Post by 90GTVert on May 7, 2012 8:06:22 GMT -5
Phase 4 Summary And Conclusions
I've tried all of the pipes, other than the MRP that caused engine damage in Phase 2, once again, but with a larger carburetor and intake setup this time around. I think the results more accurately show each pipes abilities in this phase than they did in phase 2, so let me start off by going back over some of the info acquired. Refer back to individual tests for full details on each exhaust.
*Prices may vary depending on seller and shipping charges. All prices assume no installation fees and account for no additional parts.*
Main Jet Changes
Exhaust Sound Level Comparison
Since a big part of an exhaust system's job is to keep things quiet, I wanted to test a few pipes to see just how well they do that job. I tested the stock exhaust, Leo Vince GP, Leo Vince ZX, Peace Pipe, and the Phongeer exhaust. You may have noticed that I left out the Leo Vince SP3, the 50-70cc ZX, and the YMS V8. The two ZX pipes sound the same. The street style exhausts were all so similar in sound that I opted to exclude the SP3 and V8 to save time and gaskets.
I used an SPL meter to give results in decibels (dB) at idle, 5,000RPM, and WOT. The meter was placed 6ft from the corner of the rear tire on the exhaust side at roughly a 45 degree angle. I felt this method would be most fair since some pipes had a side outlet and others had a rear outlet. I marked all locations with masking tape so I could be certain that results stayed fair for every pipe. I used a stock airbox to keep the modified airbox from having an effect on dB levels.
www.youtube.com/watch?v=BszoxG7W1RA
As I mentioned in the baseline for this phase, the stock pipe is has something loose inside of it that rattles around. I haven't noticed a change in sound, but I can't swear that it's exactly the same as always. I can't imagine that it's very far off of where it should be, if off at all.
All of the street style pipes did an excellent job of keeping the engine quiet. Once past idle, they are right on par with the stock exhaust. The Phongeer even did a better job of quieting the engine at high RPM than stock. I was surprised to see the Leo Vince ZX keeping up with the quiet street pipes. The Peace Pipe was the standout of the group with much higher readings.
For anyone not used to looking at dB readings, there are a few things to note here. Sound pressure level does not always accurately reflect perceived loudness. SPL is an objective measure, while loudness is a subjective measure as perceived by a human. It is said that an increase of 10dB is roughly equal to double the perceived loudness. Human hearing is also more sensitive to certain frequencies, so different exhaust notes can be perceived as louder even at the same sound pressure level.
Technical mumbo jumbo aside, the Peace Pipe is LOUD. It's loud enough that I suggest a full face helmet and/or ear protection on long rides. It could cause hearing damage depending how long you are exposed to it. Otherwise, the pipes aren't bad. Even though the ZX shows similar dB readings as the street pipes, it is louder in the real world. I think a few factors are at work there. One is the tone of the pipe, perhaps it falls into a more sensitive area of hearing. Another, which I feel is the major contributor, is the location of it's outlet. Pipes that exit to the side tend to sound louder than the ones with a rear exit while you ride. Lastly, the ZX operates at a higher RPM than the street pipes and volume increases with RPM. The stock and street exhausts are mostly staying in the neighborhood of 8,500RPM at WOT, while the ZX pushes above 9,000RPM. The Peace Pipe takes it even farther wanting to go to 10,000RPM or beyond with the right setup. On the stand for the test they all revved out close to 10,000RPM under no load.
To make a long story short, any of the pipes I have tested aside from the Peace Pipe should be OK on the street as far as volume is concerned. With the street style pipes you can tell a difference in the sound, but it's not huge. The ZX is actually louder, but it's still not something that should get you into trouble based on sound. The Peace Pipe will draw a lot of attention and is very loud to ride with.
Conclusions
The first thing I've seen here is that a larger than stock carburetor and intake track is very beneficial to a piped 90+cc engine. Not only does it increase performance, but it keeps the engine cooler. In the case of the Peace Pipe, the stock carburetor wasn't even capable of keeping heat down enough that the scooter was able to be ridden for very long. Lower temps are easier on parts and could help to extend engine life.
It became much more apparent this time that choosing a pipe intended for your displacement is important. Even if the pipe for a 50-70cc is designed in a manner that doesn't damage the engine, it's not designed to handle the larger volume as well as the 90-100cc specific exhausts. Every 90-100cc pipe outperformed every 50-70cc pipe. The fact that some of the big engine pipes are available at similar prices to the cheapest of the small engine pipes really makes it a no brainer if you're buying new. If you just want the best deal you can find, it is most likely you can pick up a used Leo Vince SP3 or ZX for a 50-70cc on eBay or craigslist cheaper than any other aftermarket exhaust though. They're very common. To farther make that point, I bought both of those pipes used myself and paid $100 under retail for each. I got lucky on the SP3 deal, but it was cheaper than I can normally find stock pipes.
