Target Air Fuel ration N/A engines.?
11-07-2016 | 09:24 PM
#131
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Joined: Feb 2009
Posts: 8,356
Likes: 1,515
From: NW Michigan
We shut the port engine down and idled the last short distance to the dock. Per the engine builders request, we pulled the #3 & #6 plug and sent him a picture of each plug. His comment was they were perfect. Also we have zero soot on the transom. Much of the credit goes to the 1150 CFM Holley Marine Dominators. We quit bothering with the AFR meter as these carbs are spot on out of the box. We now also just touch the key to fire the engines and we can now idle at less that 500 RPM in gear. Docking is easy without stalling and not touching the throttles. Not bad for 500 ci 9.5 to motors making 780 HP. Only took us 20 yrs to find the right high HP combination that works in a pleasure boat.
11-07-2016 | 09:34 PM
#132
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Joined: Nov 2004
Posts: 14,100
Likes: 3,687
From: On A Dirt Floor
I thought you where using the newer Ultra Dominators Gen 3's ?
Are they the 2 circuit 0-80905HB ?
https://www.holley.com/products/fuel...arts/0-80905HB
Are they the 2 circuit 0-80905HB ?
https://www.holley.com/products/fuel...arts/0-80905HB
Last edited by SB; 11-07-2016 at 09:42 PM.
11-07-2016 | 09:59 PM
#133
Platinum Member
Joined: Dec 2002
Posts: 2,195
Likes: 2
From: Dallas, TX
Here are the carbs we are using and they were purchased at Jeg's in 2013. These carbs were not officially "Marine USCG" but we did buy and install the Holley J-tubes. I kind of lost the end of the string on some the newer Holley nomenclature and offerings.
Gen 3 Ultra Dominator 4500 Series Carburetor
1150CFM
2-Circuit
1 x 4 Carb Set-Ups
1.830" Venturii
2.00" Throttle Bore
Black
http://www.jegs.com/i/Holley/510/0-80905BK/10002/-1
Gen 3 Ultra Dominator 4500 Series Carburetor
1150CFM
2-Circuit
1 x 4 Carb Set-Ups
1.830" Venturii
2.00" Throttle Bore
Black
http://www.jegs.com/i/Holley/510/0-80905BK/10002/-1
Last edited by BenPerfected; 11-08-2016 at 05:40 AM.
11-07-2016 | 10:26 PM
#134
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Joined: Dec 2002
Posts: 2,195
Likes: 2
From: Dallas, TX
6800 rpm, 500 ci w/3.75" stroke. Similar to the APBA Super Cat engines. The bore/stroke ratios are the same as the SBC. The HP is limited by the 9.5 to CR but they run great on premium pump gas.
Last edited by BenPerfected; 11-08-2016 at 05:43 AM.
11-10-2016 | 08:28 AM
#135
Frank's Marine Service
Joined: Sep 2002
Posts: 11,959
Likes: 142
From: Elkton, MD
Hard to tell from the pic. There should be a heat mark on the grounding strap which I cant see. Would need to see how far back the heat mark is from the tip.
11-10-2016 | 08:32 AM
#136
Frank's Marine Service
Joined: Sep 2002
Posts: 11,959
Likes: 142
From: Elkton, MD
For me cruise RPM is anywhere between 3300-3800. 3300 is low 50's and 3800 is 62-64mph depending on fuel load.
I don't cruise at 4K+ because I start seeing boost right around there. 3800 is around zero and the boat is running a good number. Above that and into boost (1-3 psi), it starts sucking down fuel and for me it's not worth cruising at 4K+.
I don't cruise at 4K+ because I start seeing boost right around there. 3800 is around zero and the boat is running a good number. Above that and into boost (1-3 psi), it starts sucking down fuel and for me it's not worth cruising at 4K+.
11-11-2016 | 02:41 PM
#137
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Joined: Feb 2009
Posts: 8,356
Likes: 1,515
From: NW Michigan
I've always tried to be just up from the bend. I was looking for as well to see how timing was but looks like new plugs and probably 32 deg of timing or less if I had to guess but is difficult to see from angle of pic.
11-11-2016 | 02:49 PM
#138
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Joined: Feb 2009
Posts: 8,356
Likes: 1,515
From: NW Michigan
For me cruise RPM is anywhere between 3300-3800. 3300 is low 50's and 3800 is 62-64mph depending on fuel load.
I don't cruise at 4K+ because I start seeing boost right around there. 3800 is around zero and the boat is running a good number. Above that and into boost (1-3 psi), it starts sucking down fuel and for me it's not worth cruising at 4K+.
I don't cruise at 4K+ because I start seeing boost right around there. 3800 is around zero and the boat is running a good number. Above that and into boost (1-3 psi), it starts sucking down fuel and for me it's not worth cruising at 4K+.
05-16-2017 | 11:02 AM
#140
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Joined: Oct 2013
Posts: 2,888
Likes: 148
From: SF Bay Area
Are the Holley and QF power valves interchangable? I don't want the high flow units that QF makes. Or would you all recommend using the 4 door units and leaning the secondary jets down?
Last edited by Baja Rooster; 05-16-2017 at 11:09 AM.
