ICDEDPPL

iTrader: (1)

First I gotta say thanx for Mild Thunder, for helping to guide me in my Cigarette adventure.
When I got her she was a lazy *****... way too rich, fouling plugs.. (9AFR`s @4000rpms) with secondary powervalves plugged, we took her out on the river for some test and tune.


AFR`s: (great air 65* day)

3500rpm PORT: 12.4
STARBOARD: 13.4

4000rpm: PORT: 11.2
STARBOARD: 12.2 making about 4psi

4500rpm: PORT: 10.8
STARBOARD: 11.3

5000rpm: PORT: 11.1
STARBOARD: 11.1

FULL THROTTLE:
5300rpm: PORT: 10.9
STARBOARD: 10.9 (6.5-7psi)

78MPH on flat water

Any ideas why the STARBOARD is a full point leaner until after 4000rpm??

So I think its a SOLID 80MPH when she gets some air under her..and some more rpm right?? We tried some 4 blades and could not get on plane. Would like to see what it would run at 5600 rpm...

Took her out on the lake and she ran really nice in some chop, really lightened the hull...but with a small craft advisory and a angry Lake Michigan top speed was not in the cards and a dead battery on the Go Pro a nice rough ride was not recorded.


Some videos:

AFR readings, full screen should be able to read the FAST readout


http://33outlaw.zenfolio.com/img/s10...098024-210.mp4

My oil temps are getting up there...hmmmm
Also both #6 plugs tend to be WAY darker looking ????

MILD THUNDER

iTrader: (3)

13 plate coolers and Keith eickert remote oil stats, good water pressure, I think the oil stat is stuck closed, bypassing the cooler. That needs to be addressed asap. Glad I found the issue with the carbs. The way it was setup I think we'd be putting rings in it by the end of the season. Just something that was overlooked.

As far as the starboard carb running leaner at part throttle, I think we may have to look at the power valves in those primaries. I think the main jetting is close now. Things like the PV opening rate, power valve channel restriction size. These carbs were used but rebuilt. Need to really see whats up with them. Could even be one carb having different size air bleeds, etc. We could order 4 new quick fuel 950's and be done

Theres still more work to do. But its coming along. We're moving in the right direction. Boat loves trim. The more trim you gave it the faster it went. In my opinion, I'd leave the drives turning in (bow lift). The fact its running faster with more trim, is telling me it likes more lift. 15 Degree rake 5 blades are lifting the stern whether out or in. I'd love to try some 18 degree rake smaller diameter 5 blade. Then again, im not brett from b blades, and im not Tres martin. Its all trial and error.

These Flatdecks NEED chop. Your easily a 80+ mph boat on the big lake. I just wish I had more free time right now, to really spend some more time with you on it getting it setup. Boat is friggin gorgeous on the water.

Unlimited jd

iTrader: (5)

So how ya gonna change the paint to reflect "80mph"? Lol
Thanks for the info, I'm very interested in the results. What is the effect of changing the rake angle? Stern lift?

kvogt

Call me. Starboard is to lean in the midrange.

MILD THUNDER

iTrader: (3)

[QUOTE=ICDEDPPL;3966662]

Any ideas why the STARBOARD is a full point leaner until after 4000rpm??

QUOTE]

When watching the video, you can see the starboard carb, go from being lean at 13's to low 12's with just a fraction of rpm increase/throttle position. Its like a switch was turned on giving it the extra fuel, and then things evened out. My thought is, those powervalves aren't opening soon enough. Changing main jet will also affect wot. We don't really want to do that. These carbs are not boost referenced. They had 6.5PV's in the rears, which we removed, and my guess is they have 6.5PV's in the primaries. I would like to change them to 8.5PV and retest, to get them to open sooner.

Theoretically, both engines are the same, and both pv's should open at the same time. They work off vacuum signal under the carb. However, They are little spring actuated diaphrams, and not totally perfect in how they react. One prop with a tad more pitch to it, or a tad less trim on that drive, can affect the vacuum/boost level on that engine at part throttle. A tiny difference of 1'' of vacuum at cruise speed, can determine whether the valve opens or closes. In my opinion, going from 13+ AFR, to 12 AFR, within 100-200 rpm change, is not main jet. That's PV opening.

If you had boost referenced carbs, you wouldn't see this. At 3000-3500RPM, or 0" of manifold vacuum, the valves would be open. Actually pretty much anytime your on plane they'd be open, and all your tuning would be on the main circuit.

MILD THUNDER

iTrader: (3)

http://www.youtube.com/watch?v=vpgJViJapeI&feature=youtu.be

MrCIG

iTrader: (1)

Sounds and looks good!!!

My brother in law saw it on Saturday on Harlem and thought it was mine.,my sister figured I took it out and headed south to warmer weather LOL

Mark

mmb

What happened to the engine video??? That was awesome!! How did you mount the GoPro in the hatch?

mike tkach

iTrader: (3)

joe,on non boost referenced carbs i use a 9.5 or 10.5 power valve,i think you are correct in thinking it,s a powervalve issue causing the difference in afr,s at part throttle.

mmb

You can throw power valve numbers around all day long... You wont know what his engine needs till you put a vacuum gauge on it....