I'm contemplating doing the S&S 98" big bore kit and S&S 510 cams in my 2003 Electra Glide Classic; I was wondering if anyone had done anything similar and if so, how much, if any, did your fuel mileage suffer?

Currently I have a 88" injected bike with Vance and Hines Dresser Duals, a Vance and Hines VO2 intake, Dynojet Power Vision tuner, and S&S 509 cams.

Just looking for others input before I go spending a bunch of money.

 

Do you have the wide band kit for that PV? If so, and you know how to use it, your mileage won't drop all that much while cruising.

 

I do have the Wideband kit.

 

I still get low to mid 40's

 

I would not put the 510's in, they are soft down low, something better would be the Andrews 37's in my opinion, really depends what you are doing with them, but for a heavy bagger either the Andrews 26 or with the big bore and higher compression the 37's.

I did the S&S 97 inch big bore, had SE204 cams until I went gear drive, I have a carb and am getting 34 to 36 mpg

 

I don't think any of us suffers with reduced fuel mileage when making engine mods, except when using the extra performance!

 

got BB, SE heads, S&S 570 Ezstart cams and gear drive....at 55 to 60...46 mpg.. after that it dropped to around 40-42

 

I have the (TC 98" big bore kit 9.75:1 CR ,Andrews 37G cam, RP Hydro-Rev Lifters, HD Adj pushrods, CometicTop end Gasket set #1zx74w890352001874 , Basle Oil spring, Street Port on Heads) and the SE Tuner in my 2005 Ultra. I am running the Vance and Hines Dresser Duals and Ovals.
It was tuned to run on 89 octane as I can’t always find 91 on the road. I get (if I don’t start to play with it passing trucks) 36 to 40 mpg loaded and two up. At 2K RPM I have 100 TQ and Top out at 107 TQ and 97 HP. The TQ doesn't start to drop off till 4.5K RPM so I am always in the TQ band.

 

Hillside 98" Andrews 37- I'm getting 40-45, but I have a lighter bike.

 

You are going to find that when properly done, and with an expert tune, mileage doesn't suffer much........... the problem is, with a performance build you will find that the problem will be with your right wrist. That will be where your fuel economy will go way down.

My 05 RG had a stage 4, and if I kept it on cruise control, I could get 44-48 on level roads and just flowing with traffic.

Take it off cruise and let my right hand control it, and I could watch my gas gauge go down, and my grin get bigger.