Lifter Technology Selection

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gzig5

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Beyond the issues with the execution of the selected lifter system in an old Mopar block, how do you make the call for the more expensive, harder to execute roller hardware? I'm still learning so please have some patience. I get the difference between solid and hydraulic tappets and understand (I think) why solid work better at high rpm. So awhy would you go with a roller over a flat tappet? Reduced friction so more HP? Do hydraulic roller do better at higher rpm than hydraulic flat tappet? Seems solid roller would be the ultimate but it doesn't seem like many folks use them on street engines, or at least to the extent that solid flat tappets are used.
 
Beyond the issues with the execution of the selected lifter system in an old Mopar block, how do you make the call for the more expensive, harder to execute roller hardware? I'm still learning so please have some patience. I get the difference between solid and hydraulic tappets and understand (I think) why solid work better at high rpm. So awhy would you go with a roller over a flat tappet? Reduced friction so more HP? Do hydraulic roller do better at higher rpm than hydraulic flat tappet? Seems solid roller would be the ultimate but it doesn't seem like many folks use them on street engines, or at least to the extent that solid flat tappets are used.



A solid lifter makes more power than a hydraulic lifter. Doesn't matter what face is on the lifter.

I didn't do a roller in my personal engine because it wasn't worth the initial cost or the maintainence. If you are running stock heads, it's damn hard to get enough spring load to control a roller valve train. I also don't do hydraulic roller lifters. I use solid rollers on hydraulic lobes.

From what you are asking, you don't need to bother with a roller cam. Unless you are talking about a hydraulic roller. Like I said, I don't use them.

In the end, if you are careful, and know how to start a fresh engine and have your **** together, a flat lifter cam is hard to beat.
 
A solid lifter makes more power than a hydraulic lifter. Doesn't matter what face is on the lifter.

Is this because you always get full valve lift from the solid? I could be misinterpreting but my impression is that there can be some lost motion with a hydraulic lifter.

I'm leaning towards a solid for my 340 build and just trying to understand the consequences of each option.
 
What does "the maintenance" mean? I figured the oem went to rollers because of (among other reasons) a reduction of maintenance.
Also, what does a Solid Roller Lifter on a Hydraulic Lobe do? I have heard of doing this, but wondered why it is done.
I am interested in knowing more as I will be going down the same path in the not to distant future (hopefully).
 
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Roller vs. Flat tappet on a street perf car is almost a wash either way. If you're already getting a modern high- performance camshaft you really won't be giving up much sticking with a FT in your 340. I am using a hydraulic roller cam in my build but that's only because I have a 5.9 Magnum shortblock which came with roller lifters from the factory. There is less internal friction but that mainly just helps MPG at lower RPMs and allows you to run oil without zinc in it. Converting an older engine to run roller cam can be close to $1000 because the lifters are much more expensive and you also have to be wary of the shorter lifter bosses on the non-roller engines which can cause oil pressure issues from the taller roller lifter body uncovering its oil feed.
 
Is this because you always get full valve lift from the solid? I could be misinterpreting but my impression is that there can be some lost motion with a hydraulic lifter.

I'm leaning towards a solid for my 340 build and just trying to understand the consequences of each option.


Nope. It's because guys think they are getting OE quiet valve train with hydraulic rollers and then they ***** because they make noise.

Also, you learn very quickly that rocker arm geometry goes nuts using retro hydraulic lifters. And, if you want to make RPM and not have the valve train best itself silly it requires something totally different than the lifter manufacturers want.

In other words, they just ain't worth it. Back in the day I was big on the HR bandwagon. It looked like the best of both worlds. What it really is is just a pain in the ***. Agressive lobes and hydraulics hate each other.
 
What does "the maintenance" mean? I figured the oem went to rollers because of (among other reasons) a reduction of maintenance.
Also, what does a Solid Roller Lifter on a Hydraulic Lobe do? I have heard of doing this, but wondered why it is done.
I am interested in knowing more as I will be going down the same path in the not to distant future (hopefully).


Maintainence means really clean, quality oil. Constantly keeping track of lash and spring loads.

Yes, guys will come along and say they never touch their roller junk. Either they are lying, or a decent flat tappet would smoke what they are running.

