Hey Ken, I've read a lot about Frank Drago's pipes on the other forums, and am debating on whether I should switch to the S/C/S-4. I presently run the Fullsac b pipe and Rinehart 4" cans.
I was planning on phoning Frank to discuss the Dragula vs the S/C/S-4, specifically regarding the stepped vs non-stepped point. But, I see you already had that discussion with him, so this confirms my belief that the S/C/S-4 is a better choice than the bigger Dragula, for our stock/mildly modified 110's and the desired low end tq.
So now that your buddy is running the same exhaust combo as me, how would you compare the sound of your pipe vs the Fullsac/Rinehart 4" combo?
You said your S/C/S-4 made a huge difference power wise over your previous Fullsac combo? Are we talking low end pull? Hows the mid-range and the throttle response/lag?
The 2-1 is a
very different sound than the Fullsac/Rinehart 4" setup.
First, I'll say that I have always loved the sound of Rineharts - probably the most "Harley"-sounding of any mufflers I've heard. Nice and loud, but not obnoxious.
2-1 pipes have a quite different sound. Because of the massive mixing in the collection chamber, and all of the exhaust gas exiting through a single muffler - you don't really hear each individual cylinder firing nearly as much. You hear a smoother type of exhaust note that I love, but some don't like. However, you can't beat a 2-1 for performance. The S/C/S-4 uses the Dragula 4.05" muffler, so the sound is basically the same as the Dragula - but the collector is different, and of course the headers are straight.
It does perform better than the Fullsac setup - but not hugely so... not yet anyway. I haven't come close to finishing my tune yet. I am basically going to start over with a TTS MT8 map, so I can have access to the EGR and cam selector settings for fine-tuning the low-end RPM - idle to about 1,700 - in open loop. This will help with getting the best off-idle throttle response, and with eliminating decal popping since you get a lot of breather gas in decal ranges and need to richen them up. I also run open loop above 4500 RPM as well. I don't have the throttle response and off-idle where I want it yet. Even with the Fullsac, I have found that with a TBW bike you can't just twist the throttle all the way open off-idle like you can on a cable throttle bike. It's much better to open it smoothly up to about 80% throttle than it is to just yank it open - at least on Buster. But that may be because I don't have the low end dialed in correctly yet.
With my 54H cams, I am never going to get screaming off-idle performance though. Because of the 238/238 duration, intake valve timing, lobe center, and overlap - 54Hs are NOT low-end cams. The really don't even "come in" until about 2700 RPM... but then they light up. So, if I am running someone, I need to get the revs up before dumping the clutch - so the engine is in its highest-torque "Happy Place" of 3000-5000 RPM!
Tuning a 2-1 is more difficult than a 2-1-2 setup like the Fullsac... you have to be patient and collect a lot of data in order to get the various kPa/RPM ranges all dialed in correctly - at least the ones you ride in. We have had to move the cubic inches all the way up to 127" to get the various kPa and RPMs ranges under 100 VE so the ECM isn't having to guess. This will be an extended process - but I'm willing to do it to get the best tune I can. We will probably have to do some manual tweaking of the VE tables to smooth things out, too... with a 2-1, the VE numbers in adjacent boxes seem to jump around more than with a 2-1-2. Don't really understand why - but they do.
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Topic: NorthGeorgiaHawg's FLHXSE3 Mods (Read 105028 times)