My pick is once again very easy to make. I would choose the Phongeer over any pipe tested for a regularly ridden street scoot hands down. It's price is even with the cheapest of the pipes purchased new. It performs better than any other pipe suitable for regular street use. The 100cc ZX shows the same numbers for cruise and max speeds, but it needs to operate at a higher RPM than the Phongeer to make it's power. The Phongeer seems to have the widest powerband of any pipe I tested. Not only is it more comfortable at lower revs than the other pipes, but it also seems to work better at higher RPM than the other street style exhausts. You can get great performance out of the Phongeer, and the average Joe won't even notice it's not a stock pipe. The only real drawback for the Phongeer for me is the poor fit. I have used this exhaust on both long and short case engines and it needed an adapter to be made to work with either. The header comes in contact with the large fan shroud on Project 90 and did burn a small hole in it, but it has not seemed to affect operating temperatures. In my opinion it is well worth the effort to fit, but be aware of this if you are looking for a pipe that bolts on with little hassle. You can see the fitment details HERE.
My second choice would be the Leo Vince ZX 100cc or the YMS V8. It depends what is most important, more performance or less spending. The ZX did outperform the V8, but it costs $100 more for a gain of about 1MPH on max and cruising speed. It's easy to see the ZX is a performance pipe, while the V8 remains stealthy. One other big factor here could be fitment. If you go back to the original tests for these pipes (100cc ZX HERE, V8 HERE), you will see that the ZX fit relatively trouble free while the V8 took major work to fit. I do think I must have got a dud with the V8, but I still suggest looking around for more reviews before purchasing.
If your goal is max power at any expense, look no farther than the Peace Pipe. Get yourself a big carb and a cylinder with long port durations as well as a trick CVT setup and your scooter will haul ass when properly tuned. Unfortunately I find it way too loud for street use and I really dislike needing to remove the centerstand. Make no mistake though, the Peace Pipe far outperforms anything else tested. I think this pipe could push you to some pretty crazy speeds and very quick acceleration with the right parts supporting it.
Everything else basically fell into the OK, but not great category. The only exception possibly being the Leo Vince GP. That's not at all based on performance though. It's the pipe I'd choose if I wanted to build a show scooter. Spend some time polishing up the stainless steel and it's a beautiful piece.
So there you have it. There's really no one clear winner for all tastes. If you don't mind a little fitting work, the Phongeer is a strong and stealthy performer. The 100cc ZX bolts up easier, but it's not as stealthy, has a little more narrow powerband, needs more revs, and costs $100 more than the Phongeer. The YMS V8 is close behind the ZX in performance and costs $100 less, but it's fit is questionable. The GP is a pretty face with average performance. The 50-70cc ZX and SP3 are average performers as well, but they're the most likely of all the aftermarket pipes to be found at very low prices used. The Peace Pipe destroys the competition as far as performance, but falls well behind in being real world friendly. The winner for you depends on exactly what you're looking for out of an exhaust.
I've tried all of the pipes, other than the MRP that caused engine damage in Phase 2, once again, but with a larger carburetor and intake setup this time around. I think the results more accurately show each pipes abilities in this phase than they did in phase 2, so let me start off by going back over some of the info acquired. Refer back to individual tests for full details on each exhaust.