You can run a hydraulic lobe with a solid roller and lash at .002 cold and they work. You still get all the bullshit of a roller lifter though. At least you can run some spring pressure to help the valve train not kill itself.
 
mopekid wrote
Roller vs. Flat tappet on a street perf car is almost a wash either way. True if FT is .903 optimized, not a chevy grind, not comp cams
FT is ahead of roller at shorter durations and soild has more area under the curve at longer durations
an inverse flank roller lets the roller match the FT for shorter seat timing at a given upper lobe or a larger upper lobe at the same seat timing

If you're already getting a modern high- performance camshaft you really won't be giving up much sticking with a FT in your 340.
if modern means a lobe optimized for a Chrysler - Comp has none- lots of other good grinders do and some such as Racer Brown and Engle have for years. Today also consider Howards and Bullet and Mike Jones IDk about lunati- double check every catalog grind against the grinders grind/ lobe spec list. SBC Chevy grinds are cheaper to grind but base circle is a mismatch. Base Circle on a BBC is similar to Mopar but lifter is much smaller
Did you notice that some grinders grind Mopar solids to a smaller base circle? why?
 
how do you make the call for the more expensive, harder to execute roller hardware?
Mostly depends on how hot of an engine you want to build. Figure it like this by making use of the KISS method.

HFT, Use for an every day grocery getter with high mileage to moderate race track useage.

These cams mostly come with what most would consider lame (Chevy) lobes for performance. But you can get good results with them if your not expecting the world from them.

HR Same as above but with increased intensity with the right manufacturer or lobe. But still the same idea. The roller decreases friction and helps with the ability to increase the cam lobes intensity for lifting the valve quicker.

SFT; You can get these from a high mileage cam to a full tilt *** kickin grind. The main idea of a solid lifter is a direct connection that enables more RPM’s. Greater lift and more power through out the curve.

Solid Roller; No one really makes a mild SR cam. This style was brought out for racing and hauling back broken parts of those you defeated on your brutal rampage.

Now which one fits your intended build and wallet?


So awhy would you go with a roller over a flat tappet? Reduced friction so more HP? Do hydraulic roller do better at higher rpm than hydraulic flat tappet? Seems solid roller would be the ultimate but it doesn't seem like many folks use them on street engines, or at least to the extent that solid flat tappets are used.
Answering in order asked;

Because Conan the Barbarian said it best!
Something like, Watching the defeated heads roll, the Lamenting of their women ETC...

Yes and yes
Barely if at all to just slightly on a good cam ft and spring combo.
And the note between a regular SFT and a solid roller is, yes of course, the “cost!” Is the draw back.

Look up Cranes Ductile rocker arms cost gs inexpensive (but yet quality) roller rockers.
Then the tappets and the cam itself.

These are the 3 main items that are different in cost by a large enough margin to really make a difference.
Springs, locks and retainers are all close if not the same part number.
 
Is this because you always get full valve lift from the solid? I could be misinterpreting but my impression is that there can be some lost motion with a hydraulic lifter.
Well, not exactly but a worth mention. The hydraulic lifter is a squishy thing That has more dynamic motion that you want to calculate or think about.

The LA engines various angles from start to finish on the valve train is,,, ugly. You will loose some lift no matter how excellent your set up is. The race block is different with the 48* lifters.

With a SFT, you just have calve lash to set and every once a year or less, check and maybe reset.


I'm leaning towards a solid for my 340 build and just trying to understand the consequences of each option.
Not a bad choice. With a solid, you’ll get a few more extended top end rpm’s over a HFT.
 
Beyond the issues with the execution of the selected lifter system in an old Mopar block, how do you make the call for the more expensive, harder to execute roller hardware? It usually comes down to cost in a street or street/strip build.
I get the difference between solid and hydraulic tappets and understand (I think) why solid work better at high rpm. It's more a combination of valve action at just off-the-seat lift ranges, and valvetrain stability at high rpm.
So awhy would you go with a roller over a flat tappet?
In all but all out efforts - I wouldn't. Because of cost to properly prep a block for a solid roller, and the cost of the cam. lifters, and oil pump drive (in most cases).
Reduced friction so more HP?
Friction reduction is less about power and more about NVH and smoothness in the milder combos. Flat tappets are not high friction - if they are working right, the lifter face turns as the lifter moves it, and the lifter is mostly suspended by an oil wedge in it's bore.
Do hydraulic roller do better at higher rpm than hydraulic flat tappet?
Depends on the lifter design, bore clearance, and the lobe design. But mostly the roller does not rpm as well because it's a lot heavier and more valve spring pressure to control it. Spring pressure is a problem for hydraulics of any type.
Seems solid roller would be the ultimate but it doesn't seem like many folks use them on street engines, or at least to the extent that solid flat tappets are used.
Many use them. Many are trying to cheap out on getting them in the engine and don't make the power they should. And don't check springs or rebuild lifters as they should. Or run camshafts not designed for street type driving and use.
 
