely. there are benefits to this type of phazer, this is the drawback.

[SirBrass]

Originally Posted by regal

I here it exactly 4-5k and my car is stock. I've read removing the sound tube gets rid off it. I'm used to it by now.Also real 0w20 oil reduces the noise.

I have my sound tube, and while I removed it before I got tuned, I suspect that the noise would've been greater than it is now. But, it's still there even without the tube (and the cabin hole is plugged by a sealed gromet through which my 5ch amp's power line is run through). However, I hasten to reemphasize that the sound is not annoying. It's just noticable as the sound changes from normal "hrmmmm" sound of the engine intake + exhaust at street and cruising revs, to more of a "brrrrrwahhhhh!" as it moves between 3200 and 4k, then keeps that sound, but quiets down above 4k (in terms of intake noise), while exhaust volume increases with the revs.

It doesn't sound sick or bad or anything, just different.

[Deathreaper]

Originally Posted by SkullWorks

I first noticed the noise when MPT was dialing
Other systems make less noise because they require the oil pump to move the cams, or rely on different technology entirely. there are benefits to this type of phazer, this is the drawback.

Could this damage or cause significant pre-mature wear and tear in the long run?

[Dezoris]

Well I am not calling out anyone. I asked, Shiv and Perrin, neither can answer the mechanical cause for the noise.

What this means to me is they are are focused on the the cause and effects of changing the cam angles on the dyno. The fact that they don't have an answer as to why the changes they made introduces "valvetrain" noise immediately rules out continuing to run the tune in the current state regardless of if it makes more power or not.

[Element Tuning]

More than likely people are describing different noises that are all timed around the heavy advance of the intake cam. The intake cam phasing and the direct injection pump phasing go hand and hand. Tuning the cam aggressively can gain some power down there and it does make intake resonances but on some cars you can get the "marbles" or almost "knocking" sounds. When I had to work out the DI pump targets, duty cycles, phasing, dump valve, etc with the Hydra EMS I could induce significant DI pump noise. Careful tuning and asking only what the pump could deliver is critical!

Now the reason some get this "marble" sound and other's don't could be tied into how well the DI pump is working. Pulling back on intake cam advance can silence this sound but its just a sign the car may have a faulty DI pump.

Two different sounds, one normal, and one is bad!

Thanks,
Phil Grabow

[evo4g63]

Originally Posted by DJCarbine

Sounds like an exhaust leak almost around 3500-4000RPM right? Like a metallic rattle..... Stock tune doesn't do it, its gotta be the exhaust note due to aggressive cam phasing. Could be why there is a torque dip in the first place, people would complain of the engine note and think something is wrong.

Just my theory of course

I have heard what you describe since re tuning my car on the new header. Sounds like an exhaust leak to me but checked everything mechanical wise and nothing.

[DAEMANO]

[wparsons]

Originally Posted by Dezoris

Well I am not calling out anyone. I asked, Shiv and Perrin, neither can answer the mechanical cause for the noise.

What this means to me is they are are focused on the the cause and effects of changing the cam angles on the dyno. The fact that they don't have an answer as to why the changes they made introduces "valvetrain" noise immediately rules out continuing to run the tune in the current state regardless of if it makes more power or not.

So basically you're accusing them of causing an issue with no proof other than you don't like the noise? Have you not read the posts from people stating they get the noise on the stock tune if you listen carefully?

I'd read the quoted post below, flash back to stock, fill up with crappy e10 or e15 gas and go to the dealership complaining about the cricket noise to see if they'll do the DI pump TSB for you. Then see if you still have the same noise, or if it's a different one. Mine definitely doesn't sound like marbles or anything harsh, just a raspy resonance in the intake. The videos you posted don't sound like marbles or knocking either?

Originally Posted by Element Tuning

More than likely people are describing different noises that are all timed around the heavy advance of the intake cam. The intake cam phasing and the direct injection pump phasing go hand and hand. Tuning the cam aggressively can gain some power down there and it does make intake resonances but on some cars you can get the "marbles" or almost "knocking" sounds. When I had to work out the DI pump targets, duty cycles, phasing, dump valve, etc with the Hydra EMS I could induce significant DI pump noise. Careful tuning and asking only what the pump could deliver is critical!

Now the reason some get this "marble" sound and other's don't could be tied into how well the DI pump is working. Pulling back on intake cam advance can silence this sound but its just a sign the car may have a faulty DI pump.

Two different sounds, one normal, and one is bad!

Thanks,
Phil Grabow

That's some good info. I get some noise on mine, but it's not a harsh marble sounding noise, just a minor rasp.

Mine has also always made a different noise (almost sounds like a tractor) at very low RPM's, but it's very brief and every other manual car I've driven makes the same noise.

[regal]

@Dezoris, try losing that heavy weight 0w20 redline oil. Guinuine Toyota Motor Oil would be worth a try and not to hard on the wallet.


I think expecting an answer to a complex tuning "symptom" out of those too mentioned is a stretch, Delicious has been tinkering on Subaru's forever.

[arghx7]

So far there's nothing to indicate that there's anything wrong with the engine from alleged AVCS noises. If Subaru had put a ton of extra sound deadening and noise cancellation crap under the hood, everybody would be complaining about the extra weight and clutter, removing it anyway.

Originally Posted by SkullWorks

I first noticed the noise when MPT was dialing in the engine on AEM series 2 (sans DI) the noise is almost assuredly the cam phazers themselves, they work using the ratcheting effect of the valve spring resistance against the cam rotation, decreasing the rate of change in cam angle decreases the noise drastically.

If you pay alot of attention you can hear this even on a stock tune, it is just not as prominent because the rate of change is much less, there is probably some amount of delta the factory allowed between rpm or load breakpoints.

If you ask the cams to go from full retard to full advance (or visca versa) in one break point it goes crazy for a couple hundred RPM trying to get your desired angle.

Other systems make less noise because they require the oil pump to move the cams, or rely on different technology entirely. there are benefits to this type of phazer, this is the drawback.

Sorry, do you have a source on this? I was under the impression that the FA20 used conventional phasers (advance and retard chambers using hydraulic pressure). What you are describing sounds a lot like the cam-torque activated system found in Ford and Jaguar products and originally developed by Borg Warner.