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Discussion Starter · #1 ·
Doing a pair valve delete. Instead of capping off all 3 openings, what would happen if I just took off the valve and connected the hoses back together?
 

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It would be like an open valve all the time. Wouldn't hurt a thing unless your reed valves failed.
 

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Doing a pair valve delete. Instead of capping off all 3 openings, what would happen if I just took off the valve and connected the hoses back together?
It would be like an open valve all the time. Wouldn't hurt a thing unless your reed valves failed.
Wait, are you saying take off/out the reed valves under those plates?

The ONLY real advantage to disabling the system, is to reduce or get rid of the popping on decelleration when an aftermarket muffler is put on, or other similar exhaust mod. The popping isn't hurting anything actually, however I'm sure it would get annoying though.

You can simply disable it various low or no cost ways.
  • LIke plugging the hose to the air cleaner with a marble, or large bolt/screw.
  • or unhook the solenoid and connect a hose between the 2 pair valves.
  • T off the crankcase breather to the pair valves - best option- more HP

You can also take your crankcase breather and 'T' it off to the pair valves.- dyno proven HP gains- small one.
 

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Discussion Starter · #4 ·
It would be like an open valve all the time. Wouldn't hurt a thing unless your reed valves failed.
Ok good, now what would happen if the reed valves failed? And, how do you know if they are on their way out or have failed? Just curious because I'm fine doing it either way, but will go on the side of caution if one way is safer than the other.
 

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Discussion Starter · #5 ·
Wait, are you saying take off/out the reed valves under those plates?

The ONLY real advantage to disabling the system, is to reduce or get rid of the popping on decelleration when an aftermarket muffler is put on, or other similar exhaust mod. The popping isn't hurting anything actually, however I'm sure it would get annoying though.

You can simply disable it various low or no cost ways.
  • LIke plugging the hose to the air cleaner with a marble, or large bolt/screw.
  • or unhook the solenoid and connect a hose between the 2 pair valves.
  • T off the crankcase breather to the pair valves - best option- more HP

You can also take your crankcase breather and 'T' it off to the pair valves.- dyno proven HP gains- small one.
I'm going to be under there replacing my CCT, last time I had my pair out it was rusted inside, so I'm going to delete it completely, since I can turn it off in my ecu app. I was thinking of just getting a T adapter and connecting all the hoses together so they are completely open, instead of taking the hoses off and capping the two ports on top of the valve cover and the one at the air box. I heard that you gain a little HP that way as well.
 

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I'm going to be under there replacing my CCT, last time I had my pair out it was rusted inside, so I'm going to delete it completely, since I can turn it off in my ecu app. I was thinking of just getting a T adapter and connecting all the hoses together so they are completely open, instead of taking the hoses off and capping the two ports on top of the valve cover and the one at the air box. I heard that you gain a little HP that way as well.
If I understood you correctly, the only way you'll see any dyno differences is by creating a 'lower pressure' or vacuum in the crankcase- with the venturi like PAIR reed valves. Keep in mind, this system does not involve the combustion chamber. It's in the exhaust port only. Unless you're using it to create a vacuum in your crankcase like some have done, you won't see ANY gains by merely plugging it as the only change in the system.
I've read on some big V8's, with an accessory vaccum motor to the crankcase breather- as much as 30HP gained!
 

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Discussion Starter · #8 ·
Thanks guys
 

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It could bleed dirty exhaust gasses back to the airbox. You're actually just better off blocking the system

Now I'm not that well educated on 'when' the pair valve is in operation, but if it's working in all revs
it also decreases the effect of the ram-air since it creates an exit for overpressure
 

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If I understood you correctly, the only way you'll see any dyno differences is by creating a 'lower pressure' or vacuum in the crankcase- with the venturi like PAIR reed valves. Keep in mind, this system does not involve the combustion chamber. It's in the exhaust port only. Unless you're using it to create a vacuum in your crankcase like some have done, you won't see ANY gains by merely plugging it as the only change in the system.
I've read on some big V8's, with an accessory vaccum motor to the crankcase breather- as much as 30HP gained!
I've got friends who've gained as much as 80hp on big block race car engines, with vacuum pumps...but we're comparing apples to oranges.
Modern bike engines have far superior crankcase ventilation, compared to V-8's...20 years ago, we saw a move to the crankcase "windows".
Years ago, I also read about how the pair valve mods could net 1-3hp gain...ok, free hp...I'll bite...but saw nothing on the dyno.
Still not one to shy away, I bought a Fast by Gast 12 volt vacuum pump and mounted it on my Busa...back to the dyno, again, no difference off or on.
But nothing ventured, nothing gained...or I'd still be wondering what if? I have a shelve full of such things.
It may have merit with older GS or KZ drag bikes, they also run a venturi in their headers to suck out the crankcase...but I don't think there's any free hp to be had with a Pair mod.
Your results may vary.
 

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No sir,
The pair valve is not part of the intake system.
Well, it kind of is. The clean air input to the PAIR comes off the air box. But I don't know when the PAIR opens and closes. If it's only at idle, ram air isn't in play anyway.
 

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I've got friends who've gained as much as 80hp on big block race car engines, with vacuum pumps...but we're comparing apples to oranges.
Modern bike engines have far superior crankcase ventilation, compared to V-8's...20 years ago, we saw a move to the crankcase "windows".
Years ago, I also read about how the pair valve mods could net 1-3hp gain...ok, free hp...I'll bite...but saw nothing on the dyno.
Still not one to shy away, I bought a Fast by Gast 12 volt vacuum pump and mounted it on my Busa...back to the dyno, again, no difference off or on.
But nothing ventured, nothing gained...or I'd still be wondering what if? I have a shelve full of such things.
It may have merit with older GS or KZ drag bikes, they also run a venturi in their headers to suck out the crankcase...but I don't think there's any free hp to be had with a Pair mod.
Your results may vary.

Where did you hook the vacuum to? The crankcase breather to lower the crankcase pressure I hope.

A while back I did find this that shows a 'dyno-able' difference- when they simply piped the crankcase breather directly to the Pair reed valves. They saw a decent peak gain.



Well, it kind of is. The clean air input to the PAIR comes off the air box. But I don't know when the PAIR opens and closes. If it's only at idle, ram air isn't in play anyway.
I'm not a Suzuki Engineer, but the in stock PAIR valves- the 'SELENOID' only 'opens' the PAIR system at idle and low RPM's to help with idle emissions? The venturi in the exhaustr port is always working though, whether the solenoid is open or not.
For the Sucker mod- you completely disconnect the solenoid from the Pair valves.
 

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The service manual indicates that the valve used on my K6 1000 is normally open and closes when energized. SDS shows the state of the PAIR system. Years ago I put it on a portable system in a backpack and logged things on a ride. I plotted the results and posted here but the images were on Tinypic and now gone. One was reposted:

PAIR is near the bottom. It shows the PAIR system is normally on and closes briefly during shifts and above about 4500 RPM. That solenoid is used in many other applications so I assume they all work about the same.

IMO you're best off to remove the system and install blockoffs as it dramatically cleans up the top of the engine. But you need to either leave the solenoid connected to the harness or install a resistor in its place, as has been discussed here before. The reed valves can pick up carbon deposits but breakage failure seems unlikely.
 

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Looks like it opens when it detects a negative delta in the IAP. Basically on decel. But you throttle position confuses me around the 360 second mark. One closed, one open and both indicate a drop in pressure, but he PAIR is open the whole time.
 
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