piston to valve contact

TNstanggurl · Oct 5, 2004

We just got done installing our almost new pi heads,comp 270's and pi intake last weekend,and ever since we have been having nothing but problems.Ther has been a bad ticking noise coming from one of the heads. it gets worse whenever you get on it a little or just whenever you raise the rpm's up.We were told before we did the swap that we could get ptvc,but we thought that we would just go ahead and try it since alot of people have tried it and got away with it.We should have just got the vt stage 2's What do you guys think ?Could it be ptvc?Please help!

stangman · Oct 5, 2004

could be that or the lifters

Back2Mustangs · Oct 5, 2004

c2see21 said:
could be that or the lifters

What lifters?

stangman · Oct 5, 2004

Back2Mustangs said:
What lifters?

oops i meant roller rockers. i've heard them making some aweful noise before, on one of my buddies car

have no idea what i was thinking when i typed that

nickthegenius · Oct 5, 2004

c2see21 said:
oops i meant roller rockers. i've heard them making some aweful noise before, on one of my buddies car

have no idea what i was thinking when i typed that

Well, see the problem is.....there are lifters. C2see21, you just fell prey to the latest in a series of retarded tech answers that I have seen lately. Kind of like last week when a guy was trying to scare possible cam swappers by telling them that you had to remove the engine to do a cam swap.

Our engines do use lifters and they have followers (rockers). And the failure rate of OEM lifters with aftermarket camshafts has been greater than with OEM cams. There have been a few people on Modular Depot that have ended up with bad lifters after cam installs. Blame has been placed on various things from faster ramp rates on the aftermarket cams to the increases spring pressure of the Comp springs. The current solution is to buy new lifters or get some very expensive solid lifters that have yet to prove themselves as reliable. I can't remember the company off the top of my head, but its some small shop that I believe is based out of PA.

For the original poster, the noise could be one of many things. It could be PTV contact and that would be bad. You can do a couple of things:

1. Get a boroscope (sp?) and check each cylinder out by looking down into the plug holes with the scope.
2. Use a very small but powerful flashlight and try the same thing. If you get a good light held at the correct angle with the piston at TDC, you can look at the top of the piston. If there are silver "cresent" or "moon" shapes, you have PTV problems.

It could also be a bad lifter as c2see21 stated. If it isn't PTV clearance, check the lifters. Pull them from their bores and check the tip to make sure it still has pressure. From what I understand, a bad lifter will compress with the slightest of force or may not even extend on its own.

Another possibility is that you did not bleed the lifters. IIRC, it was Starkie or AutomaticWeapon that installed cams and did not bleed their lifters and ended up with noise. They took them out, bled them, fired up the engine to let the lifters pump back up to where they needed to be, and the noise went away. Other members at MD have had this problem and used the same method to fix the noise.

I would check for PTV contact pronto. Then, look at the lifters. BTW, how loud is the ticking? Some people have had noise that could be heard over their exhaust, etc. Is it that loud? Are you sure it isn't just our loud injectors?

Let us know what you find out!

NasaGT · Oct 6, 2004

Good post nickthegenius. You're keeping stangnet tech alive (just barely).

stangman · Oct 6, 2004

nickthegenius said:
Well, see the problem is.....there are lifters. C2see21, you just fell prey to the latest in a series of retarded tech answers that I have seen lately. Kind of like last week when a guy was trying to scare possible cam swappers by telling them that you had to remove the engine to do a cam swap.

great info nick

but i was still originally referring to the rockers oops again my buddy got in a hurry & didn't tighten his down quite good enough (the allen screw that connects the rocker to the lifter, if i remember correctly), enough to be on there but it had a little slack. so i guess it could have been a mix of the two . that made a aweful noise he's getting his engine rebuilt right now because he did a few things wrong working on it. so MAKE SURE that you get it checked out immediately. even if it means doing a partial tear down on the top end, again. better to do that than have a engine rebuilt. keep us posted

mustang70 · Oct 6, 2004

What about an exhaust leak? Those can sound like a valve ticking. And it would get louder as you get on it due to the increase in pressure.

Rocketman · Oct 6, 2004

NasaGT said:
Good post nickthegenius. You're keeping stangnet tech alive (just barely).

Thanks for the good info. Nick. You are a tech genius.

stangman · Oct 6, 2004

mustang70 said:
What about an exhaust leak? Those can sound like a valve ticking. And it would get louder as you get on it due to the increase in pressure.

well we are assuming that it IS coming from the head, because that's what she told us. BUT, with that being said, if the egr isn't hooked up right, it makes a very loud ticking noise that sounds like it's coming from the drivers side head. so if you hear it from the drivers side, check that too. i've had that happen & it does sound like it is coming from the drivers side head. a stethescope can help find the problem if it is coming from from under the valve cover.

Indiana · Oct 6, 2004

Here is a great article on how to check PTV clearance. It would take quite some time, but will tell you very accurately what your clearance is.

http://www.fordmuscle.com/fundamentals/pistontovalve/index.shtml

nickthegenius · Oct 6, 2004

mustang70 said:
What about an exhaust leak? Those can sound like a valve ticking. And it would get louder as you get on it due to the increase in pressure.

Funny you should say that. When I fired my car up after the cam install, I had this weird squeaking sound that would increase/decrease with engine speed. The two of us that installed the cams were scratching our heads on this one. It ended up being a bad header gasket. It must have not been making full contact and was acting like a makeshift whistle or something.

So that is something else you may want to check.

TNstanggurl · Oct 9, 2004

ptvc

Well,i found out why cylinder 1 and 4 were misfireing,they both have bent valves! I am just going to get new pi heads and just use pi cams.I dont want to take anymore risks with aftermarket cams again.Thanx for all of the help

stangman · Oct 9, 2004

TNstanggurl said:
Well,i found out why cylinder 1 and 4 were misfireing,they both have bent valves! I am just going to get new pi heads and just use pi cams.I dont want to take anymore risks with aftermarket cams again.Thanx for all of the help

why get new heads when the only thing wrong with them is the 2 valves? & i'd just try some VT stage II's & sell the cams you had the problems with. JMO though

TNstanggurl · Oct 9, 2004

....

I would rather do that but i am scared that i will order 2 valves and then when we get the heads off find out that more valves are bent.We did a compression test on my car last night and cylinder number one had no compression at all and cylinder number 4 had like 50.Those are the two cylinders that were misfiring.How would i know if any other valves were bent?I have to have my car to drive to work,so i dont want to take any chances.

lopey4.6 · Oct 10, 2004

As I mentioned way earlier. You cant use the comp cams 270's on a non pi block. You need to send the cams back to comp and get the cams listed for a .500 lift not the .550 lift. Then time it right the first time and you'll be ok. Also you can get your current heads ported and have really good gains with the comp cams. Good luck

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