HD Sreamin Eagle 103 engine build

[MAVERICK]

Mike I purchased a 07 Road Glide with the 96 cubic inch engine. I had the HD shop in Houston, Texas install the Stage 2 103 big bore kit p/n with the SE 255 cams. I am using the D&D 2 into 1 Fat Cat exhaust and the Power Commander 3. I had Carls Speed shop tune the bike during Daytona Bike Week. The bike dynoed 92 HP and 111 ft lbs of torque @ 5300 rpm.

Since then I took the bike back to the HD dealer and had the dealer install the 103+ SE Pro twin cylinder heads p/n 17071-03B which gives a combustion chamber volume of 98ccs. They also installed the 103 forged stroker pistons p/n 22483-04 that have a 10:5 to 1 compression ratio.

The new top end rebuild only has 100 miles on in so far and I am still breaking it in. What kind of performance gains do you think this build will produce. How about HP and Torque? Do you have any thoughts or concearns on the way the engine was built?

Thanks Brett

[Mike]

My only concern would be the 255 cams. Really not taking advantage of the new heads and shutting down power early. last, with that cylinder pressure detonation may be an issue forcing detuning to control. In H-D cams the 257 or 258 are good choices. The guys at Carls are pretty sharp and you may wish to confer with them on cam recommendations from their selection. With a cam change and Carls tune, I would expect 110-120hp/tq.
Mike

[MAVERICK]

Lets start from the begining. I had the HD shop in Houston, Texas install the Stage 2 103 big bore kit p/n with the SE 255 cams. I am using the D&D 2 into 1 Fat Cat exhaust and the Power Commander 3. I had Carls Speed shop tune the bike during Daytona Bike Week. The bike dynoed 92 HP and 111 ft lbs of torque @ 5300 rpm.

I took the bike back to the HD dealer and had the dealer install the 103+ SE Pro twin cylinder heads p/n 17071-03B. They also installed the 103 forged stroker pistons p/n 22483-04 that have a 10:5 to 1 compression ratio.

Then I had the SE-258 cams the 50 mm throttle body and the cone tapered screaming eagle high flow filter assembly installed. Along with bumping the rev limiter up to 6200 rpm.I had the bike dynoed at the Harly shop and I was really disappointed of the results. It went from having 92 hp and 111 ft lbs of torque to 97 ft lbs and 102 ft lbs of torque at the rear wheel. What happened???

The bike runs really good in 1st 2nd 3rd and 4th gear up to the rev limiter. It runs equally well in fifth except right a round 5500 rpm it acts like it hitting the factory rev limiter stumbles a moment or two then continues to 6200 rpm. When you look at the dyno chart their is a small dip in the horsepower and torque.

I took the bike over to another shop where a guy named Wolfgang put the bike through 30 dyno runs and tried to fine tune the bike with the power commander. He checked the compression, the spark plugs,swapped out power commanders and ran the bike with no airfilter. In other words some trouble shooting. Nothing chaged!! He tried to tune the hp and tq dip out mapping the power commander. It runs a little better but I was hoping for better hp and tq numbers.

Any suggestions to get it right???

[Mike]

With the cam and throttle body change I would expect a torque dip to develope but then recover and make even more torque at higher rpm's, plus the added hp. Sounds like a tuning issue. Is the PC being mapping done in advanced mode (assuming USB version) where each cylinder can be independantly tuned? This can really free up hp/tq and is even more true as the combo becomes more radical. It may also be that while tuning with the PC that knock control and "overspeed enriching" are active. These can really destroy hp numbers on the dyno. One of the reasons we like Race Tuner is that it allows these to be monitored and corrected if needed. Last, we run our dynos in 5th gear and use STD corrections and of course results can be different from dyno to dyno. 5th will show higher numbers but also allows for finer tuning. You've got a good combo and it should make the numbers predicted earlier.

Another thought would be to check the crank case oil quantity after a dyno pull. If more than 7oz, you'll be loosing hp. Easily done through the plug on the bottom, rear, right side of the crankcase. Could be that an o-ring got out of place or pinched with the changes.
Mike

[sean fxd]

Does your Carl's dyno sheet say "STD" or "Uncorrected"? I think Carls does their dyno runs 5th gear STD. If your dealer run is 4th gear SAE you would have 6-8 less tq/hp from that alone.

[MAVERICK]

I finally got the stumble worked out. The bike runs great. It seems that to install a custom map using the power commander you cant have the stage 1 download installed. What was happening is the bike had two rev limiter settings. One at 5500 and the other at 6200. As soon as the rpms got to 5500 it stumbled but keep pulling to 6200 rpm. This hinderd the hp and torque. The bike dynoed at 104 hp and 100 ft lbs of torque at the rear wheel with the stock throttle body.