Cam and valvetrain longevity....??? low duration high lift...
10-07-2016 | 04:55 PM
#1361
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From: taxachusetts
Nice to see someone finally put some cam in an engine. These. 240* 540s are a dime a dozen .
That is a big port, prob wouldnt go that route for an NA 540 marine build, the 320 darts would prob work better. But with that roots up top, low end shouldn't be an issue. Im sure yours made plenty of torque.
That is a big port, prob wouldnt go that route for an NA 540 marine build, the 320 darts would prob work better. But with that roots up top, low end shouldn't be an issue. Im sure yours made plenty of torque.
10-07-2016 | 05:21 PM
#1362
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From: Olmsted Falls,Ohio Marblehead,Oh
10-07-2016 | 05:44 PM
#1363
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From: taxachusetts
10-07-2016 | 06:19 PM
#1364
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That looks like a happy engine and must pull really hard with the one inch spacer. Pretty hard to find anything bad with your combo and you certainly did a lot of testing with intakes and carbs to get solid information.
10-07-2016 | 06:39 PM
#1365
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Not a huge difference but it averaged 4 more ft/lbs and 10 more hp with the 1 in. Peak tq was up 7 ft/lbs. The 2 in. only outperformed the 1 in. the last couple hundred rpm. The 1 in. also brought the peak hp rpm down a little and peak tq rpm up a little.
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Straight bottoms and flat decks
Straight bottoms and flat decks
Last edited by bck; 10-07-2016 at 06:42 PM.
10-07-2016 | 08:17 PM
#1367
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I just put a couple more charts up with the different combos on the thread I started about the intakes so as not to sidetrack this one.
http://www.offshoreonly.com/forums/g...take-info.html
http://www.offshoreonly.com/forums/g...take-info.html
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Straight bottoms and flat decks
Straight bottoms and flat decks
Last edited by bck; 10-07-2016 at 08:20 PM.
10-07-2016 | 08:46 PM
#1368
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From: Olmsted Falls,Ohio Marblehead,Oh
10-07-2016 | 10:11 PM
#1369
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I remember seeing a video you had posted of one of your dyno pulls. Im no dyno expert, but that was like the fastest dyno pull i had ever seen. What was the sweep rate ? If i recall , seemed like it rev'd from 3000 to 6000 in like a few seconds.
On mine , it was the opposite. 3000-6500rpm took a long time. Wanna say it was like 150rpm per second sweep. I found it quite nerve racking loading the engine that long and hard. My engines would never accelerate that slow in the boat.
10-07-2016 | 10:36 PM
#1370
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I just put a couple more charts up with the different combos on the thread I started about the intakes so as not to sidetrack this one.
http://www.offshoreonly.com/forums/g...take-info.html
http://www.offshoreonly.com/forums/g...take-info.html
