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Discussion Starter · #1 ·
Well I got the bike dyno tuned today. The dynamometer says I picked up a few horses and torque. The butt dyno feels like I picked up a lot more.

Back when the bike had the .203 cams and OEM heads, on the same dyno with the same tuner, it produced 78.02HP, and 94.48 peak torque at 3,800rpm. Today I took the bike back in after the installation of the AMS heads, and Andrews 26G cams. On its first untuned run, (blue run file on the dyno sheet), it was lean and produced 79.74HP and 87.76 peak torque at 3,800rpms. After it was mapped and tuned, (red run file on the dyno sheet), it produced 83.69HP, and 92.45 peak torque. The difference, is that the torque peaked at 3,100rpm and stayed pretty much level to 4000rpm, my ideal riding range.

Click on this link for a picture of the dyno chart: http://i35.photobucket.com/albums/d168/noquestionmark/Motorcycle/HDDyno.jpg

On the street this translates to good freeway roll on to pass cars and trucks. It has a lot more low end, and pulls hard all the way to redline. Furthermore, the torque came on right about 2,000rpms, which felt almost instantaneous to me. Overall the bike just ran better. It idled smoother and ran smoother. It was faster.

Other than the AMS heads and Andrews 26G cam, the only other changes I have made was swapping out the Hooker Tuned Flow mufflers for quieter FullSac mufflers, and a new SE air cleaner element. I also had the pipes JetCoated to cut down on heat. I’m sure I might have gotten higher numbers if I put in fresh plugs and indexed them, and checked my tire pressure.

If you click on these links and take a look at my OEM heads, you will see that the exhaust valve and exhaust port are white from excessive heat.
http://i35.photobucket.com/albums/d168/noquestionmark/Stockhead.jpg
http://i35.photobucket.com/albums/d168/noquestionmark/Stockheadexhaust.jpg

Although the temps were cool for Los Angeles, 65-70 degrees, the bike ran cooler than usual. My Roger McQuen oil temp gauge read a steady 180, even on the dyno. The infrared thermometer read head temps between 275 – 325 degrees during various stages of the tune. I believe the lower engine temps were a result of the AMS heads with the coated exhaust ports, and the thicker Cometic head gasket which brought the compression from 10.25 to 1 down to 9.3 to 1. I am optimistic that I have gotten rid of hot engine knock.

I am pleased with these results. I should have done this long ago.
I see a six speed gear set in my future.
 

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Paniolo,

Was looking at your Dyno and am happy for you and I, as this is the same build as I am gonna do the first of the year. Have the parts in hand from Steve, the torque is what I am looking for in this particular range. Mahalo for sharing....

Randy
 

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Discussion Starter · #7 ·
XLCH74 said:
How were the AMS heads configured... ...looks like 85 cc? ...valve size stock or larger?
The heads on my bike are cc'd at 86. This was done to work in conjuction with my existing SE 95" flat top pistons, the Andrews 26 Gear Cam, and an .043 Cometic headgasket.The valves are stock size, but they are cut and faced differently to help flow. AMS took all of this into consideration when putting my package together. You can check this all out at: http://www.automotivemachine.com/

Mark
 

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Thanks Mark - looks like a nice setup. I checked out AMS's site & will be getting in touch with them for more info. ...have been doing some web-surfing on their work today - appears that they like to stay conservative on their CR's - probably a reliability focus.
 

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AMS will work with you

AMS will work with you on CR. Ask them to make your CR 9.8 with a 37 and they will. They will advise you against it. They try to make builds super reliable for all parts of the country, even where there is bad gas.

David
 

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Discussion Starter · #12 ·
marshrat said:
I've been looking at World Thunder Empire's Alpha-N fuel processor. Wouldn't this unit make dyno tuning unnecessary?
Well while one would think that from all the advertising, however, that has not been my experience.

It is designed to manipulate small changes in the fuel system, the type that you would encounter going to different altitudes, or running under loads. When the O2 sensor picks up a change in the exhaust gasses, it sends signals to the ECM to make minor adjustments as needed. Where as the open loop system relies on engine sensors, these units read the exhaust gasses and the processor provides this information to the ECM to make more efficient adjustments. My finding is that is designed to adapt to minor engine modifications such exhaust systems, downloads and intakes. Those changes affect the tune. It cannot adjust for wholesale major engine changes such as pistons, juggs, heads, and cams.

I had Gary (the guy who invented them) install one on my bike when he did my SERT dyno tune. I was hoping the dyno tune and the fuel processor would get rid of the heat induced ping that has always plagued my bike. As I left, I told him that if my bike continued to knock, I was considering heads and a cam. I asked him if the bike would need to be dyno tuned after getting the heads and cam done. He said maybe not, but to let him check the tune after I got the work done.

Well Garys tune was excellent, but it was not the cure for my problems. As soon as the hot weather came back and the engine became heat soaked, it started pinging again. Soon afterwards the heads and cams went on, I rode the bike a while and it ran good. Better than ever before actually, and with no ping. I probably could have continued to ride the bike that way with no problem, but I took it back to Gary to have him check the tune anyway. On the first dyno run he could see that the MAP needed some tweaking. Afterward tweaking it some, the bike gained a few more HP and TQ. More importantly, it ran a lot better. In fact it runs so good now it scares me, I keep waiting for the other shoe to drop.

The unit about 50 miles to "learn" how your bike runs, in order to make the optimum adjustments, and it is continually doing so. I would not say it is self tuning in the literal sense of changing the MAP timing and wholesale fuel settings. I would say it adjusts the current state of tune for optimum operation, i.e. going up a hill into the wind, add a little fuel. Going down a hill, remove fuel. Up at 7,000 feet, remove fuel. It does what it can to keep the ECM at that ideal stoichometirc 13.5 afr setting.

I guess what I am saying is that although the fuel processor does an excellent job of compensating for changes, in my experience, it is not a replacement for a dead on dyno tune.

Your mileage may vary.

Mark
 
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