what's wrong with my 103 build?

[mikestreet]

Performance (90.6 hp/100.3 tq, STD 5, 25 MPG) seems low and would value some insight! Wondering if:

1. I've topped out and
2. if so, what is the constraining factor (lift, pipes, TB, tune) to address for increases w/o changing cam?

DATA: 103" bore, 10.5 COMPRESSION wiseco pistons, woods tw6-6, supertrapp 2:1 w/ 20 discs-closed, SERT, SEAC w/ KN filter, mild head work.

Dyno sheet attached. Thoughts, please!

 

[USMCCWO5]

Mike;

Your numbers look fine except for the 25mpg. Is that your correct gas mileage? What did you do to the heads?

If this didn't cost an arm and leg, I would be very happy. Does it run good? Does it backfire on deceleration?

Do you have the SERT or Screaming Eagle Super Tuner? Not that it matters, just curious.

What is STD 5?

 

[Bud White]

it was hard to read the pic but where is the ATF Ratio Line? I didnt see it that would help to see what gas mileage si poor it look to me like the lines were aweful jumpy smoother arcs

See thsi post and his dyno sheets how much smoother it is .. granted you will get some bumps .. and also see where he has the ATF Ratio sheet

 

[mikestreet]

James,

Got 30 mpg on my latest fill up. Seems to be slowly increasing as the motor breaks in. Did some longer freeway riding on this last tank. It has a SERT, and doesn't pop on deceleration. My understanding is that STD 5 is one of the ways the dyno measurement is adjusted. And 5 is a level of smoothing. Found a good article by drdyno.com in AIM_July06, but can't post it cause I'm a newbie!

Bud,

They didn't give me the AFR graph .. don't know why ...kinda suspicious. I've heard SD Harley's got an old dyno machine.

 

[patrickcarr]

with my stage 1 and se2 slip ons and pcIII om my sg i got 87.4 hp and 96.3 ft/lbs with a very good freind at hd and about 3-4 hours of tuning and about 10 dyno pulls it was done the afr on average for idle to 100% is 12.9 to 1 so if you have cams, head work and other things i think you should find a better tunner:yeahright

 

[Bud White]

James,

Got 30 mpg on my latest fill up. Seems to be slowly increasing as the motor breaks in. Did some longer freeway riding on this last tank. It has a SERT, and doesn't pop on deceleration. My understanding is that STD 5 is one of the ways the dyno measurement is adjusted. And 5 is a level of smoothing. Found a good article by drdyno.com in AIM_July06, but can't post it cause I'm a newbie!

Bud,

They didn't give me the AFR graph .. don't know why ...kinda suspicious. I've heard SD Harley's got an old dyno machine.

even if its a old dyno no point in tuning if they dont have the sniffer

 

[FishHunter]

Me thinks there is more left in that, especially knowing of the low mpg scenario.
If these were carbed builds, most dicussions as this would not occur.

 

[mikestreet]

:bigsmiley30:Update: 5/18/09

Couple of interesting things:

1. Got the dyno chart with the AFR on it. AFR starts at 14.7 at 1700 RPM, crosses below 13.0 at 2500 RPM and crosses below 12.0 at 3300 and stays there unitl it starts rising above 12.0 at 5500 RPM and slowly approaches 13.0 for higher RPM. Will load chart as soon as i get access.

2. Drive belt broke again putting into first from idle, so when having belt replaced, put back the stock transmission pulley (32 tooth) and removed the Andrews 30 tooth with the dakota digital speedo recalibrator. Mileage seems up as its got 124 miles with over a quarter tank of gas left. It's got the 5 gallon tank. Wonder if the recalibrated speedo and mileage were out of synch?

waddya think??

 

[Bud White]

after chatting with both i am finally seeing how this stuff works - it looks complex and it is and the knowledge these guys have is incredible and i will never have this level of knowledge without proper training, i will in the near future be having Docs system installed to replace the SERT as the base maps correct all the basic issues in the ECM

what basic issues with the ecm

 

[Bud White]

I see let us know how ya like it