So I have a 95 T/A mods in sig.

Started to hear an inconsistent/intermitant valvetrain noise that prompted me to start taking things apart because it was getting more consistent and didn't sound like it was drivable.

I did a compression test and she passed with flying colors.

I swapped the valvesprings for a set of Patriot Golds and put it back together. Noise still present but not as loud. Actually could get it to be gone completely by adding lube to the crankcase.

At this point I am thinking its a sticky lifter. The new fresh valvesprings quieted the noise but the problem persisted.

So I ordered a new set of LS7 Lifters.

Took it all apart today and found that 4 of 16 lifters had damage.

I am hoping this did not damage the camshaft lobes. The lifters came off of cylinders 6 and 7 in pairs, so those wwere the only cylinders that would be effected.

Should I be concerned that the cam is damaged? These lifters have 133k miles on them. 63k miles on the aggressive cam.

 

Just look at the cam, if it looks like that it's bad.

 

Considering I don't think my head is gonna fit between the motor and cowl, I don't know how I'm gonna do that. Plus I have to have someone turn the engine over at the same time.

 

You already have the lifters out. Pull the cam out and look.

 

No need to even look at the cam to know it's toast. With that kind of damage, I would inspect some rod bearings and main bearings as well for damage.

 

100% chance the cam is roasted. If the lifters are chipped like that so is the lobe of the cam.

If you want to take a look, rent/buy a lighted inspection bore scope.

 

So this was 63K miles on the Comp 306??? When were the springs last replaced?

The cheap Comp cams are CAST so I would say a strong chance of damage. Billet cams can take a little more abuse but even at that I would be taking a closer look.

 

WOW. This Really sucks.

The car runs great other than the noise.

I've been having the worst possible luck with cars lately. My SS hood flew open on me just the other day too = $2,000.

Now I've got to rebuild the damn motor. Sux.

 

Don't really feel like pulling the OPTI and Radiator to check it. I could have the whole motor out by the time I mess with all that stuff.

 

Lol.. seriously? I can do an opti swap in about 1.5 hr start to finish. Not that big a deal.

 

At this point, you're stupid if you don't pull the motor and at least check the bottom end. The metal from those rollers went somewhere.

 

I would definitely pull the cam and inspect everything else. Not worth the risk of running it IMO.

Congrats asshat, you contributed nothing to the thread.

 

Id bet there is more then just cam damage time to do a tear down

 

lol..... he was talking about pulling the cam out, not swaping the opti out...

With the lifters in that condition, i would recommend pulling the oil filter off for starter and cutting it open to see whats inside. I would not run the car anymore untill everything is looked over. Most likly the cam is shot as well as the bearing in the bottom end, once metel fragments are entered into the engine failure is soon to come, even if you changed the oil and cam the damage has already been done.

 

Guys, I'm not trying to be difficult, just saying that it most likely I have to pull the motor either way, so to spend the extra hours pulling the cam out along with the OPTI, I might as well save that effort to pull the whole deal.

So I guess its time for a rebuild. I have a friend with a fresh 396ci LT1 I might just holler at.

 

easy on the name calling hes saying its just not that much more work to check and he would as would I.

 

WTF???
Agreed gregrob is only illustrating the point that it is not that time consuming to pull the cam. Hell thats quite a feat to do it in 1.5 hours flat.

Like others said, that cam is likely a boat anchor and one way or another is likely gonna come out.

I wanna know why this happened. The 306 has the old Comp magum lobes and they are not really prone to cause valve float or bounce unless the springs are just totally shot. What springs are in this motor now?

 

The Springs were totally shot. They had about 60k miles on them. The car ran great though.

It used to have COMP Springs, 918's I believe. I have to check the build sheet to confirm that.

My set-up also has an AFR Hydra Rev Kit too. So the fact that this happened amazes me. Maybe the Rev Kits have a short spring life too?

When I feel the lobes of the cam with my fingers, I cannot feel any damage. But thats not to say there isn't any.

 

I wonder if the rev kit in any way contributed to your problem? I sure would not rule it out.

60K miles on the beehives sure aint helping at all. Do you have a way of measuring the springs rates to further troubleshoot?

 

I don't think the rev kit did any of this damage. The AFR Hydra Rev kit is a great part that eliminates valve float at high rpm, increasing the overall stability of the valvetrain.

At this point I'm over trying to figure out why it happened. I just want to fix it and get the car back on the road. Its been dead for over a year now.

I already have a set of new Patriot Gold Springs on the heads, and a set of new LS7 lifters.

I'm just gonna rebuild the bottom end and forge it, then try again.