100 hp evo
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,897
From: Bedford UK
I swapped mine for an S&S 107".
It can be done, but only with some serious modifications. How much can you afford? There are HDF sponsors who are tuning specialists who can probably advise what to do, also do it for you.
It can be done, but only with some serious modifications. How much can you afford? There are HDF sponsors who are tuning specialists who can probably advise what to do, also do it for you.
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,070
Likes: 2,115
From: Ohio
More cubes a GR mentioned, you can get 100 hp out a 80" Evo but your talking high compression, big lift cam and heads flowing that will struggle with street manors. It is safe to say that you will have as much money in the 80" as a larger cube motor so step back and compare, if you want a stock cased HD engine then put a 4 5/8 S&S rotating assembley in with headwork and matching cam, 100 hp is easy and that is the route I went but had no labor costs, if you need to have someone build the engine then option B of the new big cube engine comes back in.
Last edited by 1997bagger; Mar 24, 2013 at 04:12 PM.
Cruiser
Joined: Dec 2008
Posts: 214
Likes: 0
From: Peterborough, Canada
70-80 HP is a more realistic number to aim for with an 80 evo, if money is tight, cost is relatively low, and there is no real sacrifice in reliability. I have 50,000mi on build so far, and started pulling a trailer last year.
Last edited by Silver Ghost; Mar 24, 2013 at 10:37 AM.
Novice
Joined: Dec 2009
Posts: 23
Likes: 0
From: Pittsburgh, Pennsylvania
It can defiantly be done. I followed this as my build sheet for over the winter break. Probably going to have to wait till next winter for head work but gives you a good idea how to get there.
http://www.nightrider.com/biketech/hdbuildstage3_95.htm
http://www.nightrider.com/biketech/hdbuildstage3_95.htm
Seasoned HDF Member
Joined: Jul 2011
Posts: 27,096
Likes: 4,673
From: Frozelandia, Minnysota
Know a guy that built up his EVO 80ci top end, and soon trashed his lower end. The shop that did the work warned him it could happen, too. Was an earlier EVO than yours, don't know when/if Harley beefed up the lower end on EVO's. Is a very reliable engine otherwise, from what I've heard.
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Ultimate HDF Member
Joined: May 2006
Posts: 6,590
Likes: 444
From: Ohio
He was warned for good reason. It is customary to do both top and lower at the same time because a tight top is hard on a weak lower end.
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Advanced
Joined: Jul 2012
Posts: 51
Likes: 0
From: upstate ny
I built a 100hp 80inch actually 104hp but only 90something ft pounds of torque its a fun bike but needs 110 octane to run good with no detonation and is tempermental in traffic I just wanted to have a 80inch that surprised people and it does but youll never ever get the torque without the cubes . I did my bottom end . I would not trust stock evo cases with that kinda hp .
Road Warrior
Joined: Jan 2012
Posts: 1,410
Likes: 30
From: Waterville MN
I know horsepower numbers are great and all, but I ride with all newer bikes. After I did the EV27 and rejet, I ran with stage one 103 bikes pretty damn good up to 80 MPH or so, and ran about the same MPG. I know my HP numbers were not as high as theirs, but I had no trouble keeping up - and she is happy running on pump gas.