So the White SP is behind the eight ball in everyway concerning maximizing a stage 2 upgrade with the S1 cam yet it remains my favorite to ride. Consider what it has going against it for a beneficial outcome for a stage 2 build:
Just an open air box cover (TST) - not a customized intake like the dinger, chimera, mnnthbx etc...
A Yoshimura slip on muffler - not the full loop choice 95% of Grom owners go with.
It has the OEM header pipe with inline catalytic converter that isn't as free flowing.
It has the Yoshimura sound insert plugged in the end.
Non-Premium regular 87 octane gas.
David at DHM worked with me and setup an identical bike with these exact parameters to create my tune. I was very specific about pointing out this was the slip-on muffler not the full loop exhaust and it had the Yoshimura SOUND INSERT KIT for RS-9 Muffler, 1.250" (INS-RS9B-K). And I wanted to use 87 octane gas, not the 93 octane that he normally uses when developing a fuel map. And the TST Worx intake was going to be used with the stock OEM Grom air filter only.
So what is the result? About exactly the same as the Racerboy performance. I know right? Surprising! If I had to be specific I would have to say the Racerboy might have a bit more mid range power.
The end result though is fantastic. This combination of detriments has resulted in a bike that sounds like pure heaven when wailed upon. It's not tiring to the ear at speed nor excessive in populated areas. It provides for a mellifluous harmonic experience on the road. I'm loving it. That's why it's my favorite.
Kudo's to DHM for creating a fuel map flash where there are no dips, hesitations, pops, or crackling. Just perfect and spot on. Pulls nice and even through the entire rev range and every gear.