I met a gentlman on another site who is familar with Harleys, big motors, dynos, etc. I talked with him on the phone at length last night and for the 103" with high flow air cleaner, Race Tuner (or PC III) he suggests a 2 into 1 exhaust (he did not recommend a particular make). He talked at length about "peak HP and peak torque" vs. usable HP and usable torque (in the lower end of the power band. I explained that I don't care so much about 120 mph power, that I'm interested in stop to 80 mph.....he suggested the 2 into 1. He made it clear that he does not want to beat anybody up or their exhaust system but it's what he knows to work on the big inch motors (unless you're going to be doing more riding on the drag strip than the street). By the way, in two weeks he'll be moving to Ariz. to start his new job of running the Dyno department at MMI. I also gave him the direction to this web site.....hopefully he will spend some time over here sharing his technical experience and opnion.
Here is the map on a 103 crate motor if you notice the TW5 made up for a big loos in TQ in the dip. ANd then pulled away from there on. The TW5G is a great fix for the SE cam. I do amny of these as they offer a direct swap without changing valve springs. Notice the exhaust system. Rheinhart( they stink) they are a more mid to upper pipe with a big loos on the bottom end. This is what that pipe offers. For your set-up a TW5G cam and a good pipe will make your scooter be able to pull a house. !!! Let meknow if there is anything elese I can do for you.
GMR PERFORMANCE 1-810-650-6403
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