A little PTV problem. Pulled motor with pics.
Thread Starter
Joined: May 2006
Posts: 4,218
Likes: 3
From: Birmingham AL.
A little PTV problem. Pulled motor with pics. THIS WAS NOT BC OF THE MS4 CAM!!!Ok guys this all happened not to long ago. I was driving to work one morning, started heading up this mountain and my car started to knock. So i drove the mile to work and parked her where she died. Well we finally got the motor out this past weekend 
.. Here is the damage. Oh and i have the MS4 cam on all stock bottom end and heads.
Here is the beginning:
#1 Cylinder problem:
#6 Cylinder problem
Well i think I found the problem!!
.. Here is the damage. Oh and i have the MS4 cam on all stock bottom end and heads.Here is the beginning:
#1 Cylinder problem:
#6 Cylinder problem
Well i think I found the problem!!
Last edited by bjamick; Dec 11, 2007 at 10:43 PM.
The PTV clearance was prob REALLY close and was fine until a valve floated for a split sec, Id say magnaflux and fly cut and hopefully none of the valves bent or chipped.
Thread Starter
Joined: May 2006
Posts: 4,218
Likes: 3
From: Birmingham AL.
Believe it or not guys im actually 19 Y/O and have done every mod on the car myself w? A few helping hands ..
What caused this problem is not from over revving bc the car still had the stock rev limiter (6200rpm). I believe bc i never got it fully tuned just good enough to run and idle in traffic. I think i had it running so rich that the fuel washed down the cylinder walls and steadily kept sending oil out the exhaust and all that good stuff. So finally i think the oil got low enough that when i started going up the mountain. All the oil was at the back of the oil pan leaving #1 to #6 W/O oil. This caused the motor to spin the rod bearing and i think caused it to make the piston actually go a lil higher then usual on those 2 particular cylinders. Thats how the piston got stamped i believe.
The cam and all that stuff had prob 800 miles on it so i've never had a problem out of it. ALways pulled like a raped ape but i think my stupidity of not getting it tuned got the best of me
.
..What caused this problem is not from over revving bc the car still had the stock rev limiter (6200rpm). I believe bc i never got it fully tuned just good enough to run and idle in traffic. I think i had it running so rich that the fuel washed down the cylinder walls and steadily kept sending oil out the exhaust and all that good stuff. So finally i think the oil got low enough that when i started going up the mountain. All the oil was at the back of the oil pan leaving #1 to #6 W/O oil. This caused the motor to spin the rod bearing and i think caused it to make the piston actually go a lil higher then usual on those 2 particular cylinders. Thats how the piston got stamped i believe.
The cam and all that stuff had prob 800 miles on it so i've never had a problem out of it. ALways pulled like a raped ape but i think my stupidity of not getting it tuned got the best of me
. Yup, looks like you spun a bearing or two and had the piston come out of the hole quite a bit. If you didn't have many miles since your install, it's possible the bearing failed due to debris that got in at that time. The pistons don't look that bad, but I'd get the heads checked out for sure. It's a good excuse to get some upgrades while you're at it
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TECH Senior Member
Joined: Mar 2004
Posts: 14,620
Likes: 17
From: BFE
That means that the cam clearances were too tight to begin with. I will repeat this a million times (not that anyone listens).
Any cam with less than .080 intake and .100 exhaust clearance (unless a racing application) should flycut.
That range above should be Super minimum on a hydraulic Street setup
All else is a crap shoot.
This is not the first time i see this with the MS4 or some other big cams (T-Rex, Vengeance etc...or custom in those duration range and VEs)
The other thing is that cams that big should always be doctored and degreed to verify grind and specs.
Any cam with less than .080 intake and .100 exhaust clearance (unless a racing application) should flycut.
That range above should be Super minimum on a hydraulic Street setup
All else is a crap shoot.
This is not the first time i see this with the MS4 or some other big cams (T-Rex, Vengeance etc...or custom in those duration range and VEs)
The other thing is that cams that big should always be doctored and degreed to verify grind and specs.
That means that the cam clearances were too tight to begin with. I will repeat this a million times (not that anyone listens).
Any cam with less than .080 intake and .100 exhaust clearance (unless a racing application) should flycut.
That range above should be Super minimum on a hydraulic Street setup
All else is a crap shoot.
This is not the first time i see this with the MS4 or some other big cams (T-Rex, Vengeance etc...or custom in those duration range and VEs)
Any cam with less than .080 intake and .100 exhaust clearance (unless a racing application) should flycut.
That range above should be Super minimum on a hydraulic Street setup
All else is a crap shoot.
This is not the first time i see this with the MS4 or some other big cams (T-Rex, Vengeance etc...or custom in those duration range and VEs)
Thread Starter
Joined: May 2006
Posts: 4,218
Likes: 3
From: Birmingham AL.
Yep Pred.Z is right. But it still would have spun the bearing whether i did it or not .. But hell the car had 110k on it and was beat on on a reg. basis so i think its ok. Now i've got a set of P&P 5.3 heads to go on it LS6 intake and im buying new rods and pistons and bearings. So when she comes back out im taking her straight up to SPeedsouth to get a tune 
.. The pistons will have valve reliefs so i will never have to worry about PTV problems ever again 
.
I hope you newbs learned something from this. Smartest thing to do i never hold off on a tune, it will come back and bite you in the ***.
.. But hell the car had 110k on it and was beat on on a reg. basis so i think its ok. Now i've got a set of P&P 5.3 heads to go on it LS6 intake and im buying new rods and pistons and bearings. So when she comes back out im taking her straight up to SPeedsouth to get a tune .. The pistons will have valve reliefs so i will never have to worry about PTV problems ever again .I hope you newbs learned something from this. Smartest thing to do i never hold off on a tune, it will come back and bite you in the ***.
Hi PREDATOR-Z,
Those rules are the bases you would like to hear from every camshaft provider...compliment to you for insisting and trying to help.
Christian
Now that's a good theory, but if it's true why are we looking at pictures of the engine removal and piston crowns instead of big end rod shells to prove you are right. If you can do all this engine work yourself why aren't you smart enough to have sufficient oil in the pan? Don't blame it on the mountain.
Maybe as long as he was driving on level ground the oil level was sufficient, but as soon as he started up that damn mountain the pickup went into cavitation. Either way it wasn't the mountains fault.
Thread Starter
Joined: May 2006
Posts: 4,218
Likes: 3
From: Birmingham AL.
I don't know where everyone is coming up with a PTV issue on this motor. Look at the pics and you can clearly see where the pistons hit the cylinder heads! To me it looks like the motor spun a couple of rod bearings which resulted in the PTV issue when the pistons came out of the hole. That has nothing to do with the camshafts size. You can do the same thing with a 224 duration camshaft with a ton of PTV. Anyone familiar with engines would see that well before the PTV issue. Those would be the only cylinders with both PTV contact and piston to head contact. That instantly tells you that a bearing had an issue.
I don't know where everyone is coming up with a PTV issue on this motor. Look at the pics and you can clearly see where the pistons hit the cylinder heads! To me it looks like the motor spun a couple of rod bearings which resulted in the PTV issue when the pistons came out of the hole. That has nothing to do with the camshafts size. You can do the same thing with a 224 duration camshaft with a ton of PTV. Anyone familiar with engines would see that well before the PTV issue. Those would be the only cylinders with both PTV contact and piston to head contact. That instantly tells you that a bearing had an issue.
good luck with the rebuild bro