Dumb lifter questions.......

I'm not really experienced with SBF, just have to share that right off. I've replaced inlet manifolds/carbs, done tune ups, etc. but have never had the heads off of a SBF or messed with rockers or valves.

Now that I have the engine/transaxle out of my bastard "Fortus" ('88 Esprit with SBF power), and have most of the parts for the drivetrain (transaxle, carb, headers, shifter, etc.) I now need to source the appropriate SBF engine.

So here's the question: can someone help me understand the basics of hydraulic lifter v. solid, pros/cons, etc? I'm accustomed to adjusting valves using rockers with a feeler gauge (ie. MG/triumph/porsche) or cams (Alfa/ferrari) using shims....but I don't really have a clue with SBF lifters and valves. Help?

Thanks
 
Thank you Dave, appreciate the link and info. That's helpful.

I'm really hoping that someone might just give me a very basic description of what's the difference between solid lifters and hydraulic....? I'm guessing that solid is just a fixed length rod which is adjusted with a nut and set screw somehow to adjust the valves....whereas the hydraulic somehow automatically sets the clearance. But, again, I really don't know.

Are there pros/cons to each/either? What are they?

Any information helps. Thank you.
 
Typically you will be able to ger higher revs with solid lifters, to adjust them you use a feeler gauge. Hydraulic lifters you adjust to zero lash and then pre load them about 1/4 to 1/2turn.
 

Randy V

Admin
Lifetime Supporter
For road going cars, there is no need for solid lifters any longer. If you are building something new and for the street, I would source a late-model Ford 302 HO engine from a Mustang. It will have a hydraulic roller cam in it and will run literally forever on the oils mandated to us by the EPA today (no Zinc / ZDDP)...

Solid lifters are typically lighter than are hydraulics. It is the lighter weight that helps them rev higher than hydraulics. Hydraulics are not lashed with any clearance and rely on oil pressure inside the lifter itself to take up any variation in slack. They are also substantially quieter than solids for this very reason.
 

PeteB

GT40s Supporter
Other than hydraulic versus solid, you'll also need to determine if you want roller or flat tappet lifters. Roller lifters allow for steeper ramp up on the cam lobes and don't require the cam break-in that flat tappet lifters require. Roller lifters do require either a block originally made for roller lifters or a retrofit kit and small base circle cam or link-bar lifters.
 

Tim Terry

Supporter
Cliff,
Having just completed a new engine for my old Mustang, I should weigh in. I had solid lifters for the previous Mustang engine and have solid lifters for the Shelby FE stroker 452 engine in my Cobra replica.

If you can afford a little more for the hydraulic roller setup, please go that way. You will adjust them exactly one time and probably never worry about them again. And the performance is just as good or better over the entire rpm range of the engine.

My Two Cents
 
Thank you Dave, appreciate the link and info. That's helpful.

I'm really hoping that someone might just give me a very basic description of what's the difference between solid lifters and hydraulic....? I'm guessing that solid is just a fixed length rod which is adjusted with a nut and set screw somehow to adjust the valves....whereas the hydraulic somehow automatically sets the clearance. But, again, I really don't know.

Are there pros/cons to each/either? What are they?

Any information helps. Thank you.
You are pretty much right in your description. Solid lifter, you adjust the nut on the rocker arm, hydraulic lifters pump up with oil and take up the lash automatically.

The pros and cons:
Hydraulic is what street engines use because they are maintenance free. You adjust them once when you install your valve springs and rocker arms and thats it. They make these in both roller and non-roller configurations.
Pros: Maintenance free and reliable.
Cons: heavy and 'pump up' too much when RPM's get high. Heavy limits the rpm and the 'pump up' issue holds the valves open all the time. You can build a pretty high RPM engine with them though, just have to know what you're doing.

Sold is a different story. They also make these in roller and non-roller. A solid-roller is the highest performance lifter that is made and is intended for high RPM race engines. The cons are they are short lived and are never to be driven on the street. Of course you can drive them on the street, but its always a risk. The problem with a solid roller is that they always have a little bit of lash. This lash means that the lifters are free to bounce within the confines of its lash, but when they do this, the little bearings in the rollers really take a pounding and eventually get a flat spot and fail. When they fail, all of the little needle bearings come out and go directly into your oil supply and wreak havoc on your engine, which is then effectively destroyed.

I'm not clear on why, but they say solid rollers take more of a beating at idle than they do at high rpm. Thats why they are not good on the street.

Of course, there are those masochists who have to have the most insane engine on the street and do run solid rollers. But they check the lash often, and keep a log of which lifters need the most adjustment. If they find that one lifter is requiring more adjustment than the others, they replace that lifter because thats the warning sign its going to go. Or of they hear even the slightest sound that something might be wrong, they quickly shut down the engine and check the lifters.

They say the lifespan of a solid roller on the street is anywhere from a few thousand to 20k miles. You never know when one is going to let go and why close tabs must be kept.
 
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