So I'm curious if anyone else has run into this:

Been having some issues with seems like everything, low compression, high emissions (won't pass, high HC's), rough idle, etc. The compression tests show like 95-100 hot, even after a re-ring. It's been pretty low for years, but the car has run decent and got ~25 mpg, so not complaining too much. Sig has engine details, btw. Thing is, have a spare head rebuilt with SS exhaust valves, knife-edged port partitions, but going to use stock cams again. I was tearing my old head down to pull it, with the motor at TDC. Thing is, as I unbolted the cam bearing/hold-down pieces, I noticed my intake valves close slightly as the cam raised up. I did this several times verifying nothing was lodged or off-kilter, but same thing every time. I'm using the PT lash adjusters, but stock cam followers. It there an issue mix-n'-matching these? Do I have some bad adjusters, locked in the highest spot? I know you really shouldn't be able to compress them by hand, but I assumed with no oil pressure that the valve spring leverage should be able to compress them. I'm pretty pissed/frustrated, if all this trouble and it's something this minor!! Just wondering again if anyone has had this problem.

Also, for the record, the Ferrea SS valves sit a tad shorter in the head. Machine shop recorded assembled heights, and they were about 0.020-0.025" shorter. They could've ground the seat down, but then that's putting the valve in a 'hole', losing some effective lift. I may get lucky, and the PT's might work great on the exhaust side - leave stockers for intake! lol

this probably won't help much, but in the past, i've been able to compress lifters that have been used by hand. I reinstalled them w/ no lifter tick or issues.

update:

Okay, so I'm not on crack... or at least the bad kind! I measured both lifter styles, original 2.0 is 1.879" and the PT is 1.882". Not too bad, that can be taken up with the internal spring. BUT, seated in the original 2.0 cam follower, the total height (base of HLA to top side of rocker) is 2.000" for the original and the 2.025" for the PT combo. Again, i'd think this should be taken up, but all my lifters seem to lock fully extended or something. The PT HLA (I suppose to give extra strength) is wider at the tip compared to the stock one, so it doesn't seat in as far into the follower. I suppose for the time being I'll swap back in my stock HLA's until I have some time to raid the junkyard for a 2.7 engine...

doing better, did a head swap and changed my lifters back to stock, and compression is ~140 cold. Better than 95! Idles very well now, also

Originally posted by justins71
doing better, did a head swap and changed my lifters back to stock, and compression is ~140 cold. Better than 95! Idles very well now, also

Interesting. I've run PT HLA's and stock followers for some time now, i wonder if I'm experiencing the same issue...

You sure your new compression numbers are due to the new lifters or because you pulled the head and put it back on with a new headgasket. Maybe the previous one wasnt torqued down correctly or the headgasket was damaged slightly..

Sounds kinda strange that changing the lifters could have that much of an impact on the compression.

Headgasket was 2 months old, and was in great shape when the old head was pulled. Torques were dead on, though the compression could be due to the new valves. Too many variables changed at once to point solely to HLA as the issue, but the stockers visibly didn't unseat the valve as much at the PT's. Took in for emissions, and whereas my old high/low speed HC's were like 130/700, my new numbers were 120/140! Still failed by a small margin, but that's probably due to residue in the exhaust, as well as only partially retuned for the new head. NOx were double the limit, but I think that was because I didn't highway travel to heat up the cat, or the mixture was lean, or all of the above.

Dead thread (I know) But when you switch to the PT lifters you must switch to the PT rockers as well to avoid that issue your had. The design of the the OEM rockers and the 2.7/Pt rockers are different for a reason

tactical nuke incoming - it's over