The previously linked collars from Summit can be slipped on with one screw in place for sure as I did both sides that way, but can’t speak to the rest of the brands

 

That’s great, the ones I have will fit then. I might give his a try before installing the valve controller. Did you try a few positions, or did that one work first go?

 

Probably longer screws than the Amazon set I used. I think these things are holding on by two threads. lol

 

Just did the one position so far. Reading thru the thread it sounded like minimizing the travel (keeping mostly open) worked the best. It really is simple to do. I figure I’ll drive this week with it and hear it in lots of different situations before I going moving it around. I have the first autox next weekend and I can’t wait to hear it then.

 

Greg, still happy with this mode?

 

I ended up taking mine off entirely because I felt like there was just too much sound when I didn't want it. Granted, I had them up pretty far so the valves were almost wide open the whole time. I might dabble again with some settings but I like what I have with Akra OAP's as the stand alone mod. Now I just need to learn to live with that 4K RPM silliness, or possibly experiment with having the valves closed all the time and see if I like that. I probably won't.

 

In my experience, you should have started out exactly opposite: setting the collar low on the plunger so that the valves could be at least 80-90% closed most of the time. A small opening still lets out a lot of sound...think about how much extra sound a pin-hole leak in an exhaust will release (if you are old enough to remember the days when exhausts would more regularly rust out).

Obviously the best solution to this is a valve controller or a tune that gives you manual control of the exhaust valve. But don't give up on the collars just yet!

 

I agree with this. I first set them too open, and while there was no transition sound it just sounded open all the time and IMO that sound is not the greatest, kind of dumpy and raspy sounding. So I set them to only a bit open and the transition sound was still very subtle - it was an ideal setup for me with that exhaust. Day to day driving, because of the lower RPM meant you could not hear the open / close when driving around with the PSE on.

 

I'm going to experiment a bit. I agree with @UncleDude that the wide open sound at low speed/RPM is not great. The word I'd use is "tubby." Like the fart sound you make to emulate a '64 Bug. But my Amazon collars have an external diameter that creates contact with the actuator mounting nuts if I move the collars too far away from the valves. The collars need to be able to bottom out onto the actuator bracket (as opposed to the nuts) or they're not acting the way you want them to.

I'm trying to strike the perfect balance between obnoxious at low speed and that annoying 4K RPM transition. Doubtful I'll ever tune it or use a valve controller.

 

This is a topic I have previously tried to relate but have not been able to reason out.

Namely, I have my valves held open with collars. Everyone is different and, unlike yourself, I enjoy the valves open all the time.

The part I find difficult to reason is that, even with my valves fully open, there is still a very noticeable transition at the typical RPMs witness with completely OEM setup . . . as though there is still some degree of valve ‘opening.’ How is it possible to have ANY transition if the valves are held open?

Further, with valves held open, the acoustic output is completely the same whether I activate PSE or not.

Again, I cannot reason out this phenomenon, but it is real.
Avera

 

I'm with you. Something is happening to create that silly transition and holding the valves wide open doesn't seem to prevent it. I'd like to see what a decently tame, non-valved rear section would sound like. Enough of this computer controlled nonsense. Until someone figures out how to modulate the valves electronically instead of just control them to be ON or OFF like I understand the various controllers to operate.

 

@Avera
I was wondering the same thing, though I dont find it to be as pronounced during my daily drives as you do. AKRA OAP's + Collar Mod @ 95% open.

With that said, I decided to google 718 GT4 Dyno Charts... and the two I opened have spikes in the power bands right at 4K RPM (Vtech?!!). One graph showed the 718 stock, the other was tuned, both had a significant uptick in HP/TQ curves @ 4K.

 

The most uniform sound delivery I can get (with Kline) is valves closed. By the time the computer (or the pressure of the gasses) opens the valves it is already loud enough that you don't notice. I do agree something happens with the engine sound between 4000 and 5000 - collars won't fix that.

 

We are going to get outside my pay grade pretty quickly . . . but what you state makes sense.

HOWEVER, the 1st and 2nd gear 'opening' still occurs around 5K RPM and the 3rd-plus gear 'opening' still occurs around 4K RPM. Of note, I am not sure anyone who has PDK and drives in automatic mode would ever notice this phenomenon we are discussing with respect to having the valves held open. I spend 95% of my time in PDK manual mode so, like someone with a MT, all the intricacies are revealed.

I like what @SpyderSenseOC suggests . . . that there is some underlying computer control still at play. How? I have no idea because if the valves are open, they are open.

Avera

 

Well the engine is forced to cram all of its exhaust gases through a restrictive 1.5 inch exhaust below 4,000 rpms. Then all of a sudden less back pressure and a wide open pathway to the exhaust tips. I am sure there are major changes going on with the engine's ECU parameters right at that point as the car switches into another mode to build power to the redline. Those are likely the changes that you are noticing.