As you may remember, I was having problems with a collapsed lifter that was making a fair amount of noise (enough noise that I haven't driven it for a couple weeks, I was afraid it was going to leave me stranded). In order to try and fix this problem once and for all, I bought new lifters (Comp Cams high energy lifters) and new valve springs (Comp Cams 26918 "Beehive" springs). Just for kicks, I took a picture right before doing the springs for the last cylinder, so you can see what the size difference is between the springs I was using (AFR "upgraded" stock springs, #8032) and the new beehive springs. Pretty amazing: The good news is that the valvetrain is almost silent now, just a hint of rocker noise, as you would expect from a roller rocker setup. This is the first time since I put on my AFR's that there hasn't been enough clatter to hear through the firewall and bouncing off things as I go by... The SOTP meter isn't sure if there has been any effect on horsepower, but it feels plenty zippy. Weather permitting I may try to hit the track next weekend to see how its running right now, and I'm definitely going to hit the dyno to see where I'm at compared to before. I'm also thinking of picking up some Oil Extreme to dyno test, just to satisfy my curiousity. Dave
Hey what kind of a noise does a collapsed lifter make? I have a ticking/clacking from under the elbow almost over cyl # 3 but I was thinking a leak somewhere because I am not getting vacumm at idle.
Hard to describe, it's a relatively low pitched metallic tapping sound. Can you hear your ticking/clacking only at idle? *Might* it be the IAC? Seems like that makes a bit of noise when trying to compensate for a lopey idle. Dave
mine does the same type of thing, has that same ticking noise from the valvetrain, but im having trouble with it burning oil. so it smokes really bad! did either of your cars smoke?
Well I can hear it best at idle, but if I am driving around 1500-200 rpms there is a ticking I can hear kind of like exhuast but I know thats not it. It sounds more clackity clackity at idle but more ticking in low rpms. I can hear it bouncing off of objects like you said. I am only pulling 3 psi of vac at idle.
No smoke from mine except a little bit after a hard WOT pull, when vacuum sucks oil through the PCV. Only noticable on the dyno, though, not enough to see on the street. Do you get smoke at WOT, or all the time? My buddy has a 95 GT Vert that smokes at WOT, and occasionally on shifts during regular driving, and he has about the same miles as you do. 5.0's normally go a lot of miles, but not always I guess. His problem is rings, according to a recent leakdown & compression test. And he goes through a quart of oil every 300 miles or so. Dave
yeah that sounds alot like mine, then im guessing that could be my problem. mine will usually smoke at WOT but when it idles back down it will smoke then clean itself out. another thing is.. i can drive it easy without stomping on it, and it wont smoke hardly at all, but as soon as i rev it up it smokes, then continues to smoke for a lil bit. also when its cold.. or when i first start it up in the morning, it wont smoke at all, i can hold it WOT and still no smoke until it warms up? it kinda strange
Dave, you gonna try and hit a track with lower elevation??...maybe some sticky tires??...i KNOW your car has more in it... Anthony
Sounds good Dave, hopefully you've got a hold on everything now and the car runs good. Do you think this should explain the "low" dyno numbers? Joe
do you know the spring pressures of the previous springs? I have valve train noise that wont go away and I have been wondering if my springs are too much. I use comp cams 987; 121@1.8 388@1.2. I wouldnt have bought them but the book I have says325@1.25 so I didnt think they were that stiff. Id hate to replace springs because I would have to take my headers off (p heads) would just some lifters do the trick maybe?
Dan, what are the recommended seat pressures of the cam? My guess would be 120. That may be increased slightly with the use of 1.7 rockers, so I think 125 would be a good number to shoot for on the seat. IMO, you are a tad too light at the seat but your open pressures are more than enough. Joe
cam card lists 115-125 closed 300-325 open. Yes I run 1.7 rockers so lift is .515 .496 up from .467 .485
Hard to get much lower than I am now (~100 feet), but sticky tires are definitely in my plans. Anything's possible. I really believe the power is there, it's just being delivered early -- my dyno shows a lot of torque on the bottom end, and it falls off early on the top end. I honestly don't care anymore about the dyno numbers, or really even track numbers for that matter -- it's my daily driver, and the the torque makes it very fun to drive. Puts a smile on my face every day, no matter what the dyno says. My old springs were 140# on seat, 350# open. Since I did the lifters at the same time as the new springs, I can't say for sure it wasn't just a faulty lifter, chances are very good that it was -- but I didn't want to keep going back into the engine replacing things one at a time . And these beehive springs are really supposed to be kick-ass. If I ever get a bottom end that'll support 7000 RPM, these springs will really shine. As it is I probably exceed the abilities of the regular springs by shifting at 6250. Why would you have to remove the headers to replace the valve springs? Dave
Dave - I'm glad to hear you nailed that problem down. I guess that rag (MM&FF) is good for something more than just bathroom reading material! ha ha ha. Anyhow, just wanted to let you know that those Magnum roller-tip rockers cannot be used with guide plates??? WTH! My travels recently took me through Ohio and I stopped at Summit and I ended up going with the FRPP stud mounted 1.72 ratio roller rockers. I hope they work out. I should start my swap in a little over a week. You want to make a run from Oregon to sunny Phoenix to help me!?
They're installed at 1.800. Spring pressure is 130 @ 1.800, 318 @ 1.200, 313 lbs/in, coil bind @ 1.085. Dave
well, like I said. GT40P heads and regular Longtubes. The spark plug points right at the headers and their isnt enough room to hook up the hose (with the adapter because of the long reach plugs.) I think Ill change to some 15w50 oil and leave it be for a while, probably just my rockers getting old. cobra 1.7s
I think that if you had any issues with noise in your valvetrain it was not related to your old valve springs. 140 on seat 350 open should have been plenty of spring to rev to 6200 easily with those springs. Was that 350 open measured at your max cam lift or at the max lift of the springs? Did you measure these numbers or were they what AFR claimed? What is the lift on your cam? I’m curious because even with the beehive springs I don’t think 130 # on seat is quite enough to spin 7000 rpm safely.
