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Old Apr 24, 2015 | 06:24 AM
  #101  
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Originally Posted by cole@ronzer.org
I would like one as well. Heading to Laguna Seca in late June and gotta pass sound
Several of you guys with the NPP are falling into the category this mod was originally started for - forcing the valves closed to meet tech requirements at Laguna Seca, etc.

I will know a bit more tomorrow regarding the valves with regard to CCM calibration. CarDaq comes in the morning, and I have 10 PCBs arriving tomorrow (nothing custom, so it'll be thru-hole proto boards), so it's going to be interesting.

Obviously, the retrofit crowd won't care much, but the factory-NPP owners may lose the ability to have the valves controlled by the CCM. While I have all of the circuits done, I've not physically cracked/Dremel'ed into a valve for the simple fact that they're $350 a pop.

Hoping one of you who wants/needs this is another EE. I have spoken to two others who are in the engineering field who have been working on this. I'm going to post everything I have in order to further tweak this concept. In lieu of trying to recover money (although the new spare NPP exhaust will be sold on here) from the project, which has grown into a monster, I'll just be encouraging people to donate to St. Jude's.

I pulled all of the pots out of all four circuits tonight and replaced them with fixed-value 1% metal film resistors. The less adjustment needed, the better. As it stands now, the last week has taken this more in a plug-and-play direction.

Keep in mind that this only affects and/or helps those of you that want to be in track mode and force the flaps closed, and retrofitters. Anyone else should be using the simple voltage switch to remotely control Fuse 41/42.

There's also the issue of increased backpressure - you'll be running hard with a very restrictive system with those flaps closed. It's far worse than the non-NPP system flow-wise with those closed down. Not trying to scare anyone, but in my case, running with the flaps closed at WOT would probably end very badly, very quickly. Just a word of caution, as I can't test those variables on a lab table.

Edit: Sorry for the typos and formatting - another very late night, and I need sleep...

Last edited by Theta; Apr 24, 2015 at 06:29 AM.
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Old Apr 24, 2015 | 08:21 AM
  #102  
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While Theta's work is in progress, my forte is temporary work arounds.
Ahhhh, another experiment. How many perforations can you put in the baffles, unplug the wiring so the baffles stay closed, and pass the required maximum sound level of Laguna Seca while suffering the least HP loss?
I like cheap options. Maybe unplug the fuse (or add the switch) so the baffles stay open, then fabricate a "clamp on" perforated tip for the exhaust outlet that is to be used on race day.
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Old Apr 27, 2015 | 05:03 AM
  #103  
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Would be a good idea if the baffles defaulted to closed, but alas, they default to open.

A user came up with an idea for a manual L-arm many months ago, but obviously there was room for improvement. I like your 'get-it-done' style, though!

Everybody ready to get excited? All done! Finishing the Multisim diagrams, and I've spent the day making a custom PCB layout and parts list.

No speaking, no music... Just letting the results speak for themselves until tomorrow. Well, technically later today, but my sleep schedule is ridiculous...

It's uploaded in 1080p60 (60fps) if you want to watch it on YouTube instead of this player.

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Old Apr 27, 2015 | 06:46 AM
  #104  
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Congrats.....a lot of people here are going to appreciate this.
GPM
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Old Apr 27, 2015 | 06:48 AM
  #105  
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Originally Posted by grandpawmoses
Congrats.....a lot of people here are going to appreciate this.
GPM
Thanks, my friend - means a lot. This project has really been something else. Another night of watching the sun rise, but designing the custom PCB sort of solidified the accomplishment after all the time and money spent on it.

Can't tell you how many projects just turn out to be busts, and this one had some pretty bad ups and downs. Now I can finally finish the first thread after starting the second - been at this for that long now.
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Old Apr 27, 2015 | 08:24 AM
  #106  
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Great job, Theta!
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Old Apr 27, 2015 | 09:10 AM
  #107  
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Oh man. Oh man. Oooohhhh man. Awesome work!!
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Old Apr 27, 2015 | 02:35 PM
  #108  
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This isn't a mod I'll need, but I'm impressed with what you've accomplished. I have a hobbyists knowledge of electronics, so I can follow what you've done, but no way could I have figured out how to do it.

Congrats! You have the right to be proud of your accomplishments.
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