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Cam and valvetrain longevity....??? low duration high lift...

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Cam and valvetrain longevity....??? low duration high lift...

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Old 09-15-2016, 08:36 PM
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Look you have to pull the intakes to get to the lifters, So itsjust as easy to put a blower manifold back on.... then drop the blower on and your golden....
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Old 09-15-2016, 08:38 PM
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Originally Posted by BGIII View Post
If I were you Tim, I would pull engines and change the cams. At least you will sleep at night, even if you were to gain nothing. This stuff is going to put you in the nut house and it's not worth it. You're taking years off your life over a couple grand.
I have a feeling it's not so much the couple of grand more so the extra power and speed gained. However with that said what's that magic cam so it's not all a waste of time and money. I know of a custom grind that I am certain would work well and achieve his goals but would like to see him get his heads flowed to see how close they are to advertised. At least one anyway. More power to be had with those heads.

Last edited by getrdunn; 09-15-2016 at 08:42 PM.
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Old 09-15-2016, 08:40 PM
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Spend what I did, go slower, and add the nonstop worrying.... I have the right to be extremely upset dude...and I am actually looking for a solid answer to fix it
Originally Posted by SB View Post
Do I dare say us too ?
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Old 09-15-2016, 08:43 PM
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Mild has a grind that seemed to really wake it up on the computer, the existing numbers were within a few HP of my dyno sheet, I am going to contact a few to get overall opinions, Dean Gellner just did 540's making 706, I am going to talk to him, and Cam Motion direct, and a few others like Comp, Erson and such...

what is your grind? EVERYONE has so fasr told me I need to be in the 250'[email protected] to start..

Originally Posted by getrdunn View Post
I have a feeling it's not so much the couple of grand more so the extra power and speed gained. However with that said what's that magic cam so it's not all a waste of time and money. I know of a custom grind that I am certain would work well and achieve his goals but would like to see him get his heads flowed to see how close they are to advertised. At least one anyway. More power to be head with those heads.
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Old 09-15-2016, 08:44 PM
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no hatch space for them... pro chargers at a later date, blowers are pointless with TRS and 540;s anyway...

Originally Posted by phragle View Post
Look you have to pull the intakes to get to the lifters, So itsjust as easy to put a blower manifold back on.... then drop the blower on and your golden....
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Old 09-15-2016, 08:48 PM
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Originally Posted by getrdunn View Post
If I recall you were 241/246-670 or so. I may have stated this in one of your other threads however valako runs like something real close 236/244-707 gross lift on the intakes. Custom ground hyd roller and runs solid roller and springs. No issues. Been running that way for years and that lift is with 1.8 rockers. You'd think if any combo would have premature valve train wear or failure that would but seems to be pretty trouble free.
Yikes if HR rollers lifters. Or are you saying solid roller lifters ?
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Old 09-15-2016, 08:59 PM
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Looks like another Cam thread. What most don't realize is when the lift increases on a Lobe , the Duration also has to increase . Because of Valvetrain Stability. The magic bullet , high lift low duration cams, have a built in flaw . There is not enough Duration on the lobe to control bounce and loft. Everyone thinks that a lifter follows the lobe exactly. Not true. You have what is called Loft , at increasing RPM , the Lifter does not want to follow the lobe . Inertia takes over and objects in motion tend to stay in motion.
Thus the lifter jumps the nose of the lobe , and tries to land gracefully on the backside of the lobe. If it lands to far down the lobe , it bounces. Which sets up a Harmonic through the whole Valvetrain , The only solid points to dampen the Oscillations are , the Lifter and Lobe interface , and the Valve to Seat Interface. Resulting in Valves and Valve Seats that have been beaten to **** , Or Lifters that break due to the severe harmonic ( Bounce ) that is placed on them.
I know the theory , and the brain trust , behind the Magic Bullets. Trust me there is no magic bullet. If a name brand cam company doesnt have the lobe
configuration your looking for, There is a good reason why. That Reason is Thousands of Hours , and Millions of Dollars of R&D into Master Cam Lobe developement. That
actually works .
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Old 09-15-2016, 09:01 PM
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Morels are junk. Buy Johnson. Ask me how I know!!!
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Old 09-15-2016, 09:29 PM
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Lifters are always the scape goat for a number of other valvetrain issues I think.
My spring pressures are 218/545 and the standard Morels haven`t failed me in 4 years and this year I`ve run em a little past 6200rpm.
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Old 09-15-2016, 09:32 PM
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Originally Posted by 1MOSES1 View Post
Morels are junk. Buy Johnson. Ask me how I know!!!
I know quite a few guys, including myself, who have been running morels with great sucess. And they arent a basic 600hp build. Talking 800, 900, 1000, and 1200hp engine's that have seen north of 6,000rpm. Icdedpples 900s have some time on those lifters, as have mine. How many hours have you got on the johnsons so far? And whats the cam/spring combo?

I know some have had some issues with them, and some noise issues. I will say this, if you have a hyd lifter capable of 7000rpm and 600lbs over the nose, the clearances are tiny, and very precise in those lifters. They do not tolerate any debris in the oil, and an immaculate engine assembly is imperative.

Mine did have some lifter noise after this springs reassembly. It did however, go away after a little run time. They arent quiet like a stock gm lifter though. But then again, i wouldnt pull my engines to 6500 with a stock gm lifter and 500 plus lbs of open psi , with a blown engine and heavy azz valves..

Not sure if id say they are junk. Outside the oso world, they are still the lifter of choice for a serious bbc build thats needs a hyd lifter capable of rpm. Their lifter bodies and tolerances are far from junk material or machining .

Last edited by MILD THUNDER; 09-15-2016 at 09:35 PM.
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