00ssmg

iTrader: (4)

I will be building an EPS cam and Texas speed PRC head build here shortly. I purchased a set of LS7 lifters for the build but i am not second guessing this purchase. I am looking for advise on what lifters i should look at running. I am trying to build a very stable and QUIET valvetrain. i plan to run a mid 230 duration cam with around .620 lift on the EPS lobes. so nothing to crazy. i also plan to upgrade to an 11/32 pushrod to eliminate higher RPM deflection. I have read a little on the Morel link bar lifters and the Brian Tooley SLR lifters. Looking for a little more direction from some experienced members or cam gurus. Looking to see what the pros and cons of each are? Thanks in advance. FYI i will be running an overkill spring on the PRC heads. the .675 max lift spring with 490lbs open pressure at .650. I know everyone will tell me to reduce spring pressure and go with a BTR .660 spring. My only concern is the springs on these heads are already purchased and Texas Speed isn't sure what other vendor springs will fit as they typically run the PRC spring on their heads. Thanks in advance.

Always2Slow

iTrader: (8)

That spring is overkill and the result of running that much pressure is you need a quality lifter that won't bleed down from it. I really like the slow leak down design lifters from johnson. If you run the link bar or non link bar style they are up to the task of running those type of pressures. Morel has a nice high end lifter for this sort of thing as well.

jake74

I run ls7 lifters,upgraded stock length comp pushrods,trunion upgrade and trick flow dual valve springs on my turbo 4.8 and spin it to 7200 with no problems. My cam is a comp with 232-236 duration 595-601 lift.

JakeFusion

iTrader: (7)

If you're running stock rockers, the .675 spring with that much open pressure is too much. Stock rockers need about 400lbs open. And EPS lobes are fine with that.

One other thing to ask: what's the weight of the valves? Is this the PRC 225 As-Cast with 2.06" valves? If so, the .675 is installed to control the weight of the valve with a roller rocker. I know they don't offer a hollow-stem upgrade, so see if they can run their .650 springs which are like 420lbs open.

The 11/32 pushrods are a good call. And I'd look at the Johnson or Morel link-bar lifters... not the $300 sets. The $575 sets.

svede1212

iTrader: (3)

I am in the process of spending a boat load of cash to rebuild an engine that "cheap" $350 lifters trashed. What I found out is all of the cheaper ones use cast metal bodies. If there is an issue the housing will crack and you will lose the roller and cam and like me might be pulling the block to get it fixed if possible. I hate spending that much on lifters but the higher end Morels/Lunatis that are NOT the cheap "street" versions use billet steel bodies that don't suffer from the limitation of a brittle body and is what I will use this time. Wish I had gone with them to start with.

Brian Tooley Racing

iTrader: (13)

What cam, lifters, pushrods (brand), rockers and springs did you have? TIA

96capricemgr

iTrader: (1)

This sounds like a fluke failure, a LOT of us have used OEM lifters in performance applications without a hitch.
The OP should be looking at a performance lifter/rocker with as much spring pressure as he is looking at but at the same time I don't think your one off very unfortunate incident means we should all spend more on lifters than we do the cam.

svede1212

iTrader: (3)

I had the SteetSweeper HT cam that I had been running for 6 years, nearly 5 of those with stock lifters. I "upgraded" to Lunati Street lifters when I had the heads off for "peace of mind". They were paired with trunnion upgraded stock rockers, a set of Lunati dual springs and Comp rods (all under 10k miles) with a preload of .025. The rev limiter was at 6,500 and that set up had only had one pass at the track. It broke within 2 seconds of starting up the car at my doctor's parking lot. That took out the timing chain from jammed roller, 9 valves, cam, cam sensor and a second pair of lifters when the roller came around and cracked one on an opposing set. You could see a large witness mark where the roller pin had come out and caught in the bore on the upstroke.

I'm in the process of rebuilding the entire engine from the disaster. I had to grind off the link bars to pound the two different jammed lifters out and what surprised me was how brittle the bodies were. The first one I tapped (and not that hard as space is tight) and the formerly intact top shattered like a china plate. When I got them out I bent with my fingers one of the bottom pieces that was splayed out and it just cracked off. Investigation found to cut costs they cast bodies of the cheaper ones and cast metal is brittle compared to the more expensive ones that use billet steel. IMHO brittle isn't a good material for a part that can get slammed. It's obvious the roller pin had come out for whatever reason.

