Subject	=( Damn, nutshelled into two sentences.
Posted by	Ash's Z on May 27, 2012 at 4:58 PM
	This message has been viewed 281 times.
In Reply To	Coles notes version: posted by MixManMash on May 27, 2012 at 09:08 AM
Message	;-) Answer to your question: yes, it could only have to do with the additional volume being that is all that is different. :) It makes plenty of sense, but so is hindsight. To have predicted it beforehand would have required a very complex analytical study. What I think is occurring with the larger pipes is due to the compressability of gases and how the larger volume has affected the frequency response of the pressure waves. It is analogous to a subwoofer cabinet, if you will.. A larger speaker cabinet with more air volume will have a lower resonant frequency as compared to a smaller cabinet. 1 explanation) The larger volume of air within upgraded pipes has lowered the frequency of the wave pressure resonance in such a way that has matched (or more closely matched) the mechanical response frequency of the modified GHK'd recircs.... There will always be a condition with BOVs where at the tail end of the blowoff event, it will create a oscillation of pressure within the charge pipe system. This is primarily due to the fact that BOV systems are not damped. The valve mechanism is controlled entirely with dynamic "sprung" forces; air is elastic, springs are elastic. Even the control diaphragms are elastic. There simply is nothing to dampen oscillations in pressure within the hard parts - the only reason the BOVs dont just continue to flutter is due to resistance losses - within its shaft-guide interface, frictional losses experienced by the air and the pipe walls, and the fact that the turbo is despooling and the system pressure decreases below the threshold of pressure energy required to raise the valve off its seat. The whole BOV system is like an array of interconnected springs and weights... In one of my responses to ConVerTT I mentioned how changing to a larger recirculation valve will likely eliminate the flutter as it will change the valve's mechanical frequency response in such a way that does not complement the pressure/wave response of the air within the charge pipe system. Enthusiasts soon understand each other. --W. Irving. Are you an enthusiast? If you are out to describe the truth, leave elegance to the tailor. Albert Einstein
Follow Ups	Can someone please explain the causes, effects and the best - DVDBURN (MD) 14:09:25 05/26/12 here... - KongZTT GT28RS MD 14:12:41 05/26/12 Too little flow for the pressure ratio. In order for the - Ash's Z 14:38:19 05/26/12 Thanks for the info. (n/m) - DVDBURN (MD) 14:52:12 05/26/12 Damn... Now my new Flutter Buster product is useless - LitlElvis 17:18:48 05/26/12 lol (n/m) - ZiNnYc 18:31:04 05/26/12 False. The flutter is really annoying in a convertible - ConVerTT 19:46:31 05/26/12 An active control system would work best. - Ash's Z 04:44:15 05/27/12 What about the flutter at the beginning of the blow off? - BlackholeZ 18:11:39 05/26/12 That would only occur if the BOV were malfunctioning. - Ash's Z 16:22:58 05/27/12 Couple questions - BlackholeZ 18:57:52 05/27/12 I did simplify the situation a good bit regarding the axial - Ash's Z 19:56:47 05/27/12 With respect, I am calling BS for two simple reasons: - ConVerTT 19:25:16 05/26/12 Original post with vids here Ash in case you missed it - ConVerTT 19:38:30 05/26/12 There is a huge difference in pressure and when the valve - LitlElvis 21:59:54 05/26/12 Ok, but do you accept my proposed test as valid? - ConVerTT 23:26:15 05/26/12 Sounds like a valid test to me. (n/m) - LitlElvis 10:26:34 05/27/12 but then you would get surge? (n/m) - BlackholeZ 19:00:33 05/27/12 Im actually elated that you bring this point. =) - Ash's Z 03:26:46 05/27/12 Coles notes version: - MixManMash 09:08:33 05/27/12 =( Damn, nutshelled into two sentences. - Ash's Z 16:58:00 05/27/12 Long paragraphs and bid words don't scare me :-) - ConVerTT 09:39:07 05/27/12 You will hear surge with no recircs. (n/m) - MixManMash 09:55:52 05/27/12 Yes. I want to compare the sounds. - ConVerTT 10:50:51 05/27/12 Re: Long paragraphs and bid words don't scare me :-) - Ash's Z 15:40:10 05/27/12 Thanks Ash and ConVerTT for the comprehensive discussion - OverZealous (CT) 15:31:24 05/28/12 My 2 cents....... - Greg D. (Specialty-Z) 10:06:29 05/28/12 That picture is ridiculous! (n/m) - na300zx (OH) 11:41:13 05/28/12 What were your suspension settings for this launch? (n/m) - KongZTT GT28RS MD 14:56:09 05/28/12 Awesome explanation Greg. - MixManMash 15:18:08 05/28/12 Good suggestion Greg. Great discussion all! - OverZealous (CT) 15:20:51 05/28/12 Honestly, I think the concerns for it are overrated... - ZinnZ32 16:24:18 05/26/12 My roomie's Turbo brick doesn't have a BOV - BlackholeZ 18:19:47 05/26/12
Post a Followup	You cannot reply to this message because you are not logged in.