408 hyd roller, too much spring pressure?

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Swede408

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Hi!

I have finished my 360 based 408 stroker with good result so far!
I am however starting to worry about my spring pressure...

The engine is based on a -89 roller 360.
I used stock replacement roller lifters with the stock spider like plate to hold down the "figure 8 shaped" anti rotation plates.
The cam is a Lunati VooDoo 20200712
As far as I can see, this is a cast core cam.
231/239 degrees @0.050"
.535/.550 lift
I checked during installation, and there is a good margin to the "figure 8" plates at max lift.

I use bronze bushed steel 1:1,5 shaft rockers, very similar to Comp cams ultra pro magnum rockers

Lunati recommended a spring kt for the Eddy heads I planned on using. Before I got them I ended up buying Trick flow heads instead.
The spricg choices for the Trick Flow heads ended up being lower than recommended with the 1,46" diameter spring, and a bit over recomended for the 1,55" spring. After recommendation from Trick Flow I went with the 1.55" diameter spring heads, p.n. TFS-61417802-C00.

According to the specs I end up with 138 lbs seat pressure and 369 lbs open pressure (on the exhaust lobes)

- Is this too much for the stock replacement roller lifters?

- Is this too much for the cast core roller cam?

The engine runs great! But the valvetrain noise is a bit more than expected. When starting up, there is a few seconds of rattle befor the lifters fill up. I guess they drain during standstill? I would consider this normal with hydraulic lifters, but I'm surprised what short time is needed for them to drain.

/Magnus

mock up.jpg
 
I don't have the answers for you but if I may ask, what is the brand of rockers you're using?
 
Garrett Ellison said:
Here are some options.
3.9/5.2/5.9 ENGINE - Lifters - HiPoTek
Hughes probably just re-markets these at considerable markup, but here’s what Hughes says.
https://www.hughesengines.com/Index/products.php?browse=search&search=5006&partid=11034
But as far as how safe the stock replacement hydraulic rollers are with high pressure, you shouldn’t have any issues. But Im surprised you’re not having more noise than just on startup.
Click to expand...

I do have a bit of noise even after start up, but not nearly as loud as on startup with some of the lifters drained.
I don't really get what causes this. Is it the check valve in the lifter that can't cope with the pressure, causing the lifter to bottom out?
 
What is the preload set at? That cam is fairly aggressive and the spring pressures are quite a bit higher than stock (not crazy though IMO) but you shouldn’t have any problems with the stock roller lifter. You might have to experiment with different preload settings until they are happy.
 
TT5.9mag said:
What is the preload set at? That cam is fairly aggressive and the spring pressures are quite a bit higher than stock (not crazy though IMO) but you shouldn’t have any problems with the stock roller lifter. You might have to experiment with different preload settings until they are happy.
Click to expand...

Its set about one full turn from zero.
I have read that setting them just a bit from the bottom could be a way
 
Swede408 said:
Its set about one full turn from zero.
I have read that setting them just a bit from the bottom could be a way
Click to expand...
I’d do the exact opposite. Set them just off the retainer clip at first. Like 1/4 turn passed zero lash. But they may like 1/2-3/4 turn best. At least that’s my experience.
 
The spec for most hydraulic rollers is like .030-.090 preload. So they have a pretty large working range.
 
TT5.9mag said:
I’d do the exact opposite. Set them just off the retainer clip at first. Like 1/4 turn passed zero lash. But they may like 1/2-3/4 turn best. At least that’s my experience.
Click to expand...

To clarify: I have them about one turn from zero preload. I haven't tried the other version, to almost bottom the adjustment out. I guess it can make them quieter (?). On the other hand it also makes an eventual "pump up" higher...
 
Swede408 said:
Hi!

I have finished my 360 based 408 stroker with good result so far!
I am however starting to worry about my spring pressure...

The engine is based on a -89 roller 360.
I used stock replacement roller lifters with the stock spider like plate to hold down the "figure 8 shaped" anti rotation plates.
The cam is a Lunati VooDoo 20200712
As far as I can see, this is a cast core cam.
231/239 degrees @0.050"
.535/.550 lift
I checked during installation, and there is a good margin to the "figure 8" plates at max lift.

