[BlueinTN]

Originally Posted by KingLT1

The cam has nothing to do with lifter preload. There is no lash on a hydraulic cam valvetrain. That is solid roller stuff...On hydraulic cams, you set the lifter preload based on the specs of the lifter you have chosen. Ideally you want to be in the middle of the lifters plunger travel.

Two pages before you talked about setting the preload for different scenarios? Lifters/rpms etc I mis read what you said. if the lifters pump up you may want to set them tighter get some more RPM?


I understand were trying to "reinvent the wheel" so to speak on cam in block setups. Im new. Im here to learn.

[oldman]

Originally Posted by BlueinTN

Two pages before you talked about setting the preload for different scenarios? Lifters/rpms etc I mis read what you said. if the lifters pump up you may want to set them tighter get some more RPM?


I understand were trying to "reinvent the wheel" so to speak on cam in block setups. Im new. Im here to learn.

You should be looking at either the short throw Johnson with the "R: or maybe the new comp cam
https://www.tickperformance.com/comp...1-lsx-engines/

You may also look at this:
https://gwatneyperformance.com/lifte...ont-hurt-will/


for me I'm luck to be able to get (with the selection of various length push rods) to get the plungers to the middle of travel. At some point one needs to go to fully adjustable true rollers to get everything setup correctly and easily.

[KingLT1]

Originally Posted by BlueinTN

Two pages before you talked about setting the preload for different scenarios? Lifters/rpms etc I mis read what you said. if the lifters pump up you may want to set them tighter get some more RPM?


I understand were trying to "reinvent the wheel" so to speak on cam in block setups. Im new. Im here to learn.

Imo you can't really keep a hydraulic lifter with .200 travel from pumping up by increasing preload. once you go past 1/2 travel you increase the risk of bottoming out. Ideally you want to run a short or reduced travel lifter for something in a high rpm application.

I am glad you are here to learn...I am always looking to learn something new as well. It's the only way you progress. Oldman has been very helpful on this forum. Welcome aboard!!

[L78toLT1]

I'm certainly still learning after 45 years of hot rodding motorcycles, boats, cars, etc. Hell, even my chainsaw is hotrodded.
This is a good thread. I've built dozens of motors over the years, just like oldman. 90+% of my catastrophic failures have been valve train related

[Darth Martel]

Wow some great information in here.

[Tim M]

I may have missed it, but what constitutes a failed lifter? The wheel can seize/stop moving, but how else does it fail - ceases to take up the lash during operation? Causing a 'tick'?

[Darth Martel]

This is what my installer sent me when he pulled the failed lifter.

[KingLT1]

Originally Posted by Tim M

I may have missed it, but what constitutes a failed lifter? The wheel can seize/stop moving, but how else does it fail - ceases to take up the lash during operation? Causing a 'tick'?

Collapsed plunger. Yes it will tick/rattle like crazy.


Here is a good read on LS/LT push rod length and setup.

http://www.superchevy.com/how-to/eng...d-performance/

[oldman]

by color they look like: https://www.texas-speed.com/p-594-co...r-lifters.aspx


Johnson have black plunger

So they are not el cheapo. I wounder what the oil pressure was / is? the pump is finicky on reinstall. To be honest with you ( I have taken my OEM pump apart) I don't really understand how this variable pressure pump works compared to the LS pump. Well "works" is not the correct word, I under stand how it works, I don't understand how it centers itself when new. I have centered LS pumps. Anyway there is a loss ring of some sort that gets distorted during initial install and that is why the pump has to be "marked" to the block.

[oldman]

Originally Posted by Tim M

I may have missed it, but what constitutes a failed lifter? The wheel can seize/stop moving, but how else does it fail - ceases to take up the lash during operation? Causing a 'tick'?

My lifter failed when it flat-spotted the wheel. Other portions of the cam show wear on the deceleration ramp indicating valve float. I was on the stock bottom end so I was not really into reving the motor back end. From memory I was shift at 6600, fuel cut at 6800 rpm. I have always been paranoid about LS / LT1 rod bolt failure from 1997. The wear pattern on the cam could indicate my setup could have been losing control of the valvetrain after the nose of the cam. It was a TSP cam and the commonly used TSP twin valve springs. So ahem it "should have worked". But who knows? It could be the failure of the "LS7" lifters with substandard wheels. I think I need to say that instead of just pointing the finger at TSP. The other lifter failures I know about are also on the wheel end. But I'm not a vendor so I see a much more limited amounts of failure, but I would say that I see higher mileage failure in general. Basically street driven cars.

What I do know is most vendors including TSP use a pretty aggressive ramp profile. While GM and Cam Motion use a tame profile, yes this leaves power on the table.

back to the OP, two lifter failures in a row, even with std pushrods makes no sense. I'd take the lifter apart and check for contaminants and question if there is enough oil pressure in the galley. I'd cut the oil filter into parts looking for contaminants too.

