Everyone that can,come down to Petersburg Va for fun Ford wknd. at VMP.We only get one day this yr,Sat,it`s going to be in the 70s sunny & beautiful,18th June.It was 100 degrees last yr & turn out was low,so if we want them to keep having this event we need a large turn out.They always hold Super Chevy in May when it is cool & they have a huge turn out,so tell your Ford friends to COME ON DOWN for a good time so we can keep this event alive.
Greg, let's revisit this lifter pre-load issue. I pulled the intake today to install the short stroke hydraulic roller lifters. Turns out they will not go in without pulling the heads. The stock ones will, but not the Comp short throw. I'm not going to pull the heads. I'll leave that for after the season. But, I noticed that when the cam is on the base circle (#1 cylinder at TDC on compression stroke) with both valves closed the rockers are loose and the push rods spin easily. The last time the engine was started was yesterday when I pulled it into the bay. Are they loose because the lifters have collapsed overnight, or because there is insufficient pre-load? My understanding of hydraulic lifter operation is that the spring in the lifter will keep the pushrods tight even when the oil has drained out of them. That is, the pre-load is adjusted against the spring when the engine oil pressure is zero. I know that I can adjust them with the engine running and that that is a more accurate method (albeit more messy), but can/should I adjust the 1/4 turn of pre-load cold or adjust them to zero lash cold then set the pre-load with it running? If they were only at zero lash as they appear to be to me, then could that be the source of my limited rpm at 6200?
It sounds to me like the lifters are trashed. Even if the check ball is allowing excessive bleed off overnight the spring should most definetely be resisting collapse. Should easily hold the preload when set wet or dry. I would suggest disassembling one or two lifters to do an internal inspection. Very simple design and easy to reassemble.
That's a good point. I just checked the lifters on the #1 and they are still pumped up. But, there is no pre-load on any of them. Some of them I can get a .002 feeler gauge between the rocker tip and the valve end. It's looks to me that the pre-load was never set. The question is: should I put a 1/4 turn on them cold or do it with it running? BTW, the stock lifters were new when installed. I did not build the engine, I had it built.
I'm confused. I thought you said you preset all these lifters when the rockers were upgraded.. and they lost preload and loosened back up on the drivers side?
No, I haven't done anything to it. This is the first time the valve covers have been off. I pulled the intake today to upgrade the lifters to Comp short-throw, but they won't go in unless I pull the head. I just noticed that the rockers seemed loose.
We'll hell.. I must be losing my mind even faster than I thought I was. Would have sworn you asked something about potential oiling pressure issues affecting your preload on this engine. I must be merging your rpm limitation concerns with whoever recently posted about 5.0 oiling system. Sorry.. my bad.. need to get off this phone and reread to get back on track here.
ok.. I looked again and that's exactly what I did here. Merged two entirely different subjects from two different posters together in me old timey brain. http://mmb.maverick.to/threads/5-0-oiling-system.107981/ So you're is likely easier to rectify. I believe I may have said all this before when you were talking about concerns with the potential high rpm limitations of these stock lifters but I will reiterate in case I remembered that wrong too. lol Readjust ALL the valves based on the "EO/IC method" and set them to about 1/4 turn plunger preload. This will assure that you have established consistency between all valves. If they are a bit noisy with the lighter preload then you could add an additional 1/8 - 1/4 turn to each and every one to quiet them down a bit more but keep in mind that the more preload you use the more potential for the valves to stand open that same amount.. or more.. if the engine overrevs beyond the springs ability to maintain control. Get too carried away and you can even kiss pistons with a bigger duration/lift cam. OEM lifters have a harder time metering at higher rpm so the chances are very real to stand a valve open and lighter preloads allow them to have greater margin against any major issues. I typically use no more than about 1/8 turn on all hydro rollers.. OEM or otherwise. Increases noise levels slightly.. but they run better up into the higher rev range. You might even find that they get back the rpm you're after here without doing the lifter swap altogether. Also be sure to relieve all the rockers so you can verify that you have no collapsed lifters. Using a pushrod it's easy to check that the plungers spring is still doing it's job of keeping the preload where it was originally set. Also a good time to check all the lifter rollers and also use a mirror to look at the cam lobes to catch any soft lobe wear issues.
Sounds like an awesome setup. I don't think anyone calculated the theoretical rear wheel horsepower. The program I used said 287. Keep in mind that's rear wheel HP, not dyno HP. MD
Ran an all time best of 12.323 today. Won the first round, lost by .0014 in the second. I think the car spun the slicks about one revolution in the second round which was enough for me to miss my dial-in by .059.
Do you have screw in studs? If not you might want to look to see if the studs are being pulled out. They are pressed in and if they are not pinned or screw in they tend to pull out with larger lift cams. Just a thought.
