Hey, when I read about everything from an auto Honda Civic to an auto SS Camaro beating their stick alternatives, it just shows how far tranny tech has come.
I too wish there were more stick trannies available, but I might be the guy who still buys an automatic because it is-
1) Quicker, and
2) More economical, and
3) Less hassle to drive in heavy traffic.

 

Agreed
Manuals are becoming nostalgia I think.
Haha

 

I completely agree with an autotragic for heavy traffic daily use, I have yet to see an auto get better fuel economy in the real world. I'm currently looking for just such a vehicle, goals are 30mpg to offset the ROI within a year of driving 25k miles vs my suburban. I have landed on the Cruze Eco in the manual as the auto gets about 10mpg less.

But back on topic, I honestly had never thought of the other side of the lobe once it has been overcome, not really sure why, but that does make a lot of sense

 

manual transmission is an awesome theft deterrent. Especially in a cammed car. Nobody can drive it.

 

Boy, you got THAT right! LOL

 

I think you're right!

BTW.....I got some info for you....will send a PM in a few hours.

KW

 

Solid rollers are maintenance free with shims instead of adjusters. Tons of DOHC engines are shim and bucket style instead of hydraulic.

Comp has just released shimmable pushrods. When they finally release their radius tip rockers it will be the best combo on the market.

You can shim under the rocker stands too.

 

EXACTLY!!! Been trying to explain this for a couple years now. You shim this stuff into place and they stay put. amazeballs

 

Disagree.

All the OEM stuff with solid valvetrain is either OHC or low-speed diesel stuff.

Both require valve adjustments on a fairly regular basis (akin to timing belts).
Both are noisier than hydraulic. The OHC stuff gets away with this on account of the cam and valve being in such close proximity that thermal expansion and growth is WAY more stable and predictable than an OHV arrangement where cam and valves are so far apart. Thus, even a solid (OHC) valvetrain is pretty quiet. Low speed diesel stuff just ignores the increased noise - a luxury that GM does not have when it comes to selling $50k+ cars.

 

That is a really good point.
First of all you would hear the car start and you would know it's your vehicle by the sound.
Then when he tries to get away he would probably keep stalling thinking there was something wrong if he wasn't a car guy.

 

Does this apply to low lash solid rollers and solid rollers?
So you are saying you will have no maintenance free operation?
If this is true, there are some great years ahead, still.

 

Well, lash changes because things have moved...you hope because the adjuster got hammered enough to move. Aside from initial break-in, if everything is solid the only reason lash would change is due to mechanical wear.

A mild LLSR without adjusters should last 10's of thousands of miles. Taking the lash adjuster out of the rocker arm removes significant weight out of the valvetrain in a really crappy place.

There is really minimal difference between an LLSR and a solid roller. LLSR is just a tight lash solid roller. It is just a different lobe profile. The more aggressive you get the faster stuff will wear out, and the more part breakage will occur.

 

Ok. Does a low lash version make less power than a normal solid?

 

Thunderstruck has already figured this out ;https://ls1tech.com/forums/generatio...cker-arms.html

 

probably, since all the really cool kids run really aggressive solids. More seriously, the typical solids run at higher lash, say .020-0.030 cold and have VERY steep ramp rates. They are extremely fast off the seat and back on the seat. And they need to be in order to achieve the 1+ inch lifts that they do. the lobes have incredibly high area for their duration. So yes, as a whole, they likely make more power than a LLSR arrangement. LLSR on an aluminum block, I run right at zero cold lash. i ran one for a while slightly preloaded (.002-.003"). When it warms up, you gain about .010 lash due to the block expanding more than the steel pushrods. So preloaded, it ran with only .007" hot lash and was incredibly quiet. it decreased manifold vacuum vs running say a 0-.003 cold lash, because the seat to seat time increased.

As to increased maintenance, that has more to do with the springs. Think of what you're asking the springs to do. A typical "endurance" lobe type hydraulic cam has a 54 degree ramp rate (The difference between 006 and 050 duration. Shorter ramp rates are harder on springs due to not just increased acceleration but also increased jerk and snap. (acceleration is the derivative of velocity, jerk is the derivative of acceleration, snap is the derivative of jerk.) Your aggressive hydraulics have a 47 degree ramp rate. The comp LSA solid lobes (comp's version of LLSR) have a 36 degree ramp rate. Full on race solids, I cannot even begin to imagine how fast they are, but they need to be to get to 1 inch lift and back down in time. i would not be surprised if they are as low as 20. At this point, we're talking impact in addition to acceleration, jerk, or snap. You're asking the valve springs to control a tremendous amount of energy.

I bookmarked that one. it's a fantastic thread.

 

Previous post was going to get long, so I started a new post to finish the thought out.....

