RS Warrior Forum banner

Aren't baffles supposed to HELP performance?

4.3K views 21 replies 21 participants last post by  eliminator68  
#1 ·
I've always been told that without baffles, there isn't enough backpressure and it hurts performance. Well the other day I decided to be myself and make a bunch of noise, so I pulled the baffles out of my street sweepers. Now, I've never made a dyno pull, but it seemed faster. I figured it was my imagination, with the increased noise and all. But on the highway, I got it up to 136, and it was still pulling, like with more road I might have squeezed out, dare I say, 140. With baffles, my best was 132, with MAYBE 1 or 2 left in it. I think I have the PCIII dialed in about as close its going to get, so what gives?
 
#3 ·
Just as Bladerunr said:
.) low and midrange torque: Yes they can help
.) top hps: baffles will hurt in most cases

In general baffles are there primarily for noise reduction and not for performance increase. If you check out the PR race bikes you will find very short exhaust with very little restrictions. In their case they even made them shorter in season two the further reduce low end torque as it helped with launching the bike with its 200 rear tire. They however make more than a LOT of torque [/emoticons/emotion-5.gif]. It gets wild with too much low end torque.
 
#7 ·
will having a BAK change the amount of backpressure (baffles) required for more torque? ie, assume the stock exhaust has the perfect backpressure for the stock air box, by adding a BAK, you won't need as much backpressure, having too much might negatively affect torque (assuming torque is your goal)?
 
#8 ·
Tiresmoke, I have the ripsaws, which are basically the same thing. I noticed this also. I think with the design(straight through) you will notice more on the top end, but the torque may suffer. But it is such a small difference that it is hardly notice on the bottom end. I had my baffles in just to quiet them down a bit, but took them back out the next day. I found I like it loud!!!!
 
#11 ·
Coulda made 140?
I have a DIY BAK and a Cobra slipon, and not much else.... and I hit the rev-limit at about ( an indicated) 134. So, mathematically speaking, that is all I'm going to get without changing something, like the ECU or drive ratio.
I have NEVER hit the rev limit on any other bike ( in HIGH gear). Usually ran out of horses first.
So: How did you defeat the rev limiter?
( and more on topic: )
I really Love my Cobra, now that I've repacked it with household insulation... nice note, and good power band...AND it can be quiet at 3AM.
 
#12 ·
It all has to do with valve overlap at low RPM. The baffles help to reduce the loss of power at low RPM by slowing down the air flow and preventing the fuel charge from being sucked out the exhaust port. The opposite happens at higher RPM because the valve events are much faster.
 
#13 ·
A well designed pipe with no-baffle can can make great low end power. It all depends on the design of the pipe. KT components made a two into one with a 2.5 inch collector athat made great low end poop even though it had essentially no baffle (just a perf stock plate).

Unfortunately I thisnk thay are out of business these days.
 
#14 ·
quote:Originally posted by The_editor

Coulda made 140?
I have a DIY BAK and a Cobra slipon, and not much else.... and I hit the rev-limit at about ( an indicated) 134. So, mathematically speaking, that is all I'm going to get without changing something, like the ECU or drive ratio.
I have NEVER hit the rev limit on any other bike ( in HIGH gear). Usually ran out of horses first.
So: How did you defeat the rev limiter?
( and more on topic: )
I really Love my Cobra, now that I've repacked it with household insulation... nice note, and good power band...AND it can be quiet at 3AM.


Thank you...I wondered that too...It's all physics. More power doesn't change the gear ratio.
 
#17 ·
Here is my experience with the Propipe on my 110" motor: I tried running with up to 6 extra holes in the stock baffle to reduce backpressure. Turns out that best power and torque across the whole range (after adjusting the PCIII map) was with NO extra holes in the stock baffle. Difference was at least 2 hp and 2 ft-lbs across the whole curve, after adjusting for best power each time. It should be noted that, contrary to popular assumption, reducing backpressure by adding more holes in the baffle actually richened up the A/F mixture, while adding backpressure leaned out the A/F ratio! Results may be different with drag pipes.
 
#21 ·
quote:Originally posted by Bunker

Here is my experience with the Propipe on my 110" motor: I tried running with up to 6 extra holes in the stock baffle to reduce backpressure. Turns out that best power and torque across the whole range (after adjusting the PCIII map) was with NO extra holes in the stock baffle. Difference was at least 2 hp and 2 ft-lbs across the whole curve, after adjusting for best power each time. It should be noted that, contrary to popular assumption, reducing backpressure by adding more holes in the baffle actually richened up the A/F mixture, while adding backpressure leaned out the A/F ratio! Results may be different with drag pipes.


Thanks for the info
 
#22 ·
[/emoticons/emotion-5.gif]I put the sweepers on my 05 a week after I bought it with no baffles and still had the AIS and no PC3. Ran Like *&^%$. Bought baffles, removed the AIS and ran better but seemed to run hot. Too much back pressure. Now with no baffles, no AIS, and custom PC3, I love it. Strong accell and noise racking Decell. The AIS choked it on the DECEll.
Ride it like ya stole it[8D]