Cam and valvetrain longevity....??? low duration high lift...
sorry for your continuing losses.
09-20-2016, 09:49 PM
#232
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Not the experience I've had. When I was doing some mods a few years ago and was low on flow, Bob sent me all the parts i needed to finish the job and said "you can pay me later". Who does that? Certainly not a guy with bad customer service.
09-20-2016, 09:59 PM
#233
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Originally Posted by Full Force View Post
Maya's gay lol he is a great mechanic that can't even figure out his rpm difference issue..
Maya's gay lol he is a great mechanic that can't even figure out his rpm difference issue..
Gay ? Really ? Name calling......just not right.
09-20-2016, 10:11 PM
#234
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Totally understand what you mean here.
Now, what if a bigger cam than that makes more power at your 5200-6200 ? Even though hpkeeps rising even further past the other cam that builds power past where it will be run WOT ?
Where do you stop with going larger ? If it keeps making more power where you want it ?
It's a good discussion what you brought up.
Now, what if a bigger cam than that makes more power at your 5200-6200 ? Even though hpkeeps rising even further past the other cam that builds power past where it will be run WOT ?
Where do you stop with going larger ? If it keeps making more power where you want it ?
It's a good discussion what you brought up.
Heres a build. 555ci. Jesel valvetrain, speedmaster drives, going in a fast twin engine light vee bottom. The original , custom spec'd MK cam, was yanked out, after the combo simply wasn't anywhere near the 750HP goal, (he spec'd heads, intake as well). After days of tuning and trying every trick in the book, it was time to yank the cam. What went in, was a howards nitrous 267/279 solid roller, in its place. Lift was virtually the same. As you can see, there was a loss of torque in the midrange with the larger cam. This graph was prior to any significant fuel and timing tuning, pretty much first pull out of the box. That gap , or loss of midrange, ultimately was narrowed to about a 12ft lb torque loss there. The new cam, ended up making over 40HP more in the upper rpm's. Engine idled well with it. Keep in mind, this cam was a cam sitting on the shelf in the shop, not a cam that took months to spec out for that particular build.
Anyhow, the Green line, is the bigger cams HP, red line, the MK cam's HP. The dark blue line, was the bigger cams torque, light blue, the smaller cams torque.
Even if , we forget about the entire concept of HP and its mathmatical equation for a second, can anyone here tell me, at wide open throttle, say anywhere from 5200 to 6500, why the smaller cam, would pull better? Its clear here, that torque wise, the larger cam, is making more torque, from 5200 RPM and up. Now, if a guy was building a 5200RPM max engine, well, than the scenerio changes. That wasn't what this build was. Even though the MK cam peaked at 6200, the bigger cam was still making more torque at 6200 ( as well as HP, thats how it works), which one you think is gonna pull the prop harder at 6000? Going larger on a cam, and seeing the power hang on longer/higher, than the "RPM GOAL", doesn't always mean the cams "too big". I simply want the most power I can get at wot. In this case, 40+HP , a bunch of upper RPM torque, was well worth losing 12 ft lbs between 4000 and 5000.
Anyhow, the Green line, is the bigger cams HP, red line, the MK cam's HP. The dark blue line, was the bigger cams torque, light blue, the smaller cams torque.
Even if , we forget about the entire concept of HP and its mathmatical equation for a second, can anyone here tell me, at wide open throttle, say anywhere from 5200 to 6500, why the smaller cam, would pull better? Its clear here, that torque wise, the larger cam, is making more torque, from 5200 RPM and up. Now, if a guy was building a 5200RPM max engine, well, than the scenerio changes. That wasn't what this build was. Even though the MK cam peaked at 6200, the bigger cam was still making more torque at 6200 ( as well as HP, thats how it works), which one you think is gonna pull the prop harder at 6000? Going larger on a cam, and seeing the power hang on longer/higher, than the "RPM GOAL", doesn't always mean the cams "too big". I simply want the most power I can get at wot. In this case, 40+HP , a bunch of upper RPM torque, was well worth losing 12 ft lbs between 4000 and 5000.
