Re: Dyno Run

Sheep <d.l.dubose@xxxxxxxxxxxxx> sed:

On Mon, 29 May 2006 02:14:58 GMT, Chilly wrote:

Shirley a round is in order.

The night I got to Daytona, I made my appointment with Dr Dyno and he
tuned the PCIII USB on my 04 FLHTCI with stock headers, Khrome Werks
HP+ slip- ons, Snarl's Heavy Breather and stock cams. Got an ok
torque curve that came on slow and peaked at 78.44 ft/lbs at 3800 rpm.
The next morning, on my way to Smiley's, I was hit, and the cager's
point of contact was the PCIII!

While the bike was in the shop, I figured a 95ci upgrade, 204 cams,
and V&H True Dual Headers might just help to alleviate my pain &
sufferin'. She ran pretty good, but I never had her dyno-tuned. I
took her to Al's American Iron outside of Grand Rapids - an offishul
Power Commander Tuning Center. Al took two hours to tweak it and got
me 91 ft lbs right at 3200.

http://webpages.charter.net/bghouse/Chilly/Photos/bagrdyno.GIF

I was concerned that eliminating the exhaust crossover was gonna cause
a dip in the tq curve, but it comes on quick, there's a very slight
dip around 3800 and then she slowly looses steam from 4000 on.
Air/fuel is a little lean at cruising rpms, and is richer from 3200
on. The tuning provided a noticable seat of the pants improvement,
and we'll see what kinda milage I get next weekend.

I agree with Roger. Torque looks good but the HP seems low for what
you have. Not sure why though.

Yeah, I see stage II type installations with peak hp at ~82. On mine,
the torque peaks early, then starts dropping off. Since HP is a
mathematecal computation based on torque, and torque is down around 70 ft
lbs at those higher rpms, that would account for low hp numbers. I see
other dyno charts, including those in the SE catalogue, showing torque
peaking much later, and that would help boost hp numbers.

I'm much more interested in maxing torque at lower rpms and I like the
general shape of the curve - Though I'd like it better if tq got up to
the low 90s and stayed there across the page <g>. So, is it dropping off
too fast, too early? If so, maybe the pipes? I don't think anyone who
puts true duals on a bagger is thinking of performance first. Mostly
folks want to get that bum warmer out of there. Those headers ain't
fancy designs with steps to provide back-preasure. Maybe the cam? Maybe
it's the combo of the cam and the pipes? He said he noticed reversions
at specific rpms, and had to tweak some to flatten the curve at those
points. Maybe 2=>1's would open her up better ... along with head work
<g>

Whilst pondering these lofty questions, I'll enjoy what I got!


--
Chilly BS#226
.

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