I use bronze bushed steel 1:1,5 shaft rockers, very similar to Comp cams ultra pro magnum rockers

Lunati recommended a spring kt for the Eddy heads I planned on using. Before I got them I ended up buying Trick flow heads instead.
The spricg choices for the Trick Flow heads ended up being lower than recommended with the 1,46" diameter spring, and a bit over recomended for the 1,55" spring. After recommendation from Trick Flow I went with the 1.55" diameter spring heads, p.n. TFS-61417802-C00.

According to the specs I end up with 138 lbs seat pressure and 369 lbs open pressure (on the exhaust lobes)

- Is this too much for the stock replacement roller lifters?

- Is this too much for the cast core roller cam?

The engine runs great! But the valvetrain noise is a bit more than expected. When starting up, there is a few seconds of rattle befor the lifters fill up. I guess they drain during standstill? I would consider this normal with hydraulic lifters, but I'm surprised what short time is needed for them to drain.

/Magnus

View attachment 1715952500
Click to expand...
It's on the high side for those lifters.
I bet you hear them pump down after down, tick tick tick...one by one...how do I know? Cause I have a bit less seat load on mine @130-135 lbs...but less open than you.
It's been said 130 was about all you want to run on them for seat with an iron core roller with open around 330.
Preload was stated ... up to .090
Should not have ticking on start up.
 
Swede408 said:
To clarify: I have them about one turn from zero preload. I haven't tried the other version, to almost bottom the adjustment out. I guess it can make them quieter (?). On the other hand it also makes an eventual "pump up" higher...
Click to expand...
Don't adj. from the bottom.
 
Did you turn the oil holes in the lifters towards the cam ?? IF not, they'll bleed down and give you all the rattles at start up.
 
MOPAROFFICIAL said:
It's on the high side for those lifters.
I bet you hear them pump down after down, tick tick tick...one by one...how do I know? Cause I have a bit less seat load on mine @130-135 lbs...but less open than you.
It's been said 130 was about all you want to run on them for seat with an iron core roller with open around 330.
Preload was stated ... up to .090
Should not have ticking on start up.
Click to expand...
Might be a loaded question, but… IF a person was to experiment with this lifter, & take the hydraulic insides out and replace with something to make it a solid roller lifter, would that increase the spring loads it would be able to take?
I don’t know how much abuse the roller wheel axle could withstand either, should something like this be attempted…
 
MOPAROFFICIAL said:
It's on the high side for those lifters.
I bet you hear them pump down after down, tick tick tick...one by one...how do I know? Cause I have a bit less seat load on mine @130-135 lbs...but less open than you.
It's been said 130 was about all you want to run on them for seat with an iron core roller with open around 330.
Preload was stated ... up to .090
Should not have ticking on start up.
Click to expand...

Well probably that's the subtle sound remaining after startup.
Would a "slow leakdown" lifter like HGH 5006S Hughes Engines be an upgrade, or are all stock style Magnum lifters limited to around 130/330 lbs?

I notice that Hughes recommends both the stock type HGH5006 and the fast bleed HUG 5007 for springs up to 145/358 lbs (for instance for cam SER7076ALN8).
Wouldn't the fast bleed lifter cause more bottoming out problems? Or perhaps the limitation of the stock lifters are not only in the noise-causing bottoming out?
 
mopardude318 said:
Might be a loaded question, but… IF a person was to experiment with this lifter, & take the hydraulic insides out and replace with something to make it a solid roller lifter, would that increase the spring loads it would be able to take?
I don’t know how much abuse the roller wheel axle could withstand either, should something like this be attempted…
Click to expand...

That's a good question. I don't know it the limitation is in the hydraulic parts or in the roller itself.
I have heard somewhere that hydraulic roller camshafts have other style ramps, demanding very small lash settings if used with solid lifters.
 
As stated, the open pressure is a little high but it's pretty safe to say it's closer to 130 pounds of seat than 140 pounds after the springs break in. I am also curious how much spring pressure the axle and rollers are capable of handling, because converting them to solid isn't too complicated to do.
 
Swede408 said:
Well probably that's the subtle sound remaining after startup.
Would a "slow leakdown" lifter like HGH 5006S Hughes Engines be an upgrade, or are all stock style Magnum lifters limited to around 130/330 lbs?

