Sean Bowf
Well-Known Member
- Joined
- Sep 6, 2007
- Messages
- 716
OK...with all the hoopla about the new Q18 pipe, I picked one up and went to the pond today to try out the stock pipe, the Q18, MACS pipe, Cooper pipe, and the short AB pipe.
I did not do a lot of length adjustment on these pipes, because I wanted to see how they would do as a direct drop in replacement to the stock pipe. I spent A LOT of time trying to get the Q18 to work well, which did not leave me with a lot of time to mess with the others.
The boat was a stock version 1 miss vegas with a Y535 on it. Everything else was OEM (turn fin, rudder, header, etc, etc, etc) except a couple of non-performance parts. We were running 40% nitro with about 16% oil. The plug (made it through the whole test with one plug) was an OD blue. Speed was taken with an onboard Garmin GPS.
First we set a baseline with the stock pipe, to set a goal to beat. Best run we got was 32.1 MPH. Only took about three runs to hit this.
So, out with the stock pipe and in with the Q18. This pipe was VERY quiet. Almost sounded like an electric boat. Start leaning it up an eighth turn at a time until the speed went down, then started richening it back up an eighth turn at a time until it sped up and then slowed back down. Because it was not turning the prop very well, I raised the prop up to see if I could get some more speed from RPM instead of a deeper prop. Out of 8+ runs, the best speed I could get 30.6 MPH. Most runs were mid 20s.
Out with the Q18 and in with the AB short .21 pipe made for 180 degree headers. This is the pipe I run in my mod RTR. Anyhow, I did not have the stuff with me, or the will to fool around with trying to get the pipe to stay where it belongs (it is a shorter pipe than the stock one. So we only made one run with it, during which it came loose. The speed was about 30 MPH. With a header extension, I think this pipe would do better...
Next up was the Cooper QHP pipe. This pipe was quiet too, but not as quiet as the Q18. Best we could muster out of this pipe was a little over 30 MPH...IE 30.xx MPH. Only tried about 5 or 6 runs with it.
Next up was the MACS .21 pipe. This pipe was the one I used to run in my mod RTR before I got called for noise (it is unmuffled). So, it was already cut to fit into the stock location of the OEM pipe. MACS pipes have always been easy to tune for me...within three runs we hit 33.3 MPH, and then we hit 34.2 MPH...so we did not try any more.
Last, we put the stock pipe back in just to make sure the weather heating up was not adversely effecting our runs. We hit 32.7 MPH with the stock pipe in on the first run with it back in.
So...without cutting, and modding a bunch of stuff, it looks like the MACS pipe was the best pipe of the day...with the stock one coming in second.
If I get some more time to do some testing, I might try some other stuff with the pipes...but short of trying them a little longer (most seemed to have their widest point shorter than the MACS pipe), I am really at a loss of what else to try. Any ideas?
Sean
I did not do a lot of length adjustment on these pipes, because I wanted to see how they would do as a direct drop in replacement to the stock pipe. I spent A LOT of time trying to get the Q18 to work well, which did not leave me with a lot of time to mess with the others.
The boat was a stock version 1 miss vegas with a Y535 on it. Everything else was OEM (turn fin, rudder, header, etc, etc, etc) except a couple of non-performance parts. We were running 40% nitro with about 16% oil. The plug (made it through the whole test with one plug) was an OD blue. Speed was taken with an onboard Garmin GPS.
First we set a baseline with the stock pipe, to set a goal to beat. Best run we got was 32.1 MPH. Only took about three runs to hit this.
So, out with the stock pipe and in with the Q18. This pipe was VERY quiet. Almost sounded like an electric boat. Start leaning it up an eighth turn at a time until the speed went down, then started richening it back up an eighth turn at a time until it sped up and then slowed back down. Because it was not turning the prop very well, I raised the prop up to see if I could get some more speed from RPM instead of a deeper prop. Out of 8+ runs, the best speed I could get 30.6 MPH. Most runs were mid 20s.
Out with the Q18 and in with the AB short .21 pipe made for 180 degree headers. This is the pipe I run in my mod RTR. Anyhow, I did not have the stuff with me, or the will to fool around with trying to get the pipe to stay where it belongs (it is a shorter pipe than the stock one. So we only made one run with it, during which it came loose. The speed was about 30 MPH. With a header extension, I think this pipe would do better...
Next up was the Cooper QHP pipe. This pipe was quiet too, but not as quiet as the Q18. Best we could muster out of this pipe was a little over 30 MPH...IE 30.xx MPH. Only tried about 5 or 6 runs with it.
Next up was the MACS .21 pipe. This pipe was the one I used to run in my mod RTR before I got called for noise (it is unmuffled). So, it was already cut to fit into the stock location of the OEM pipe. MACS pipes have always been easy to tune for me...within three runs we hit 33.3 MPH, and then we hit 34.2 MPH...so we did not try any more.
Last, we put the stock pipe back in just to make sure the weather heating up was not adversely effecting our runs. We hit 32.7 MPH with the stock pipe in on the first run with it back in.
So...without cutting, and modding a bunch of stuff, it looks like the MACS pipe was the best pipe of the day...with the stock one coming in second.
If I get some more time to do some testing, I might try some other stuff with the pipes...but short of trying them a little longer (most seemed to have their widest point shorter than the MACS pipe), I am really at a loss of what else to try. Any ideas?
Sean
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