Building a Sleeper
07-21-2016, 06:37 AM
#202
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07-21-2016, 06:40 AM
#203
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07-21-2016, 06:40 AM
#204
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07-21-2016, 06:48 AM
#205
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[ATTACH=CONFIG]557494[/ATTACH]
Thanks to Bill at Diamond Marine ! Got my bran hammer new headers out to me in record time, so my installer could keep up with the time table we set this week. Chillin tha Most is headed to the SC coast on Saturday morning so Mark at MER Performance can dial in the final tune on the engine.
We should be back in Denver, NC on LKN late Sunday evening just in time for a late run to the 150 Bridge for a cocktail at our favorite watering hole.
9 months, Lots of CC reward points, several trips to Little River, SC, more phone calls than a stock broker, but looks like it all may come together this weekend...................Fingers Crossed!
Thanks to Bill at Diamond Marine ! Got my bran hammer new headers out to me in record time, so my installer could keep up with the time table we set this week. Chillin tha Most is headed to the SC coast on Saturday morning so Mark at MER Performance can dial in the final tune on the engine.
We should be back in Denver, NC on LKN late Sunday evening just in time for a late run to the 150 Bridge for a cocktail at our favorite watering hole.
9 months, Lots of CC reward points, several trips to Little River, SC, more phone calls than a stock broker, but looks like it all may come together this weekend...................Fingers Crossed!
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08-11-2016, 09:24 AM
#209
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UPDATE? Yes it is time for an update, but where to start.........................................
So.............The boat has been at M E R Performance for the last 3 weeks. The main issue in tuning the boat was the O2 sensor was getting wet. NOT at idle, like one would think, but at 2800 RPMs, So tested welds in tails, all good. Welded up end of tails, added second water tap on tails and went with Complete Dry exhaust and added water dumps in swim platform.
Loud as hell and now 02 sensor read very lean condition at 2800 rpms. Lenght of tails and how the KE rectangle flange with 3.78" opening meets the round 4" tail pipe was creating some kind of funkie vortec effect.. Mark changed over to a know longer set of tails that worked on a 555 engine with KE headers (Thanks Yankey!) and the 02 sensor issue has gone away.
Now we are playing the prop shuffle two step game.
The drive on a 252 Formula is normally a Bravo 3 and is deep on the boat. The drive was changed to a bravo one with XR lower, but is still DEEP. A 28P 4 blade Bravo 1 topped out at 4800 on the engine and the boat was loose and squirrey. Mark tried a 29P 3 Blade which improved handling but could only make 4600 RPM on engine. Mark wants the engine up around 5500 to 5700. Looking around for something under 26p in a 3 blade we can test.
Also have a 2" Shorty lower at Bobs in Denver NC we may also test with next week. Just typical fine tuning, but it looks like "Chillin tha Most" will be back on LKN next week just in time for our annual fun run on August 20th. Will post up some GPS speed readings then and let you all know how we finished this project.
So.............The boat has been at M E R Performance for the last 3 weeks. The main issue in tuning the boat was the O2 sensor was getting wet. NOT at idle, like one would think, but at 2800 RPMs, So tested welds in tails, all good. Welded up end of tails, added second water tap on tails and went with Complete Dry exhaust and added water dumps in swim platform.
Loud as hell and now 02 sensor read very lean condition at 2800 rpms. Lenght of tails and how the KE rectangle flange with 3.78" opening meets the round 4" tail pipe was creating some kind of funkie vortec effect.. Mark changed over to a know longer set of tails that worked on a 555 engine with KE headers (Thanks Yankey!) and the 02 sensor issue has gone away.
Now we are playing the prop shuffle two step game.
The drive on a 252 Formula is normally a Bravo 3 and is deep on the boat. The drive was changed to a bravo one with XR lower, but is still DEEP. A 28P 4 blade Bravo 1 topped out at 4800 on the engine and the boat was loose and squirrey. Mark tried a 29P 3 Blade which improved handling but could only make 4600 RPM on engine. Mark wants the engine up around 5500 to 5700. Looking around for something under 26p in a 3 blade we can test.
Also have a 2" Shorty lower at Bobs in Denver NC we may also test with next week. Just typical fine tuning, but it looks like "Chillin tha Most" will be back on LKN next week just in time for our annual fun run on August 20th. Will post up some GPS speed readings then and let you all know how we finished this project.
08-11-2016, 12:11 PM
#210
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Interesting issue on your exhaust, I had the exact same issues with mine from idle to 2200 rpm. I built fully dry pipes with seperate water dumps. I that fixed everything from 1200rpm on up, However below 1200 rpm the exhaust pulses would hit the water behind the boat and it would stir it up and suck it back in getting the O2 wet. So then I also added some drew marine shotgun mufflers onto my dry pipes. The main reason was to disrupt the backwave of the exhaust and keep my O2 sensors dry but also because KE headers with dry pipes are really f$!king loud.Most folks I tell it to don't believe me, and look at me like I'm crazy. Good luck with your project sounds like a lot of fun,
