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Vance & Hines FP3 Initial Review
2017 XG750A Street Rod
S&S Stealth Intake
Rinehart Muffler
Custom map number 3357734 from V&H dyno tuner was used to accommodate S&S Stealth intake.

I had a hard time ending my ride because I was giggling under my helmet like a little girl but I really wanted to get back to sharing initial thoughts.

Throttle feel and response gets better and better as I ride and the ECM trims AFR. In my opinion the stock EFI has a herky-jerky response and I have always hated it. Now it feels great.

Bike makes less noise under part-throttle cruising/riding with no load (i.e., flat and no wind) and I assume this is due to engine making more power due to higher efficiency and needing less throttle position. However, under heavy and WOT throttle it sounds entirely different. Quite a bark this little engine now makes and it sounds magnificent.

Normal riding, say from idle to 1/4 throttle and idle to 4,000 RPM, it feels about the same but without that herky-jerky response. Engine responds very well to small inputs though I feel stock map responded just a bit better. Even so it may continue to get better and I will trade that for herky-jerky any day. Small inputs under heavy load or in high gears (short-shift) also feel pretty similar to stock and this is just fine as I feel stock was pretty good.

Normal riding, say from idle to 1/4 throttle but from 4,000 RPM and above the whole world changed. Response is instant and immediate. Power comes on strong and just keeps on coming - It's an entirely different engine now. Where the stock engine responded okay and in sort of a smooth linear fashion it now feels more like a switch was thrown. Sort of like a modern metric sport bike when its engine speed is up very high.

Harder riding, say from 1/2 throttle and above and from 4,000 RPM on up the engine feels completely different. It takes far less time for the engine and bike to gain speed and a few times I looked down and I was going 70+ in a 45. These are roads I am always on and that has never happened in the past. It literally feels like it has more displacement or has had a cam and piston upgrade the way it pulls from mid on up. Power never seems to stop and the ways it comes on is quite addicting and exhilarating.
When I stopped to top off the tank and to key cycle as recommended I noticed the engine was not as hot as I am used to and I assume this is due to a bit lower AFR. I noticed the same when I stopped and parked in the garage.

The V&H Dyno Tuner I have been working with was nice enough to provide me with a dyno sheet and the increase in RWHP was 10.5% with V&H High Outpupt pipe, V&H VO2 intake prototype (like S&S Stealth), and FP3 tuner. The TQ was still good at 9,500 RPM and HP was still being made at 9,500 RPM.

The FP3 has met all my expectations and this is now an entirely different machine. I had no idea just how much was left on the table with the stock ECM map...
V&H just told me I can share where this map came from so here it is: https://www.bikeexif.com/street-rod-750

V&H development of custom FP3 maps include work for Noise Cycles, Suicide Machine Co, The Speed Merchant, the Rusty Butcher, and even a guy called Turbo Trey who brought his boosted Street 500 from TX. V&H have tuned a bunch of the local Hooligans' bikes in their shop.


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