hello everybody my name is nuno and im from south texas and i own a 2003 fatboy 100th anniversary edition and few month back i purchased a hd 103 engine from the hd dealership in austin tx, come of a 2016 street glide so i was told by the service and parts guys there, and i was thinking about upgrading my twin cam 88 with this 103 engine i also purchased a hd six speed transmission from an 08, model my thing is will this combination work the 103 engine with a earlier model 08 six speed together if i were to do the engine swap any info on this will be very useful . or should i just build a bike with this set up? i kinda want my fatty with more horses !!

 

Welcome.

 

Welcome from North Beach, FL., USA!

Just in case you have not done both of these two important items!

Be sure to add an Avatar of your favorite shot in the USER set up for the small picture others will see in the top left corner of your post with your USER name.

And most importantly a Signature Line in your USER set up for your bike model, year, and all the letters that Harley recognizes it with that others see at the bottom.

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Welcome to the Forum lots of good information here

 

A Fatboy would need a 103B motor. Street glide has the unbalanced 103. Totally different animal I think.

 

Welcome from Spartan Country, Michigan!
I tell a lot of new comers to the forum to get: Factory Service manual and the Parts manual. Get a three ring binder and record all your maintenance, repairs, accessories, etc. This will be a great reminder of what was done when. And great material to pass along to the new owner should you sell and upgrade. Also know how large your fuel tank is, a rough idea of your range per tank, and record your fuel usage. I have an app called Simply Auto that I record all my fuel used. I use the odometer and use the fuel gage as reference only. I reset the odometer to zero on fill ups, and I know I can safely get 200 miles on a tank on around town riding, and upwards of 230+ on trips.
Good Luck!!

 

The Twin Cam "A" engine/trans combo used in Touring bikes is different from the Twin Cam "B" engine/trans combo used in Softail bikes.......

The frames and engine/trans mounts between a touring bike and a softail are different.... The transmission housings, and how they mount to the engine and rear swing arm, are different between an "A" engine and a "B" engine.

I have a friend who says, "Anything is possible with enough time and money".... That engine/trans swap would not be possible without major modifications, an awful lot of time, and a rather large pile of money.....

You'd be much better off getting a Stage IV kit for your FatBoy from one of the vendors on this forum, that could set you up with good parts that are compatible and work well together to achieve your power goals.... It would be easier, cheaper, and more satisfying in the long run...

I'm curious why you bought a 103" Twin Cam "A" touring engine when you own a softail...??? Regardless of the reason, you can either build a touring bike around that engine, resell it to someone with a touring bike looking for that type engine, or put it on display as wall art...

Good luck with your decision...

 

Welcome from New York.

 

Hello and welcome to the HD Forums from West Virginia (USA). Glad you have joined us all here.