Thread: Pair Removal

You can get all of your Brocks parts from Cat3.

I try.

I did mine about 3 weeks ago,real simple,made a noticeable difference.BTW,got mine off Ebay for $12 and bought vaccum caps at o'reillys for about another $3,good $15 mod.

What exactly does this mod do? I hear guys talking about it but whats the gain/loss?

Weight loss, yes because you are removing parts.

the PAIR valve pulls CLEAN air FROM the airbox and injects it into the exhaust to reduce emissions.

the reason you should remove it with an aftermarket exhaust is because they all "pull" more air than stock which means it also pulls more unburned fuel. When this unburned fuel/air hits fresh air (with oxygen) injected by the PAIR system it can ignite causing nasty backfires. This tends to happen while letting off of the throttle and/or decellerating or at other points in the map where the bike will tend to be rich (ie: too much fuel/not enough oxygen to burn it all)

or

"The function of an air injection system is to prevent hydrocarbons from escaping into the atmosphere. In most engines, the intake valves open before the exhaust stroke is complete, and the exhaust valve are kept open past TDC. This is referred to as valve overlap. By keeping the exhaust valve open, the fresh intake 'charge' is drawn in and displaces what remains of the exhaust gases out the still-open exhaust valve. This fuel/air mixture 'charge' contains a high concentration of hydrocarbons (HC). The problem with this is that hydrocarbons can escape unburnt. By injecting fresh oxygen into the exhaust tract at the valve, the surrounding heat ignites and burns the remaining HC and reduces emissions."

So, the backfiring that we hear is the ignition of fuel that made it through the engine without being burnt.

Why does adding an exhaust cause backfiring?
Adding an exhaust leans the mixture for the above noted reasons. A lean mixture will not burn completely because the flame 'goes out' in the cylinder. Gas at the outer edges of the cylinder does not get burned, exits through the valve, and gets burned by the surrounding heat and the supplemented oxygen provided by the PAIR system.

I still need to post pics of the new Brock's system I got from CAT3.

I need to quit working so much. Overtime ownz me....

I will be installing my HMF full system (low mount duals) and need to address the P.A.I.R. valve issues...

I blocked them off and removed all related plumbing and valves on my '01 ZRX. I was thinking I would do this with the 'busa too, but heard about switching the airbox end of the line to draw pressure from the crankcase, supposedly decreasing pumping losses.

I have some questions:

Does this actually help power output? Any back-to-back dyno runs showing increase available?

Will the popping on decel that I've heard occurs when a full system is installed still occur if the valve is hooked up to the crankcase vent?

Will proper mixture adjustment for the pipe eliminate the popping if it does occur after this mod?

Will this damage anything in the long run?

I am thinking if it is worth less than two hp, I would rather remove the entire P.A.I.R. system; if there are documentable gains over two hp, I would probably do it.

Thanks,
Blue

Bad@*^! I'll order my exhaust from him when I get my 08