Cam-shaft

190 over the nose on a hydraulic roller that is running only 6000rpms is a little much for sure. Yes a lot of guys run this kind of seat pressure with similiar set ups and it is not needed. However, this is only my opinion. I would agree that comp lifters for sure are not the greatest. I have seen more then one box of hydraulic rollers not make it past my pre-inspection. Example: The locks that hold the roller pin in were half in. Some had two locks on one side of the pin. The roller had some serious drag. These are just some things I found with comp lifters and yes I sent them back and bought a better product.

MESABALANCING

I'm sorry I didn't answer sooner I hadn't seen the post I made a commitment last year that every one of my Top Gun Series Poker Run engines we build from that point on would have Jesel Rocker assemblies in them . Reason for that was that everything that is just fine for a marine engine is sooner or later subject to failure and I can tell you from experience that 95 % of failures in a marine engine are in the valve train when it's not a catastrophe damage . You can break a Jesel part and we have in the past but as far as perfection in geometry and longevity there is nothing you can compare it to aside from one of the other shaft rocker companies such as T&D which is also to of the line stuff. I saw someone say to use the Sportsman Series but for three hundred bucks or so more I would use the better stuff it's worth every bit of it. Sincerely Laz www.mesabalancing.com
P.S.have a great thanks giving guys

mrhorsepower1

[COLOR=Navy][I] The Jesel shaft system is hands down the best on the market. I use them all of our SuperCharged engines as well as N/A applications. We have raced them in many classes such as Modified,A,B,and Super V running 6800-7600 RPM over the years- reliability is second to none! If you can afford them buy em'. I agree with Mesa, spend the extra bucks and invest in the competition series.

Best Regards,

Dean Gellner
Gellner Engineering Custom Marine Engines
"The House of Horsepower"

articfriends

Sounds like alot of pressure but my reasoning was this: If springs are installed at 190 psi and lose 5% of there tension during breakin they actually end up closer to 180 psi seat/430 open. At 5800 to sometimes 6000 rpm's with my pump gas pulley on the supercharger I'm seeing at least 10 psi of boost,on race gas the boost may be as high as 14 psi,when you add in the force of the boost lifting the intake valve off the seat,you need to factor in another 20-40 psi of spring pressure. If it takes a valve spring with 160 psi seat/380 open to keep a hydraulic roller lifter in contact with the cam and the valve from bouncing off the seat at 6000 rpm's with a very slight safety margin and you add the extra pressure to compensate for the boost trying to push valve open prematurely then you'll see where I arrived at the pressure I'm running.The morel lifters I'm running don't seem to have any problem at these pressures either although Ive also ran comp cams hyd roller lifters at similar spring pressures without lifter failure in 140 hours between freshening,Smitty

GPM

I agree, I've had more problems with not enough spring pressure vs to much.

RedDog382

Pics:

RedDog382

Another:

GPM

That doesn't look good, what kind of spring pressure? what heads?

RedDog382

These are CNC ported Dart heads. Not sure what the spring pressures are ... I will see if I can get that info. Sterling says they have seen this before.

Vinny P

Smitty,
I am running the same lifters in my NA 540. I have an Isky hydraulic roller, Isly silicon springs with AFR 315 CNC heads. I set the spring pressure to 140 lbs. as per Isky's recommendation. I understand your reasons for running 190 lbs on the seat. I just never heard of that much pressure on a hydraulic lifter. That is good news to me. It gives me confidence in the Morel lifters.

Vinny