Cons to running LLSR can pretty much all be summed as as "setting and maintaining lash". There are several ways to accomplish this, but no matter what you do, you are going to spend more time on your valvetrain during the initial set up. Personally, I'm a valve train geometry ****. I spend easily 16-20 hours setting up a valvetrain. Way overboard, and I get it, but I find there are on the whole far more issues with the valvetrain than the rest of the engine, and especially in the LS world where the bottom ends are so stout, the valvetrain is likely to be the thing to hold you back. I digress. Sorry. Anyway, you are going to spend some time on your valvetrain. There are effectively two ways to set up lash:

1. You can get adjustable rockers. Set the wipe pattern properly (not for this post). Set the adjuster in the middle of the travel range. Measure for pushrods (also not for this post). Order a set. Install them, and then use the adjusters to find zero lash. This is the fastest and easiest method. The objection most people (myself included) have is that adjusters do not seem to stay permanently adjusted no matter what you do. So, in this case, you need to on some interval check to make sure your lash is still good. But with LLSR, this is simple. Loosen the adjuster, find dead soft touch, secure the adjuster. Fast and easy. The other objection most people have is that they are staring at this perfectly good set of stock rockers that they already own and thinking I'd sure like to save all that money I'm going to have to spend on rockers.

2. You can use the stock rockers. Cut the rocker rail into pairs, get a bunch of machine shims, Measure for pushrods without the shims, order the pushrods a bit long, shim under the pedestals until you find zero lash. Follow Thunderstrucks thread linked above. More time consuming. Also, with the stock rockers, you need to limit the amount of lift you are going to run. I would not go over .650 lift with stock rockers. you are going to scrub the valve tips. Lash caps are not a bad idea as this spreads the load and the scrubbing out so that the valve stem is better protected. I like lash caps on any stock rocker set up anyway.

3. The insanity option. You get a set of roller tip, non adjustable rockers. Set wipe pattern. Measure all 16 pushrods individually. Order them custom length .010" longer than your measurements. Order a few extras at various lengths. order machine shims. After you get all your pushrods in, remeasure all of them. Get the best match into the best valve. there are two considerations. You want the lash to be the same AND you want the shim height under the rocker pedestals to be the same so the rocker pair is not cocked. Inevitably, you end up with a bastard pair that the last two pushrods will not level the last pair of rockers. This is why you order a few extras. They will vary in length about .003 from the supplier, so the few extras should give you options to get the last rocker pair set properly. There is a lot of installing, removing, and reinstalling with this option, and a lot of measuring and remeasuring.

So, the bottom line is, that initial installation is far more involved, and you're investing hours into doing something your hydraulic lifters already do for free - maintain lash

 

Pros to running LLSR is a longer list. Really, once the lash is set and maintained, that is where the advantages to hydraulics end. There are no other reasons to run hydraulics beyond maintaining lash.

1. Faster ramp rates mean that at comparable durations, you have better intake vacuum vs hydraulics. My 248/255 solid cam in my 428 idles at 60-65 kpa MAP. My 227/235 cam in my 346 idled at 55-60 MAP. So that should give you some idea.

2. Hydraulic arrangements have a mixture of delayed reactions and overcompensations, commonly referred to as pumping losses. Your valve managed by a solid lifter is going to follow the cam lobe much more precisely than a hydraulic lifter will be able to. As the lobe lifts, there is no plunger that compresses. the valve just starts to move.

3. High RPM stability. If you have ever run a stock lifter and then a short travel lifter, you have likely noticed your higher RPM was crisper and cleaner. Solids are even better. The engine just revs so much cleaner and easier. i cannot give a scientific sounding description to this, but Its something you immediately notice. And when you rev to peak power, it just.....keeps.....pulling. You can carry well past peak and not feel like the motor is rolling over. Pardon the expression, but the motor jsut feels a lot more "solid" at higher RPM.

4. Improved throttle response. I found that the solid lifters actually removed weight from the valve train, which in turn made the engine incredibly responsive. If you've ever been guilty of measuring your car's performance by how much it scares you - and then of course that wears off, so you want more - When I jumped from hydraulic to solid, that first time hitting the car was both scary and exhilarating thing.

5. Faster ramp rates mean more lobe area, which means more power. you will make good power with a LLSR valvetrain, assuming the cam is properly spec'd. Note that the LLSR ramp rates are not near as aggressive as more traditional solid lobes, so I have not yet encountered reduced valvespring life due to LLSR

I'm sure there are other advantages I'm missing, but I think you get the idea.

 

That's a good write up Darth.
A bit of a pain to set up but once done, it's all good from there.
If i had a LLSR I would probably check Lash once or twice a year.

 

I use the insanity option. I have not had to readjust anything yet using that method. I pulled apart my first one three times and remeasured everything, and it was still perfect the way I had set it up. The one I'm on now, i haven't bothered. I finally realized, since I set lash to zero, all I need to do is wiggle the rockers at TDC. if they are loose sideways, but not up and down, great. if they wiggle up and down, something wore. So far, though, it has never happened. If they are banjo tight, I'm on the wrong TDC.

 

Comp always working on sumin new, LOL