09-20-2016, 10:15 PM
#235
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Your way behind on this subject bud :-) Here's some cliff notes these are just the tip of the iceberg.
Bob has always been over rated especially on this site, misrepresented what marine Kinetics is actually capable of. Even his own website completely misrepresents his company.
Google earth his "shop" and be awed by a kitchen table and a lawnmower shed out back....
It takes years to prove reliability, or unreliability......
Bob threatens customers who dare speak out giving him a "bad review".....
There are at least 3 well known and respected engines builders that have quit using him, that used to rave about him, and many more builders "names dropped" that never actually used him like he told people....
He tries to guilt people with his family situation which has nothing to do with business
Half his sales are only due to "financing" his customers....
Dozens of unhappy customers including myself, I'm thankful I figured out the truth BEFORE finishing my build.
Happy to hear good reviews, of coarse there's some, but please respect those of us who give him a bad review, so others reading can make their own decisions. If someone chooses to use Bob that's fine, be thankful that we took our time helping others protect themselves from a bad business.
Bob has always been over rated especially on this site, misrepresented what marine Kinetics is actually capable of. Even his own website completely misrepresents his company.
Google earth his "shop" and be awed by a kitchen table and a lawnmower shed out back....
It takes years to prove reliability, or unreliability......
Bob threatens customers who dare speak out giving him a "bad review".....
There are at least 3 well known and respected engines builders that have quit using him, that used to rave about him, and many more builders "names dropped" that never actually used him like he told people....
He tries to guilt people with his family situation which has nothing to do with business
Half his sales are only due to "financing" his customers....
Dozens of unhappy customers including myself, I'm thankful I figured out the truth BEFORE finishing my build.
Happy to hear good reviews, of coarse there's some, but please respect those of us who give him a bad review, so others reading can make their own decisions. If someone chooses to use Bob that's fine, be thankful that we took our time helping others protect themselves from a bad business.
Last edited by offshorexcursion; 09-20-2016 at 10:17 PM.
09-20-2016, 10:36 PM
#236
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evidently somebody is looking to do it otherwise you wouldn't have run the numbers in your simulation software for engine builder. Some of us are just weekend boaters and wouldn't have a problem with tunnel rams or blowers provided height isn't an issue. I would have to assume running a 1,000 hp in a 27 baja you know what I'm saying.
So a point of compression, tunnel ram and dual 1050s was a 69 hp gain. Im pretty sure jimmy v is running a tunnel ram w twin throttle bodys or carbs, 695hp is decent but 765 is pretty strong. Im having fun crunching numbers trying to see what makes real power, Smitty
09-20-2016, 10:41 PM
#237
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Wette Vette's pump gas 598 w/ Dart Tunnel Ram w/twin 1100+cfm Dom's ran 126 mph. Single engine cat w/Bravo.
Also remember, you can spot a Zul motor from a mile away with those having Dart Tunnel Rams.
Also remember, you can spot a Zul motor from a mile away with those having Dart Tunnel Rams.
Last edited by SB; 09-20-2016 at 10:43 PM.
09-20-2016, 10:49 PM
#239
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Wette vette and jimmy v are both friends of mine, the majority of the NA motors you see making 750+hp almost always have what i call "unlimited induction" ie, tunnel rams and multiple carbs or throttle bodys, theres a reason!
09-21-2016, 04:14 AM
#240
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There is some serious "voodoo" in here.... its just a cam. If you monitor your spring pressures you will know if a cam is hard on valve train WAY WAY WAY before there is any damage.
Its really pretty simple. Spring pressure drops 5-10lbs every time you check them? You have an aggressive lobe. Spring pressure is always the same? Everything in your valvetrain is happy.
You dont need to hear what billy or bob ran for x amount of hours.... You just need to pay attention to what is goung on in your engine.
Its really pretty simple. Spring pressure drops 5-10lbs every time you check them? You have an aggressive lobe. Spring pressure is always the same? Everything in your valvetrain is happy.
You dont need to hear what billy or bob ran for x amount of hours.... You just need to pay attention to what is goung on in your engine.
