I was requested to post my dyno charts for the SE 255 cam change I did last month.

I had struggled with the decision to do the 103 upgrade (bore my stock cylinders, SE flat head cast pistons and SE 255 cams) or just change cams. The forum was really helpful with discussions on both the 103 and cams. I also called several folks - Bob Woods, GMT, Jamie at FuelMoto, local tuners and others. I received helpful suggestions and opinions from each.

In the end, I made my decision on the type of riding I do and the value/investment. I do about 1/3 of my riding 2-up, don't race, do long and short rides. I wanted a little more umph but wasn't looking for a large change. From all the calls I did, I came to the conclusion that I also needed a good tune after doing the mods.

In the end, I went with the SE 255 cam change only. This was $800 vs about $2K, I didn't need to go thru the break-in period and didn't need compression releases. I wasn't ready to tackle the project on my own, so had HD do the work. The owner had a set of SE 255's that he'd taken out of his 110 that only had 2400 miles so I got them for $115. I had HD put new lifters and oil change at the same time (my bike had 34K miles so I didn't want the old lifters with wear patterns). The owner also cut me a very good deal on the tune.

I'm happy with the results. My 07 Ultra already had Stage I (SE A/C, SE II slip-ons and SERT).

Dropped the bike at HD last night.. they worked on it last night and most of today. Road it home in the rain, so didn't really get a chance to "run" the bike to see how it performed. Hopefully this rain will stop for a day this weekend :-(

The dealer's dyno is a SuperFlow WinDyn (This dyno is generally 10-15% lower than measured on a DynoJet for the same bike). Because of the differences, I had them do a baseline run prior to doing the mods/tune.

The results: Gained 9 ft/lbs TQ and 9 HP over stage 1 (could probably be a little higher with different slip-ons?)

Before mod: HP = 65 @5500 rpm, TQ = 79 @ 3600 rpm (stays above 70 til 4700 rpm)
After mod: HP = 74 @ 5500 rpm, TQ = 88 @ 3200 rpm (stays above 80 til 4700 rpm)

Corrected to the DynoJet, this would be about: HP = 82 and TQ = 97 - this is a little better than I'd hoped for, especially the gains in HP. (second chart shows the HP corrected to 81.6 as it would be on a DynoJet)

I've attached the SuperFlow charts. I think it is a pretty good curve. ATR is at 13.4 until cruise which is set around 14.

First chart is the before and after as measured on the SuperFlo, second chart show the HP on both the SuperFlo and corrected to what it would be on DynoJet.

 

At about $89.oo for each ft. lb. tq. and hp. gain.

 

Nice gain per dollar.

Should ride like a whole different bike.

 

Thanks for the post.

I'm really looking forward to doing this mod, I'm current high bidder on a set of cams that ends today. My mod would be a bit more though I don't have the SE A/C or the SERT yet. Maybe I'll just get the cams now and start getting the rest of the parts together. I do want to have this all done by spring.

George.

 

If they were the ones from Ohio I was watching on ebay, congrats.

 

They were and thanks. I would have rather they were the ones that ended a half hour befor mine that went for $152.00, instead of the $170.00 I paid. Oh well still cheaper than at the dealer.

George.

 

FWIW, changing the lifters was probably unnecessary. These are the same lifters used in modern GM cars and trucks, which often go 100k's of miles without lifter problems. How many of these vehicles have you heard of that've had lifters replaced?

These are numbers you common see on TC96 with only SE255's and Stage 1 mods, so I think you should be happy with the results. I think you would do even better with a different set of slip-ons, or a 2-into-1 system. Just changing to Fuel Moto Jackpot mufflers would likely make a meaningful difference for a relatively low price. Of course, you will probably need to adjust your map if you make that change.

It'll be good to get your first-impressions after a (dry) road test.

 

iclick, thanks for the feedback. Your posts were some of the most compelling reasons for me to go this route.

Lifters: I didn't replace the lifters because I thought they might fail. I'd read on here and talked to professional builders who said that when changing cams, you should change the lifters as well. Evidently this is done with cars as well. The issue is that the lifters/cams wear against each other and can create wear patterns. If replacing new on used, this can cause problems. I had a lot of miles on my bike at 34K. I checked the used SE cams (only 2400 miles on them) and didn't see wear issues with those, but chose the change the lifters to be on the safe side.

Slip ons. Yep, you are probably correct about the old SE slip ons. I think I would get more power gain with Jackpots or Supertrapps. In retrospect, I probably should have got them and then did the mods/tune. Now I'd have to do a retune so probably won't change soon.