I notice that Hughes recommends both the stock type HGH5006 and the fast bleed HUG 5007 for springs up to 145/358 lbs (for instance for cam SER7076ALN8).
Wouldn't the fast bleed lifter cause more bottoming out problems? Or perhaps the limitation of the stock lifters are not only in the noise-causing bottoming out?
Click to expand...
It's more a case of iron core than the lifter.
It won't last. That's why they make them out of billet for hp applications .
I would try and keep the seat pressure around 125-135lbs and the open doesn't need much more than 315-330 for 6000ish rpm or less. Weight of valve train matters. Once it's not enough open pressure... the lifter is allowed to grow/pump up...once solid and still short on load... it starts bouncing and everything goes down hill.
 
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Swede408 said:
I do have a bit of noise even after start up, but not nearly as loud as on startup with some of the lifters drained.
I don't really get what causes this. Is it the check valve in the lifter that can't cope with the pressure, causing the lifter to bottom out?
Click to expand...
The cause is poor quality control by the lifter manufacture.
I had this same issue on my 340 with a set of hyd rollers from Comp Cams, I tried every preload you could think of nothing changed, Comp replaced them under warranty with a set of solid rollers. I sold those and replaced the hyd rollers with a set of Morel solid rollers and kept the same springs. Time will tell but I have around 250 miles on the new solid rollers and no issues.
Just search "isues with hydraulic roller lifters" and watch your computer light up.
 
Last edited:
Swede408 said:
That's a good question. I don't know it the limitation is in the hydraulic parts or in the roller itself.
I have heard somewhere that hydraulic roller camshafts have other style ramps, demanding very small lash settings if used with solid lifters.
Click to expand...

Some new info

I was just on the phone with a tech guy at Hughes, doing the best I could with my limited English lingual skills.
They said 138/369 lbs is fine for their cams. They would recommend a spring with 145/358 lbs if the springs in the head weren't already there. The choice between their lifters 5006, 5006S or 5007 are more about getting it quieter or getting "variable duration". All of them should cope with the pressures.

From this point of view I have to judge if my cam and lifters are as good as Hughes... I do believe they are cast core cams as well
 
I had the same setup in my 360.
Hydraulic roller about 540 lift,stock lifters, Trick Flow heads for up to 650 lift,roller rockers,1/2 turn preload.
I had no noise.
 
Swede408 said:
Some new info

I was just on the phone with a tech guy at Hughes, doing the best I could with my limited English lingual skills.
They said 138/369 lbs is fine for their cams. They would recommend a spring with 145/358 lbs if the springs in the head weren't already there. The choice between their lifters 5006, 5006S or 5007 are more about getting it quieter or getting "variable duration". All of them should cope with the pressures.

From this point of view I have to judge if my cam and lifters are as good as Hughes... I do believe they are cast core cams as well
Click to expand...
I run 135 lbs on my stock magnum 360.
It's been said numerous times that 140 is max recommended for an iron core roller. I have no personal experience trashing one by using more than the 135 seat load I use.
Based on the stock 90 lb seat load... you could run the seat load anywhere from there-140lbs.. as long as the rate is there and load...for instance touching 250-260lbs @.400
[email protected] , [email protected] minimum. That's jma.
 
MOPAROFFICIAL said:
I run 135 lbs on my stock magnum 360.
It's been said numerous times that 140 is max recommended for an iron core roller. I have no personal experience trashing one by using more than the 135 seat load I use.
Based on the stock 90 lb seat load... you could run the seat load anywhere from there-140lbs.. as long as the rate is there and load...for instance touching 250-260lbs @.400
[email protected] , [email protected] minimum. That's jma.
Click to expand...

Sounds good,
I also just got info from Lunati. They say 138/369 is just fine, and that the cam can handle up to 500 lbs. He didn't think there would be any problems with the stock lifters either.

Well, I guess I'll stop worrying and keep running! At least as long as no new noises appear.
 
Swede408 said:
Sounds good,
I also just got info from Lunati. They say 138/369 is just fine, and that the cam can handle up to 500 lbs. He didn't think there would be any problems with the stock lifters either.

Well, I guess I'll stop worrying and keep running! At least as long as no new noises appear.
Click to expand...
They said their cast iron roller cam can take 500 open pressure? As long as they knew you weren't talking about a billet core, sweet.
Just an echo.. as far as I know ..it's the constant extreme seat load that can hurt a cast iron roller cam and not really so much the open of your average load requirement. Rock on!
 
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