Beyond the issues with the execution of the selected lifter system in an old Mopar block, how do you make the call for the more expensive, harder to execute roller hardware? It usually comes down to cost in a street or street/strip build.
I get the difference between solid and hydraulic tappets and understand (I think) why solid work better at high rpm. It's more a combination of valve action at just off-the-seat lift ranges, and valvetrain stability at high rpm.
So awhy would you go with a roller over a flat tappet?
In all but all out efforts - I wouldn't. Because of cost to properly prep a block for a solid roller, and the cost of the cam. lifters, and oil pump drive (in most cases).
Reduced friction so more HP?
Friction reduction is less about power and more about NVH and smoothness in the milder combos. Flat tappets are not high friction - if they are working right, the lifter face turns as the lifter moves it, and the lifter is mostly suspended by an oil wedge in it's bore.
Do hydraulic roller do better at higher rpm than hydraulic flat tappet?
Depends on the lifter design, bore clearance, and the lobe design. But mostly the roller does not rpm as well because it's a lot heavier and more valve spring pressure to control it. Spring pressure is a problem for hydraulics of any type.
Seems solid roller would be the ultimate but it doesn't seem like many folks use them on street engines, or at least to the extent that solid flat tappets are used.
Many use them. Many are trying to cheap out on getting them in the engine and don't make the power they should. And don't check springs or rebuild lifters as they should. Or run camshafts not designed for street type driving and use.
Al pretty good info, but come on guys, there are street solid roller cams
out there !
 
The roller decreases friction and helps with the ability to increase the cam lobes intensity for lifting the valve quicker.

I think this tidbit about the cam lobe rate on the roller is the part that was missing for me. I haven't been paying very close attention for the last 30 years and I was really only familiar with FT lifters. Didn't realize that rollers allow more aggressive cam profiles than FT. I assume with the higher ramp rates that the springs need to be different as well.

I don't' have a problem with adjusting lash periodically so will likely be going with a solid of one sort or other for the higher rev potential. My build is nowhere near fully baked yet but at the moment it will be the 70 block and forged crank that are in the car, no stroker. I want to get as much out of the motor as I can and still keep it streetable. I'm leaning towards more corner carving than straight line fun. Was strongly leaning towards W2 heads but I'm not going to start until next year so I'll get to see what the new TF heads are all about before I commit. If the TF work out, I'll put the savings from less expensive rockers toward the cam system or fuel injection. Right now I'm getting the car running by nickle and diming it, but when the motor comes out it is going to be a buy once- cry once sorta thing. I don't want to have any regrets.
 
IMO,
for the street,
I have been very happy with;
a good quality hydraulic lifter, running on a good quality hi-lift hydraulic cam,adequate springs, with a minimum lifter preload, custom-length pushrods,and adjustable rocker arms. I get to use the best attributes of all the systems, without most/all of the cons. I never worry about lifter pump-up, nor piston to valve contact, and only very occasional lash maintenance. Cheap and effective.
The only con I think, is as YR mentioned; careful cam break-in and proper oil useage. That was/is well worth it to me.
 
Al pretty good info, but come on guys, there are street solid roller cams
out there !


I said that. But for the cost, is it worth it? Nope. Like I said, it's damn hard to get springs to control a roller valve train on most heads and I won't even consider geometry issues on both sides of the rocker, especially with retro fit hydraulic rollers.

My next build (my LAST build) won't even get roller lifters and I'm using an R block with W-2 heads, so I can get the spring load I want.
 
No hydr anything for me. The amount of attention a solid requires is usually greatly over-stated. Other than that, as an example. A roller would help me because I’m forced into a situation because of the class I race. My max valve lift is limited, for a variety of reasons. so a roller would get the valve open to a useable lift quicker, but most people aren’t constrained like that. There are easier ways to obtain your performance goal.
 
Nope. It's because guys think they are getting OE quiet valve train with hydraulic rollers and then they ***** because they make noise.

Also, you learn very quickly that rocker arm geometry goes nuts using retro hydraulic lifters. And, if you want to make RPM and not have the valve train best itself silly it requires something totally different than the lifter manufacturers want.

