[rohrt]

I was all on board to go the LS lifter route, but just couldn't pull the trigger. I feel bad for Randy going to all that work to make the plate system only to give up on the idea.

To me it seemed like there was too much block casting inconsistency for the plate system to work.
Too much cam inconsistency - But Randy had a few flavors of lifters to accommodate the different lifts/base circle.
Didn't like how the dog bones would lift up and needed modified with use with the spider.
Didn't like that there just were not very many people using it.

I think the lifter weight is more significant. Heavy lifters need more spring pressure. More spring pressure = more wear on the rollers and thus more prone to fail. Not sure where lifter float come into play but I would imagine that too.

In the end I went the johnson short travel rollers too. Glad I got them at the 700 price and not the 1100 price.

[1969GPSJ]

Sorry to hear that you put all that work into trying to figure out Jim's LS lifter conversion for our Poncho's. It was still really useful info for those contemplating the project! I appreciate your experiments and the videos you do documenting them. Quite a bit on your firebird is similar to my '69 GP.
I think after looking at Jim's original information that I am still heading down the path to using the F*rd spider and dogbones to use an LS style lifter in my 428. I'm probably going to talk to both Kauffman, Butler, and DCI (Don is building my friends aluminum RAV headed engine now https://www.facebook.com/DCIMotorspo...qiMWmPriBrhqwl) before I start buying parts though.

Originally Posted by rohrt

I was all on board to go the LS lifter route, but just couldn't pull the trigger. I feel bad for Randy going to all that work to make the plate system only to give up on the idea.

To me it seemed like there was too much block casting inconsistency for the plate system to work.
Too much cam inconsistency - But Randy had a few flavors of lifters to accommodate the different lifts/base circle.
Didn't like how the dog bones would lift up and needed modified with use with the spider.
Didn't like that there just were not very many people using it.

I think the lifter weight is more significant. Heavy lifters need more spring pressure. More spring pressure = more wear on the rollers and thus more prone to fail. Not sure where lifter float come into play but I would imagine that too.

In the end I went the johnson short travel rollers too. Glad I got them at the 700 price and not the 1100 price.

[Formulajones]

Originally Posted by rohrt

I was all on board to go the LS lifter route, but just couldn't pull the trigger. I feel bad for Randy going to all that work to make the plate system only to give up on the idea.

To me it seemed like there was too much block casting inconsistency for the plate system to work.
Too much cam inconsistency - But Randy had a few flavors of lifters to accommodate the different lifts/base circle.
Didn't like how the dog bones would lift up and needed modified with use with the spider.
Didn't like that there just were not very many people using it.

I think the lifter weight is more significant. Heavy lifters need more spring pressure. More spring pressure = more wear on the rollers and thus more prone to fail. Not sure where lifter float come into play but I would imagine that too.

In the end I went the johnson short travel rollers too. Glad I got them at the 700 price and not the 1100 price.

Enough spring pressure to properly control things shouldn't be so far out of whack on a hydraulic roller setup to even worry about roller wear or failure. I think this whole thought process is really going off the deep end, and probably is more of a result of improper setup to start with than anything else.

A typical hydraulic roller in our Pontiacs, considering the valvetrain weight, really shouldn't need more than 150-160 lbs. on the seat and maybe 420-450 lbs. open as an example. Pontiacs do have heavier valvetrain with their 2.11 intake valve and 1.77 exhaust valve sizes being bigger than a SBC for example. Speaking of which a SBC might only use 130lbs as an example. But those spring pressures can easily control a hydraulic roller well beyond what most would spin their Pontiac engine to and no worry of excessive wear. In fact I set dad's Pontiac engine up with a hydraulic roller and he's running a 2.20" intake valve, it's 160 on the seats and 450 open. It's gone several thousand miles, and I think 3 years now since the change, can't even tell you how many times he's put it on the 6200 chip for one reason or another. My BBC has a 2.25 intake valve, known for valve train control problems, and runs those same spring pressures. That engine has been together almost 25 years like that with a hydraulic roller, never had a valve cover off since and has no problem spinning 6500 rpm. Going racing this Saturday with it as well as dad's car I'd bet after 25 years those spring pressures are significantly less by now. All this stuff is typical link bar setup.

I think where people get into trouble, and I've had this issue myself, is when getting into solid rollers and the spring pressures they require. Had one of those in dad's engine too, that had a very typical 240 lbs. on the seat. Tony Bischoff set that deal up and used what is an acceptable street type spring pressure for a solid roller, tight lash deal, pin oiled Crowers etc..... They lasted about 7000 miles before it ate 2 lifters. Roller wheel failure. Lobe design plays a roll in this as well but when you are using race type parts on the street, along with lash, and spring pressures up in this range, you have to expect it's not going to last forever. Crower had no other explanation, I don't hold them accountable either. It's just the nature of the beast.

Moderate hydraulic rollers however with proper spring pressure, not even on my page of concerns.