weird looking but still cool!
Tri-tip RMB
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Tri-tip RMB
A bit short of a Gemballa, but it fits in the stock cutout.
With 3 x 1.5" ID, it flows more than a single 3", but quiets the X-pipe down, nicely. It even has a O2 port for dyno testing.
I tried two of these resonator tips on straight pipe (previous muffler shop RMB), but I could tell there was some restriction, because it made that cool 'ripping silk' sound at full throttle. Still, it made 298 RWHP. With the extra tip and 'expansion chamber', and a bit more cam retard, I hope to get over 300 at Louie's this weekend.
With 3 x 1.5" ID, it flows more than a single 3", but quiets the X-pipe down, nicely. It even has a O2 port for dyno testing.
I tried two of these resonator tips on straight pipe (previous muffler shop RMB), but I could tell there was some restriction, because it made that cool 'ripping silk' sound at full throttle. Still, it made 298 RWHP. With the extra tip and 'expansion chamber', and a bit more cam retard, I hope to get over 300 at Louie's this weekend.
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It took a few days for me to get used to it, but I like it now.
Yep, they are parts store weld-on chrome resonator tips, 2.5" OD, to attach to a 2" pipe, IIRC. I cut off the neck down, and welded them to the 'expansion chamber', which is made of bits of 3" pipes, cut lengthwise. The first version resonated, so I put in the 3/4" pipe through the center, like the factory resonators have. I also put a 1/4" pipe across the entrance of the tips, about 1.5" away, with the thought that the turbulence created by the pipe would put more sound into the packing of the tips.
Yep, they are parts store weld-on chrome resonator tips, 2.5" OD, to attach to a 2" pipe, IIRC. I cut off the neck down, and welded them to the 'expansion chamber', which is made of bits of 3" pipes, cut lengthwise. The first version resonated, so I put in the 3/4" pipe through the center, like the factory resonators have. I also put a 1/4" pipe across the entrance of the tips, about 1.5" away, with the thought that the turbulence created by the pipe would put more sound into the packing of the tips.
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The light was fading, so the pic is not so good. It pretty much looks like a regular double from the rear. It is a little bit tilted, I'm just too lazy to loosen the clamps and level it.
This is kind of a cool shot (to me
), of the initial revision.
This is kind of a cool shot (to me
), of the initial revision.
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Chronic Tool Dropper
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From: Bend, Oregon
Originally Posted by PorKen
....
With 3 x 1.5" ID, it flows more than a single 3"...
With 3 x 1.5" ID, it flows more than a single 3"...
Ken, verify my math for me. A 1.5" diameter tube has 1.77 sq in cross-section, x 3 pipes is 5.3 sq in. A single 3" pipe has an area of a little over 7 sq in. There are some variables with surface area of the tube relative to cross section that make the smaller pipes even worse than above numbers might suggest, compared with a single 3". It also looks like there are baffles in your pipes. Are they considerd in the 1.5" pipe size?
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Bob,
I don't know about your math, but my math was wrong. It's a little bigger than a single 2.5" pipe. I guess I'll need a couple more...a five-tip would be almost 9²"
1.5" is the innermost open ID. The OD of each unit is 2.5".
Three pipes will have less flow, but it's easier to control the sound level, versus a single large pipe.
I don't know about your math, but my math was wrong. It's a little bigger than a single 2.5" pipe. I guess I'll need a couple more...a five-tip would be almost 9²"
1.5" is the innermost open ID. The OD of each unit is 2.5".
Three pipes will have less flow, but it's easier to control the sound level, versus a single large pipe.
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From: Portland, Oregon
Hey, Ken brought the car over to my house the other day and the first thing I noticed as he pulled into the driveway was the sound. I think I even said it sounded finely tuned. Had that well balanced European exhaust note. He showed me the tri-tip and this was the first thing that came to my mind ...
It needs one more pipe.
I remember his rear diffusers a couple of years back. I thought they were ridiculous, but ya know what? Ken comes up with more great ideas than not. So he can keep on comin' up with stuff no matter how foolish they may seem, cause you know he's got another one right around the corner thats gonna be a good one.
It needs one more pipe.
I remember his rear diffusers a couple of years back. I thought they were ridiculous, but ya know what? Ken comes up with more great ideas than not. So he can keep on comin' up with stuff no matter how foolish they may seem, cause you know he's got another one right around the corner thats gonna be a good one.