*Prices may vary depending on seller and shipping charges. All prices assume no installation fees and account for no additional parts.*
Exhaust | Max Speed | Cruise Speed | Comments | Price |
Stock | 57MPH | 48-50MPH | Quiet, draws no attention, and cheap because you probably have a stock pipe around. Did well considering it's a 49cc stock exhaust on a 96cc modified engine. | N/A |
Leo Vince GP 50-70cc | 59MPH | 50-53MPH | Offered an improvement over stock and sound levels that don't attract attention. Best looking pipe of the bunch IMO. The $100 over the SP3 should only be spent if it's look is worth that much to you. It does feature largely stainless steel construction, but the steel header and other parts mean it's not immune to rust. | $250 |
Leo Vince SP3 50-70cc | 59MPH | 50-53MPH | Offered an improvement over stock with plain looks and and sound levels that don't attract attention. Affordable and easy to find. | $150 |
Leo Vince ZX 50-70cc | 59MPH | 50-53MPH | Offered an improvement over stock, but not nearly as much as the version designed for this displacement. Needs to rev higher to get similar results to the 50-70cc street pipes. Reasonable sound levels. Easy to find, and not uncommon to find used cheap. | $250 |
Leo Vince ZX 100cc | 61MPH | 52-54MPH | Nice gains in cruise and max speed. It does need to rev a little higher than some other pipes to achieve those gains. Reasonable sound levels. Harder to find than a lot of the pipes tested. | $250 |
Peace Pipe | 64MPH | 55-58MPH | Loud, no center stand allowed, and harder to tune. Power output exceeds any other pipe tested. Needs to operate at the highest RPM of any pipe tested. Best for race or a weekend toy, not for a daily rider IMO. | $250 |
Phongeer | 61MPH | 52-54MPH | Nice gains in cruise and max speed without flashy looks or sound. Wide powerband. Not available from many retailers, but can be found and at an excellent price for the performance it offers. | $150 |
YMS V8 | 60MPH | 51-53MPH | Offered nice gains over stock with plain looks and sound. Pretty easy to find, and at a reasonable price. | $150 |
Main Jet Changes
Exhaust | Jet Size | Size Change | Percent Change |
Stock | 95 | N/A | N/A |
Leo Vince GP | 100 | +5 | +5% |
Leo Vince SP3 | 100 | +5 | +5% |
Leo Vince ZX 50-70cc | 98-100 | +5 | +5% |
Leo Vince ZX 100cc | 100 | +3-5 | +3-5% |
Peace Pipe | 105 | +10 | +11% |
Phongeer | 100 | +5 | +5% |
YMS V8 | 102 | +7 | +7% |
Exhaust Sound Level Comparison
Since a big part of an exhaust system's job is to keep things quiet, I wanted to test a few pipes to see just how well they do that job. I tested the stock exhaust, Leo Vince GP, Leo Vince ZX, Peace Pipe, and the Phongeer exhaust. You may have noticed that I left out the Leo Vince SP3, the 50-70cc ZX, and the YMS V8. The two ZX pipes sound the same. The street style exhausts were all so similar in sound that I opted to exclude the SP3 and V8 to save time and gaskets.
I used an SPL meter to give results in decibels (dB) at idle, 5,000RPM, and WOT. The meter was placed 6ft from the corner of the rear tire on the exhaust side at roughly a 45 degree angle. I felt this method would be most fair since some pipes had a side outlet and others had a rear outlet. I marked all locations with masking tape so I could be certain that results stayed fair for every pipe. I used a stock airbox to keep the modified airbox from having an effect on dB levels.
Exhaust | Idle | 5,000RPM | WOT |
Stock | 62dB | 77dB | 91dB |
Leo Vince GP | 69dB | 78dB | 91dB |
Leo Vince ZX | 69dB | 77dB | 91dB |
Peace Pipe | 75db | 83dB | 101dB |
Phongeer | 67dB | 75dB | 88dB |
www.youtube.com/watch?v=BszoxG7W1RA
As I mentioned in the baseline for this phase, the stock pipe is has something loose inside of it that rattles around. I haven't noticed a change in sound, but I can't swear that it's exactly the same as always. I can't imagine that it's very far off of where it should be, if off at all.
All of the street style pipes did an excellent job of keeping the engine quiet. Once past idle, they are right on par with the stock exhaust. The Phongeer even did a better job of quieting the engine at high RPM than stock. I was surprised to see the Leo Vince ZX keeping up with the quiet street pipes. The Peace Pipe was the standout of the group with much higher readings.
For anyone not used to looking at dB readings, there are a few things to note here. Sound pressure level does not always accurately reflect perceived loudness. SPL is an objective measure, while loudness is a subjective measure as perceived by a human. It is said that an increase of 10dB is roughly equal to double the perceived loudness. Human hearing is also more sensitive to certain frequencies, so different exhaust notes can be perceived as louder even at the same sound pressure level.
Technical mumbo jumbo aside, the Peace Pipe is LOUD. It's loud enough that I suggest a full face helmet and/or ear protection on long rides. It could cause hearing damage depending how long you are exposed to it. Otherwise, the pipes aren't bad. Even though the ZX shows similar dB readings as the street pipes, it is louder in the real world. I think a few factors are at work there. One is the tone of the pipe, perhaps it falls into a more sensitive area of hearing. Another, which I feel is the major contributor, is the location of it's outlet. Pipes that exit to the side tend to sound louder than the ones with a rear exit while you ride. Lastly, the ZX operates at a higher RPM than the street pipes and volume increases with RPM. The stock and street exhausts are mostly staying in the neighborhood of 8,500RPM at WOT, while the ZX pushes above 9,000RPM. The Peace Pipe takes it even farther wanting to go to 10,000RPM or beyond with the right setup. On the stand for the test they all revved out close to 10,000RPM under no load.