I may have just been a freak thing. I don't think I "floated" the valves and given the very expensive cost of a failure I think I made a huge mistake "saving" money on a critical part.

Brian Tooley Racing

iTrader: (13)

Do you think it would be safe to say that the stock Delphi lifters were more durable than the Morel/Lunati street series lifters?

I believe the stock Delphi and LS7 Delphi lifters are made with steel bodies? I know the $199 SLR lifters that we used to sell were forged steel.

If those bodies were made from cast iron then that's a really poor design. I wonder if they were steel but something was wrong with the heat treat?

Lifters can act like a fuse in a over loaded circuit. If the valve train is unstable that can lead to lifter failures.

We've had zero issues with the Delphi lifters. I had one customer turn his stock lifters 7500 rpm making 1400 hp without a failure.

svede1212

iTrader: (3)

I know a lot of people have run the Street lifters without failure but my experience with the lifter and seeing how brittle they were has turned me off from ever recommending them. My stock lifters saw much more severe use as several years ago I used to drag race the car with a higher red line quite a bit and they held up fine. I'm pretty sure I still have those somewhere around in the junk and may want to try to see how brittle they are. . . I guess I could always use them again too. At the time I wanted to get away from the trays. So much for a "performance" lifter.

Here's the most interesting part though. The lifter failed last October. Frustration, winter and money kept me from digging deeper into it then after seeing the locked up cam so I didn't pull the engine until this summer. When I saw the issues I called Lunati. I was hoping to get an explanation of possibly what I did wrong even though I was meticulous with the setup and didn't drive it that hard or maybe at least offer a couple of replacements. The guy on the phone didn't seem surprised and told me he wouldn't recommend those to even spin to 6,500, silence and then the end of conversation.

00ssmg

iTrader: (4)

Jake Fusion i am not aware of the valve weights but i do know they are the stainless valves that PRC installs. I have two sets of rockers. I have factory with a trunnion upgrade as well as a set of yella terra 1.7's. I know YT need a higher spring rate and have thought about running them. My only concern is that i dont want to chance breaking once and destroying my build. The heads are the PRC as cast 225. there are so many different opinions with this topic. Texas Speed whom i purchase the heads from insists that the LS7's are the way to go and spending any other money is foolish and unnecessary. Everyone else you talk to seems to state that they are a week link in a cammed car with higher spring rates. I am thinking of going with the morel or the johnson's but dont know which company is better or have been around longer. Any help is appreciated guys! thanks

Brian Tooley Racing

iTrader: (13)

Chevrolet chose the drop in Johnson SLR lifters for their COPO Camaro, for what that's worth. They seem to be really good lifters.

Brian Tooley Racing

iTrader: (13)

http://www.briantooleyracing.com/johnson-drop-in-slow-leakdown-rate-lifters-2110.html

JakeFusion

iTrader: (7)

I talked to Tony Mamo and the guys at Johnson before I went with them. They did a lot of spintron testing and came up with a very rock solid design.

svede1212

iTrader: (3)

Hmmm, Johnson is only about 30 miles from me. I had not heard of them before.

Shuckman00

So the johnson lifters are a good lifter to go with? Steel bodies and strong?

Brian Tooley Racing

iTrader: (13)

As far as I know they're a forged steel body, which should be very strong.

Havoc40

Johnson's are forged 1018 Steel blanks, which are then CNC'd to final dimensions. Chosen over 8620 for roller pocket strength. The grain structure from forging actually increases durability and dimensional repeatability in this area. This allows for an encapsulated roller vs. the open fork design. The encapsulated rollers, when using a standard GM diameter lifter, will take higher spring loads than the open fork design. Even though it's using the smaller .700 diameter rollers....

JakeFusion

iTrader: (7)

Yup. Randy (Havoc) knows what's up...

Shuckman00

Thanks guys for the info. I do plan on doing a few things this winter and while I have it apart I might as well replace the lifters.