Don't agree with it being more touchy, but they do make the motor more responsive and responds more noticeably to jetting changes. IMO, that is a good thing. If you're not willing to spend time tuning them initially, I would advise against them. Once tuned, they work well. Your sled will also run better overall than it did without the UFOs. Before you install them, call Lonn at Thunder Products and ask all of the questions you have. If you are an inexperienced tuner, admit it, and ask for help or you will be frustrated with UFOs.
I install them in every round slide carb sled I have ever owned. LOVE them!!1 Simple as can be, just cut your pilot jet by half and you will be good to go. Jetting is NOT touchy at all, and that thing will be snappier then all get out! HIGHLY RECOMMENDED
With mine, 98 XCR 440, I went from a 45 pilot to a 17.5 and my stock slides were 2.0s and are 3.5s with the UFOs. It is very common to end up at less than 1/2 of the original pilot. For this reason, I called to talk to Lonn at Thunder Products so I had all the jets I might need to dial it in. The sled will run good but get terrible fuel economy if not tuned correctly.
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