In other words, they just ain't worth it. Back in the day I was big on the HR bandwagon. It looked like the best of both worlds. What it really is is just a pain in the ***. Agressive lobes and hydraulics hate each other.
YR your inbox is full
I am going to trash my Comp Hyd rollers and switch to solid rollers.
Would you please provide a supplier for a good solid retro fit roller.
340 LA, X ported heads, Comp roller top end with a Comp 20-811-9 cam, stock oiling system 25psi to 60psi hot. Street A body auto trans application.
Engine made 452hp corrected on a dyno.
If at all possible I would like to be able to remove lifters without removing the heads.
Thanks in advance
Sorry for the hijack
 
IMO,
for the street,
I have been very happy with;
a good quality hydraulic lifter, running on a good quality hi-lift hydraulic cam,adequate springs, with a minimum lifter preload, custom-length pushrods,and adjustable rocker arms. I get to use the best attributes of all the systems, without most/all of the cons. I never worry about lifter pump-up, nor piston to valve contact, and only very occasional lash maintenance. Cheap and effective.
The only con I think, is as YR mentioned; careful cam break-in and proper oil useage. That was/is well worth it to me.

AJ nailed it again IMO. A typical street hot rod can use a standard Hyd. cam for years of trouble free service without draw backs. I myself will at this point in time not go to large on a Hyd cam. For me, it is just not worth going big on them anymore because I can get more from a solid cam. Where the break point is for me will probably be different for you and yet different for another. I’m yielding at 240*’s. And that is bordlinish & build target dependent.

Nothing beats a HFT for no nonsense no touch, everyday performance and longevity.
Solids up the anti in power & performance with minamal attention to valve lash.

No matter what style of cam you choose, help the cam so it’s job. Make sure your intake and exhaust systems are at there maximum flow capability for the cam to take advantage of. This will create the most efficient engine possible.
 
Didn't realize that rollers allow more aggressive cam profiles than FT.
They don't
so a roller would get the valve open to a useable lift quicker,
not usually
 
Didn't realize that rollers allow more aggressive cam profiles than FT.
They don't
so a roller would get the valve open to a useable lift quicker,
not usually

So what's the point of a roller lifter then?
 
my comment depends on the duration,
and for the FT lifter diameter and base circle
for the roller --roller diameter, base circle, and flat or inverse flank roller
so "it depends"
http://rehermorrison.com/tech-talk-43-the-trouble-with-flat-tappets/
if you look at most any cam catalog a .904 profile shows better at moderate duration than the catalog HR - hard to tell on a solid roller due to the lash - without a cam doc
an inverse radius profile can match the solid FT at moderate duration and exceed at longer durations
a mushroom lifter well the mushroom lifter General Kenetics at first out performed the solid roller in the AMC motor
hardface FT cam can work better than a roller in an Early Hemi but costs more than the roller
both approaches then go to larger tunnels and base circles
it's side thrust that limits how quick a roller can come off the seat and lifter diamater that limits the FT
on the comments above I do not see a "roller getting the valve open to a usable lift sooner" on a lift limited application
now without a lift rule and modern cylinder heads that flow at higher lifts the roller would be the way to go
It's more complicated than just the cam as the valve job changes - especially if you have to stretch the duration out and then kill the low lift flow in the valve job (sinking the valves, steeper seats, etc)
Today's roller lifters can give years of trouble free miles is one point
They can live with fuel dilution
they have less friction
 
Didn't realize that rollers allow more aggressive cam profiles than FT.
They don't
so a roller would get the valve open to a useable lift quicker,
not usually

I might substitute:
"Didn't realize that rollers allow more aggressive cam profiles than FT."
They can. But not in a street profile. This is a race part, from race engines, being used for another purpose.
"so a roller would get the valve open to a useable lift quicker"
Some will. Most won't. Like Wyrm said.
 
Wyrms description is the limits pushed on the lifter style and cam lobe to be ground with the lifter used.

This has little bearing on your build.

On your build, you will only see the difference at the track or on a dyno and never feel it on the butt dyno. Your build is a melo street mill compared to what would be seen with the proper supporting parts of the stuff he is talking about.

On “hot street machines,” I do support the aggressive lobe cams. (Though they use is questionable and on the border of practical use and return.) Because I think there is a reasonable limit to how fast and aggressive a lobe would best be seen and used on the street. The call is yours. I don’t always see a neee to hit the limit.

I mearly suggest to use an aggressive lobe and as much lift as the head can handle for the “Hot street strip machine.” Not a race grind and whooping lifts.
 
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