2014 103 Cam
Outstanding HDF Member
Joined: Aug 2009
Posts: 2,858
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From: Puyallup Wa.
what is a EPA cam? exactly how does that work?
Road Warrior
Joined: Apr 2010
Posts: 1,648
Likes: 37
From: Monroe, Louisiana
It is designed to have low emissions output. They do this by having very low or no overlap on the split overlap stoke which is the stoke opposite of compression stroke. It is low duration and the timing of the intake opening BTDC is very low or even opens 12 degrees ATDC and the exhaust closes 4 degrees after TDC. A cam such as the SE204 the intake opens 34° earlier than the stock cam and the exhaust closes 4° later. It also has 36 more degrees duration on intake and 18 on the exhaust. The 204 is a fairly mild cam, but is not an emissions cam. The more overlap the less efficient the cam is at low rpms and therefore more emissions emitted.
The Stock cam and the SE 255 are the only two EPA compliant cams. There may be others but I am not aware of them.
The Stock cam and the SE 255 are the only two EPA compliant cams. There may be others but I am not aware of them.
Ultimate HDF Member
Joined: Mar 2012
Posts: 6,129
Likes: 143
From: Santa Cruz
EPA compliant means they they are able to pass EPA emissions testing. Actually 255/254/259 are EPA compliant (with proper components). Harley really isn't making performance cams anymore. I'm a little surprised they still sell 204 for newer bikes.
Road Warrior
Joined: Apr 2010
Posts: 1,648
Likes: 37
From: Monroe, Louisiana
Actually the E on the end of the 254 and 259 is for Electronic Fuel Injection. That is what they were designed for. If the 259E is EPA compliant then a lot of the after market cams would be complaint as the 259E has 246 intake duration and 250 on exhaust and has .579 lift. That is more duration and lift than all the TW 555, 777, or 888. The 255 has 211 intake and 235 exhaust and .556 lift and is the only other cam epa compliant besides the stock cams.
Ultimate HDF Member
Joined: Mar 2012
Posts: 6,129
Likes: 143
From: Santa Cruz
Actually the E on the end of the 254 and 259 is for Electronic Fuel Injection. That is what they were designed for. If the 259E is EPA compliant then a lot of the after market cams would be complaint as the 259E has 246 intake duration and 250 on exhaust and has .579 lift. That is more duration and lift than all the TW 555, 777, or 888. The 255 has 211 intake and 235 exhaust and .556 lift and is the only other cam epa compliant besides the stock cams.
Road Warrior
Joined: Apr 2010
Posts: 1,648
Likes: 37
From: Monroe, Louisiana
You are correct on the stage IV legal kit. How good it works without a tuner and only the Harley download I would have to see that. It also has to be installed at time of purchase to maintain Limited Warranty. You can't use the SEPST as it is not legal on the street.
Road Warrior
Joined: Apr 2010
Posts: 1,648
Likes: 37
From: Monroe, Louisiana
They are actually both on a 105 center line. The new has a 103.5 intake cl and the 255 has a 99.5 intake cl which is 4 degrees advanced. The new has 106.5 exhaust cl and the 255 has a 110.5 exhaust cl which is 4 degrees retarded. This make both have a 105 cl. I still don't know the lift on the new cam. I suspect they will be pretty equal with the 255 cam. The new cam has more retard on intake and more advance on exhaust. They both have 13 degrees overlap. Who knows how it is going to perform. I bet not much difference. That 10 to 1 on the Twin cooled should make difference.
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Seasoned HDF Member
Joined: Jun 2007
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From: North of Hell, South of Heaven
They are actually both on a 105 center line. The new has a 103.5 intake cl and the 255 has a 99.5 intake cl which is 4 degrees advanced. The new has 106.5 exhaust cl and the 255 has a 110.5 exhaust cl which is 4 degrees retarded. This make both have a 105 cl. I still don't know the lift on the new cam. I suspect they will be pretty equal with the 255 cam. The new cam has more retard on intake and more advance on exhaust. They both have 13 degrees overlap. Who knows how it is going to perform. I bet not much difference. That 10 to 1 on the Twin cooled should make difference.
Road Warrior
Joined: Apr 2010
Posts: 1,648
Likes: 37
From: Monroe, Louisiana
Actually what I am saying is the new cam will be better than the stock 103 cam and will build less cranking compression than the 255. The 10 to 1 with a 255 even with compression releases would probably be a ping monster and hard on starters. When FM does their testing on the 2014 FLHTK we should have a better idea. I do think it will be equal to the 255 and the power band will move a couple hundred rpms to the right. I still don't know the lift so will just have to wait and see.