Question for those who have used Speedmaster assembled heads or valve springs

-
mshred

mshred

The Green Manalishi
Joined
May 2, 2008
Messages
3,269
Reaction score
157
Wondering if anybody on here has ran these Speedmaster heads

Mopar Chrysler SB 318 360 170cc 65cc Hydraulic Flat Assembled Cylinder Heads

or these valvesprings they sell (these are the ones loaded on the heads that come assembled in the link above)

1.450" Od. Dual Valve Springs w/Damper - 145Lbs @ 1.900" - 1.150" Coil Bind

I am asking as I am getting a cam spec'd by Oregon (they are regrinding my old Crane hydraulic flat tappet into a solid flat tappet) and Ken recommends less spring pressure for the solid flat tappet than what I told him the valvesprings supposedly have- 120lbs closed and 300lbs opened, versus the 145lbs closed and 360lbs opened as spec'd in the listing for the Speedmaster heads. I don't physically have the heads in my hands yet, but from what I imagine, they are shimmed to get that pressure with a 1.9" installed height as listed. Has anybody ran these speed master springs with a solid flat tappet under .525" of lift or tested the pressures of these springs? Are they lower in pressure than Speedmaster advertises? I was hoping to run these heads assembled (so long as they checked out) with the parts they come loaded with, but I don't want to put unnecessary stress on the valvetrain in the process after I am finished break in with the inner spring removed.

Any experience with these is appreciated!
 
I run at least 140 lbs on my Street Cars that have solids and 350 lbs open
with no issues for the last 60 years. More on my Race Cars than that.
However, I do NOT let my car idle for any extended period of time ever =
Just shut them off if more than a minute or two.
However, I use quality CWC cast camshafts and not the new Chinese junk!
 
GTX JOHN said:
I run at least 140 lbs on my Street Cars that have solids and 350 lbs open
with no issues for the last 60 years. More on my Race Cars than that.
However, I do NOT let my car idle for any extended period of time ever =
Just shut them off if more than a minute or two.
However, I use quality CWC cast camshafts and not the new Chinese junk!
Click to expand...
What is CWC cast camshaft?
 
There is a you tube video that explains the CWC cams are made in Detroit, and really aren't the problem cams. They did a hardness test and they proved to be very good.
 
GTX JOHN said:
I run at least 140 lbs on my Street Cars that have solids and 350 lbs open
with no issues for the last 60 years. More on my Race Cars than that.
However, I do NOT let my car idle for any extended period of time ever =
Just shut them off if more than a minute or two.
However, I use quality CWC cast camshafts and not the new Chinese junk!
Click to expand...
Well this is not something that I am going to be shutting down during idling. Are you just trying to avoid valvetrain wear? Or is it because the pressures of the valvesprings are actually too much for what youre doing?

As far as the cam goes, the cam im sending for regrind is an 90s crane grind, so im thinking im good on the quality end of things in regards to the core.
pittsburghracer said:
I never ran a set but there’s about three days of reading in the speedmaster sticky post.
Click to expand...
Yea im trying to avoid going near any of that as a lot of those threads are conversation back and forth not really pertaining to the topic and take an eternity to find info lol.

I know you had mentioned before that you had a set of the assembled hydraulic roller heads for a customer, did iu by chance test the springs? Were they pretty close to the advertised specs for them?
 
mshred said:
Well this is not something that I am going to be shutting down during idling. Are you just trying to avoid valvetrain wear? Or is it because the pressures of the valvesprings are actually too much for what youre doing?

As far as the cam goes, the cam im sending for regrind is an 90s crane grind, so im thinking im good on the quality end of things in regards to the core.

Yea im trying to avoid going near any of that as a lot of those threads are conversation back and forth not really pertaining to the topic and take an eternity to find info lol.

I know you had mentioned before that you had a set of the assembled hydraulic roller heads for a customer, did iu by chance test the springs? Were they pretty close to the advertised specs for them?
Click to expand...

I never test the pressure as delivered because I set them up as per customer’s wishes. I think it was JPar that said they were on the light side of advertised pressure. I’ll be tearing down a set of hydraulic roller spring heads today and I wish I could take the time to check some for you but doing it right involves measuring spring heights then pressure and I’m so backed up with work I can’t take that much time. I do know the last set I tore down had six hardened thin shims under the springs.
 
While I would happily buy Chinese made cyl heads, I would buy them bare. I would not trust their springs...or valves. These two components are under tremendous stress & it is most important to use known, quality parts. If they fail, they can do a LOT of damage.
Agree with Ken, 120 lb on the seat, 300 open, less than 0.525" lift should be ok. 145 lb on the seat is getting into roller cam territory.
 
pittsburghracer said:
I never test the pressure as delivered because I set them up as per customer’s wishes. I think it was JPar that said they were on the light side of advertised pressure. I’ll be tearing down a set of hydraulic roller spring heads today and I wish I could take the time to check some for you but doing it right involves measuring spring heights then pressure and I’m so backed up with work I can’t take that much time. I do know the last set I tore down had six hardened thin shims under the springs.
Click to expand...
All good man. I guess I will just have to test them when I have them in my hands.
Bewy said:
While I would happily buy Chinese made cyl heads, I would buy them bare. I would not trust their springs...or valves. These two components are under tremendous stress & it is most important to use known, quality parts. If they fail, they can do a LOT of damage.
Agree with Ken, 120 lb on the seat, 300 open, less than 0.525" lift should be ok. 145 lb on the seat is getting into roller cam territory.
Click to expand...
Cool
 
Bewy said:
While I would happily buy Chinese made cyl heads, I would buy them bare. I would not trust their springs...or valves. These two components are under tremendous stress & it is most important to use known, quality parts. If they fail, they can do a LOT of damage.
Agree with Ken, 120 lb on the seat, 300 open, less than 0.525" lift should be ok. 145 lb on the seat is getting into roller cam territory.
Click to expand...

I run 145-148 on my flat tappet cam.
most mechanical Roller cams I have every run are well over 200 on the seat
 
B3422w5 said:
I run 145-148 on my flat tappet cam.
most mechanical Roller cams I have every run are well over 200 on the seat
Click to expand...

Yes, exactly. In my experience, I thought 130-140 on the seat was standard for solid flat tappet stuff
 
Under Pressure: The Importance of Getting the Right Amount of Spring Pressure - Engine Builder Magazine

IMG_0874.jpeg
 
Toss the supplied springs and use what is recommended to go with your cam. The springs supplied with my heads were way, way too heavy for a small flat tappet cam (XE268).
 
70coupe said:
Toss the supplied springs and use what is recommended to go with your cam. The springs supplied with my heads were way, way too heavy for a small flat tappet cam (XE268).
Click to expand...
And they would be.
 
You must log in or register to reply here.
-

Back
Top