Performance. I was probably expecting a little more seat of the pants dyno change. 10% ain't all that much though. I normally don't "get on" the throttle that much, but on the dry test ride, I twisted it a few times. I really felt the difference when accelerating from like 40 mph to 90 mph. Got there really fast! I'm happy with the change whether it's psychological (Milton said it's mostly in the better sound effects than real performance!) or real.

Sound. The SE II's are a loud set up (not offensively loud) and the cams made the just a little louder. I really like the idle, a little more "potato" sound.

103 vs cam change: A 20% change would diffently be felt by the seat of the pants dyno. Yep, that little guy on my shoulder kepts telling me I should have got the 103. I think a lot of it is that one gets caught up in the Forum postings however. You see these great numbers and pretty soon you think you just have to have them. However, the vast majority of Harley riders never go beyound changing A/C and pipes and are very happy with that performance.

My bike runs good (tune/cam mods) and I feel I've done nothing to hurt the reliablity of the bike. I'm going to switch to the Dunlop E3's next spring after I wear out my 402's. I think with these changes, I'll be very happy for the next 80-100K miles. At that time, I may decide to buy a new engine - mo power! But damm it, by that time I'll be too old to use the power :-) Awww to be 20 years younger!

 

I have a pair of cvo-255 cams that were take-offs from my 2010 SE Ultra engine build. Very few miles. I'll being putting them on ebay in a couple days. If someone wants to make an offer before I list them, drop me a PM.

Here's the description from the Racing catalog:

SE-255 CAM KIT

The ultimate in torque cams, this cam offers substantial

increased in low end torque for engines up to 110 cubic
inches with compression ratios up to 10 to 1. The low end
torque increases are great for heavy bikes or for the person
who routinely shifts below 4500 rpm and wants the power
available to pass without downshifting. The cam still makes
peak power above 5000 rpm so people with lighter bikes will
enjoy the torque increases without feeling like the bike runs
out of air at higher engines speeds. These cams are used in
the ’07 and later street legal 1690 Stage II kits and the 110
Stage Kits. Compression releases may be required depending

on displacement and compression ratio.

 

IMO this is a factor on flat-tappet lifters, but not rollers. With the latter you are not rubbing against a surface but rolling over it, and wear is minimal even after long mileage and the wear pattern is not specific to an individual lobe. If you look at a roller cam after many miles you shouldn't see any measurable wear on the cam lobes.

On a flat-tappet cam you should replace the lifters after a cam change, and if you must pull a cam and lifters on a flat-tappet vehicle, when replaced the lifters must be put back in their original positions. With rollers it really doesn't matter.

A friend is a retired Exxon engineer and does race- and vintage-car engine building for kicks and extra money. He's probably the most knowledgeable mechanic I've ever known and when he performed a BB kit (95") on his 2000 EGC with 60k miles on the clock he reused the stock lifters. You didn't do the wrong thing by replacing your lifters, but I just think it is unnecessary in most roller-tappet engines.

I wouldn't change your mufflers unless you're obsessed with making a few more HP/TQ numbers, especially if you're happy with the way they sound.

I'm not a fan of loud exhaust, but stock is too quiet. I have the new-style Jackpots and with the standard baffles are a bit too loud for me. Fuel Moto has just come out with a "quiet baffle" that I will be getting hopefully next week, and Jamie tells me that will make me happy. The tone of the Jackpots was perfect before the cam change, but a side-effect of a performance cam is increased exhaust noise, and that's exactly what I got. I didn't want it and now I'm trying to tone it down a bit.

I've trained myself to be rational about these things...or at least I am some of the time. Yes, the Stage II with 103, flat-top pistons, and 255's makes a wonderful flat TQ curve that I envy, but I don't want to spend the extra $$ and invade the engine further than I already have. I was actually happy with the stock engine with Fuel Moto Stage 1 mods, but felt if I could get ~10% more TQ in the right places for very little money there would be no harm. I achieved that by doing the cam install myself, and I now have plenty of reserve power for my needs. Also, since I don't get into drag-racing with my friends I don't consider bragging rights to be high on my priority list. What I do know is that on a trip to the Smokies last May I was amazed at how well the loaded-down bike pulled up the grades with minimal downshifting, and I don't think I gave the bike more than 1/2-throttle during the entire trip. There is enough power for everything I've encountered so far, so it is doubtful if I'll make any further performance upgrades to this bike.

Well, I have the E3's along with lots of other changes I've made to the bike in three years of ownership, and I think I'm happy with what I have now. Of course I've said that before and made changes the following week, but for now I'm happy. OTOH, my dealer is having a 20%-sale next week, so I may fall off the wagon temporarily. As for growing old its all just a state of mind.