Oh maybe I missed it what version of the TxSpeed cam and what limit / lock was the phaser, was this an intake valve or exhaust valve lifter, was the last one an intake or exhaust valve lifter. My thinking could it be piston to valve contract?? I mean two failures, heck I'm wondering if all the new push rods are all +.025 long (7.875) and maybe the head was shaved .010 or something like that?


"DESCRIPTION:
Pro Magnum Hydraulic Roller Lifters
Chevrolet Small block. For use in blocks originally equipped with hydraulic roller cam. 1987 to present, and GEN III, LS1, LS2, and LS6.

COMP Cams® Pro Magnum Hydraulic Roller Lifters™ are specifically designed to perform at higher engine speeds. When engines are equipped with a hydraulic camshaft, high rpm is limited by the improper position of the internal piston as the lifter inevitably "pumps up". This improper location results in open valves and therefore leads to lost power or sometimes even engine failure. NOTE: These lifters require an adjustable valve train (check here for adjustable valve train components), and must be pre-loaded to .002" to .004" for proper operation!"

[oldman]

I thought this was interesting:
I emailed comp a link to this post and here was the reply i got.

"Any of our "R" series lifters are race lifters. The preload must be
maintained, when the lifter pumps up with oil it acts like a solid.
The people on these message boards complain about only getting 1000 or 3000 miles, turning the motor 6500 + and finding clips in the oil pan and
probably never checked the preload in those 1000 or 3000 miles. How
many pass's down a quarter mile does that equal to?? (750 passes) Most
racers with solid rollers replace or have there lifters rebuilt around 50-100
pass's depending on the application. Let me remind you this is a race
lifter. They are very picky on the .002-.004 of preload if that is not
there the clips comes out. Using a dial indicter when setting this
small amount of preload is the most accurate way. This needs to check
depending on how hard the engine is ran and how often. We will replace the
lifters with new lifters but only after the customer is told this very same
thing. Someone hit it on the head about using an OEM style of lifters
and these should use if the person does not want check or readjust preload
on a regular time frame. If they need a set replaced have them call our
tech line (800-999-0853) and get a return # (RMA). This is limited for a
term of 1 year from the date of purchase. Feel free to post on the board
and have them call our tech dept. when needing help or have questions."

[oldman]

The superchevy article says preload is 1/2 to 1 turn. But from memory .004 to .006 is a 1/4 turn right? 32 to 34 to an inch pitch bolts. I don't know?!? Heck mine was setup a year ago and before that the "LS7" lifter has so much travel just about anything will work it is after-all stock spec production. From memory I got 16 std pushrods 2 over / undersize .025, 1 over / undersized for .050, so 22 total pushrods (plus one adjustable length one). I'mm talking .025 and Comp Cam on the Rs is talking .004 to .006, that to my mind is only possible with a full stud based roller rocker. I must be missing something here as the superchevy article is talking .1 delta on their pushrod which is TWICE as big as my biggest oversize / undersize pushrod, FOUR times as big delta on my "normal" undersize /oversize pushrods. What???

[BlackbeastSS2]

Originally Posted by oldman

I thought this was interesting:
I emailed comp a link to this post and here was the reply i got.

"Any of our "R" series lifters are race lifters. The preload must be
maintained, when the lifter pumps up with oil it acts like a solid.
The people on these message boards complain about only getting 1000 or 3000 miles, turning the motor 6500 + and finding clips in the oil pan and
probably never checked the preload in those 1000 or 3000 miles. How
many pass's down a quarter mile does that equal to?? (750 passes) Most
racers with solid rollers replace or have there lifters rebuilt around 50-100
pass's depending on the application. Let me remind you this is a race
lifter. They are very picky on the .002-.004 of preload if that is not
there the clips comes out. Using a dial indicter when setting this
small amount of preload is the most accurate way. This needs to check
depending on how hard the engine is ran and how often. We will replace the
lifters with new lifters but only after the customer is told this very same
thing. Someone hit it on the head about using an OEM style of lifters
and these should use if the person does not want check or readjust preload
on a regular time frame. If they need a set replaced have them call our
tech line (800-999-0853) and get a return # (RMA). This is limited for a
term of 1 year from the date of purchase. Feel free to post on the board
and have them call our tech dept. when needing help or have questions."

That’s very good response and bang on. Explains it very well. R is for race. Made for passes. Seems the preload is very picky. OEM for me because I don’t want to check it always. Good read because it inform me a lot with one simple reply.

[oldman]

the new and expensive comp cam ones are here:
https://www.compcams.com/short-trave...and-lt-ls.html