Spring pressure for hydraulic roller cam?

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Carnut68

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I considering going to a mild hydraulic roller. Been looking at the Howards grinds. This will be for a 511 RB. Indy EZ heads. My Valve springs are currently set At 155#@1.88 and 360#@1.3. Will these springs work?[Comp928} 10 degree locks.
 
I think u should be good. I would want any more pressure as u may be collapsing the plunger too much with too much spring. What does the cam manufacturer recommend? U should always check with them first. Can ur heads handle the lift u want? Kim
 
Sounds about right. The retrofit hydraulic roller cams need more spring pressure than you would expect for the lift, because of the mass of the lifters. I ended up upgrading to comp beehive springs on my engine.
 
oldkimmer said:
I think u should be good. I would want any more pressure as u may be collapsing the plunger too much with too much spring. What does the cam manufacturer recommend? U should always check with them first. Can ur heads handle the lift u want? Kim
Click to expand...
My heads are capable. The have been bowl blended and back cut valves and gasket matched. They are Indy EZ. I'm not looking for every ounce of hp @ 511 ci I shouldn't need it. As for the manufacturer I guess I 'll have to call [Howards].If I would have to change the springs I would most likely go solid roller.
 
The cam profile, rocker ratio, valvetrain weight, and rpm requirement are all things that need to be considered when trying to determine what springs should be used in a given combo.

Are there HR cams that will work satisfactorily with a Comp 928 in a BB Mopar?
Of course.
 
PRH said:
The cam profile, rocker ratio, valvetrain weight, and rpm requirement are all things that need to be considered when trying to determine what springs should be used in a given combo.

Are there HR cams that will work satisfactorily with a Comp 928 in a BB Mopar?
Of course.
Click to expand...
I'm looking at these 2 Howards cams 723445-10 235/241 @50 545/545 on 106. 723235-12 243/247 @50 600/600. on 108. My springs are set @155@ 1.88-1.89. 360@1.3. My new build is pump gas 511 RB shooting for about 10.3-4/1 comp. I have EZ heads standard port. PRH valve job w/back cut valves, blended, ported chambers. I have 3 choices of intakes M/1, Torker II, TM7. I'm not looking to squeeze every ounce of hp just easy on parts and low maintenence. Too many horror stories about flat cams that's why I'm thinking about going roller. I could go old school and throw the MP .557 I have that's already broke in.
 
If you’re considering one of those cams, you should see what they recommend for spring load, and see how close what you have is, compared to their recommendation.

They will certainly work up to some rpm point.
Then the question becomes do the springs have enough load to allow the motor to achieve a high enough rpm to find the limit of the lifters?
Or, high enough to where you’ve reached your own predetermined limit.
 
If I didn't screw up something the stock 360 Magnum springs are:
  • 1.640" Installed Height @136 lbs
  • 1.150" (0.500" valve lift) @329 lbs
I'm thinking that if this is adequate for a stock roller hydraulic, an aftermarket may need a bit more due to more lifter weight.
 
6PakBee said:
If I didn't screw up something the stock 360 Magnum springs are:
  • 1.640" Installed Height @136 lbs
  • 1.150" (0.500" valve lift) @329 lbs
I'm thinking that if this is adequate for a stock roller hydraulic, an aftermarket may need a bit more due to more lifter weight.
Click to expand...
I called Howards and they suggested Lifter Part # 91774 specs for those lifters are 130-180 on the seat no more than 385 open. 7000 max rpm. My springs are 150-155@1.88 seat/360@1.3. Looks like I'm good. I have no intention of winding it to 7000.
 
6PakBee said:
If I didn't screw up something the stock 360 Magnum springs are:
  • 1.640" Installed Height @136 lbs
  • 1.150" (0.500" valve lift) @329 lbs
I'm thinking that if this is adequate for a stock roller hydraulic, an aftermarket may need a bit more due to more lifter weight.
Click to expand...

Those are not stock magnum springs.
 
Carnut68 said:
I called Howards and they suggested Lifter Part # 91774 specs for those lifters are 130-180 on the seat no more than 385 open. 7000 max rpm. My springs are 150-155@1.88 seat/360@1.3. Looks like I'm good. I have no intention of winding it to 7000.
Click to expand...

I tried going the hydraulic roller lifter route on my 493" RB. There is a delicate balancing act between having just the right spring pressure, having too much and having too little. Mopar hydraulic rollers are behind the curve compared to whats available for GM LS engines. I love those Indy EZ's. Mine flowed 345 Intake with a non-Max wedge port. I ended up going to a solid bushed axle roller, and love it.

Those cam specs don't seem optimal for a motor you are not going to rev that high. Why not consult a cam guru like Dwayne Porter?
 
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