To make a long story short, any of the pipes I have tested aside from the Peace Pipe should be OK on the street as far as volume is concerned. With the street style pipes you can tell a difference in the sound, but it's not huge. The ZX is actually louder, but it's still not something that should get you into trouble based on sound. The Peace Pipe will draw a lot of attention and is very loud to ride with.
Conclusions
The first thing I've seen here is that a larger than stock carburetor and intake track is very beneficial to a piped 90+cc engine. Not only does it increase performance, but it keeps the engine cooler. In the case of the Peace Pipe, the stock carburetor wasn't even capable of keeping heat down enough that the scooter was able to be ridden for very long. Lower temps are easier on parts and could help to extend engine life.
It became much more apparent this time that choosing a pipe intended for your displacement is important. Even if the pipe for a 50-70cc is designed in a manner that doesn't damage the engine, it's not designed to handle the larger volume as well as the 90-100cc specific exhausts. Every 90-100cc pipe outperformed every 50-70cc pipe. The fact that some of the big engine pipes are available at similar prices to the cheapest of the small engine pipes really makes it a no brainer if you're buying new. If you just want the best deal you can find, it is most likely you can pick up a used Leo Vince SP3 or ZX for a 50-70cc on eBay or craigslist cheaper than any other aftermarket exhaust though. They're very common. To farther make that point, I bought both of those pipes used myself and paid $100 under retail for each. I got lucky on the SP3 deal, but it was cheaper than I can normally find stock pipes.
My pick is once again very easy to make. I would choose the Phongeer over any pipe tested for a regularly ridden street scoot hands down. It's price is even with the cheapest of the pipes purchased new. It performs better than any other pipe suitable for regular street use. The 100cc ZX shows the same numbers for cruise and max speeds, but it needs to operate at a higher RPM than the Phongeer to make it's power. The Phongeer seems to have the widest powerband of any pipe I tested. Not only is it more comfortable at lower revs than the other pipes, but it also seems to work better at higher RPM than the other street style exhausts. You can get great performance out of the Phongeer, and the average Joe won't even notice it's not a stock pipe. The only real drawback for the Phongeer for me is the poor fit. I have used this exhaust on both long and short case engines and it needed an adapter to be made to work with either. The header comes in contact with the large fan shroud on Project 90 and did burn a small hole in it, but it has not seemed to affect operating temperatures. In my opinion it is well worth the effort to fit, but be aware of this if you are looking for a pipe that bolts on with little hassle. You can see the fitment details HERE.
My second choice would be the Leo Vince ZX 100cc or the YMS V8. It depends what is most important, more performance or less spending. The ZX did outperform the V8, but it costs $100 more for a gain of about 1MPH on max and cruising speed. It's easy to see the ZX is a performance pipe, while the V8 remains stealthy. One other big factor here could be fitment. If you go back to the original tests for these pipes (100cc ZX HERE, V8 HERE), you will see that the ZX fit relatively trouble free while the V8 took major work to fit. I do think I must have got a dud with the V8, but I still suggest looking around for more reviews before purchasing.
If your goal is max power at any expense, look no farther than the Peace Pipe. Get yourself a big carb and a cylinder with long port durations as well as a trick CVT setup and your scooter will haul ass when properly tuned. Unfortunately I find it way too loud for street use and I really dislike needing to remove the centerstand. Make no mistake though, the Peace Pipe far outperforms anything else tested. I think this pipe could push you to some pretty crazy speeds and very quick acceleration with the right parts supporting it.
Everything else basically fell into the OK, but not great category. The only exception possibly being the Leo Vince GP. That's not at all based on performance though. It's the pipe I'd choose if I wanted to build a show scooter. Spend some time polishing up the stainless steel and it's a beautiful piece.
So there you have it. There's really no one clear winner for all tastes. If you don't mind a little fitting work, the Phongeer is a strong and stealthy performer. The 100cc ZX bolts up easier, but it's not as stealthy, has a little more narrow powerband, needs more revs, and costs $100 more than the Phongeer. The YMS V8 is close behind the ZX in performance and costs $100 less, but it's fit is questionable. The GP is a pretty face with average performance. The 50-70cc ZX and SP3 are average performers as well, but they're the most likely of all the aftermarket pipes to be found at very low prices used. The Peace Pipe destroys the competition as far as performance, but falls well behind in being real world friendly. The winner for you depends on exactly what you're looking for out of an exhaust.
Great detailed write-up! 
