Cam and valvetrain longevity....??? low duration high lift...
#1372
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Did you try tuning out that dip in torque at 3400?
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.
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.
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#1374
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As far as making more power, I think what I got from these heads is decent. I have no opinion on the 112 lsa. Someone else can spend a few days on a dyno swapping cams, checking for reversion, idle quality, powerbands, peaks etc. and post the results. I think my new philosophy is going to be, if I don't see it on a dyno it doesn't exist. If I change any component on an engine to make more power I'm automatically adding $600 and a day on a dyno into the equation. Edit- actually I don't think I'm really interested in making changes or being involved with a build again based on my past experience. I think I'll just write a check to Innovation Marine and let an engine show up and if that doesn't work I'll leave the sport. As far as hands on engine work goes I have yet to meet anyone in this industry that I'd ever go back to and I don't have unlimited funds to find a new builder to spend thousands of dollars with every year or two .
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Last edited by bck; 10-08-2016 at 10:10 AM.
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#1375
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see the
,,I was making a funny.I use cams in the 112 range all the time,,unless I'm building a really big cube motor.
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#1376
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Sorry, that's ok. Whether kidding or not that's still my thoughts on the whole thing. But it does get tiring hearing what people think should have been done after the fact.
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#1377
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Me too lol and that 5 minute 4200 run we did lol
Did you try tuning out that dip in torque at 3400?
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.
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.
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#1378
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We can agree there no doubt, if I listened o a select few I would have been in a better place but most came up after I was done shopping, oh well ..hoping this is my last round, as far as trusting? Well the best can have issues so I guess I am ok with learning and building mine...
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I see that MK was spec'ing high lift short duration for pretty much everything. So what is the theororetical value of such relative short duration? I'm flipping through a comp cams catalog and all of their cams for marine use ~.550 lift but about +20* on the duration. These seem flat and wide compared to the MK cams.
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