Why is #6 spark plug at the wrong angle (is it cross-threaded or is it knock out of position or is it bent)...?

 

That cam should still come out to find out what it is. Might be too close for PTV clearance in the event of a missed shift

 

The plug did not have any damage to the end of it. ???
It must have been cross threaded but it was not threaded in all the way. it was only threaded in 4 to 5 turns.
And the plug was not bent.
Joe

 

I'm about to the point where I am just going to pull the engine and freshen the whole thing up.
Rework the heads, new cam, pistons, rods, turn the crank, ect.
Might as well just start from fresh and put everything back together. I want to have a reliable car and don't want to do this twice.
Any sugesstions for upgrades?
Thinking about going with a 383 stroker kit. but if I do that I will have to get a new crank.
But i'm thinking that might be a good choice. Is the 383 stroker a good street combo?
Who makes a good kit? I would like to find a complete kit.
Thanks, Joe

 

which direction to go?
Bore and sleeve the block and just use the factory crank?
Stroke it to 347 or 383?

Budget is an issue, I have about $4,000 to rebuild this engine.

Hmmm

 

I'd leave the short block as is. You said the oil looked fine, it had good pressure, and there was no metallic shavings in it. Send those heads to TEA for a freshen up and CNC program and with a new cam/lifters/trunion upgraded rockets and a retune .....you will easily kill that four grand budget. 430 ish rear wheel power will move a C5Z out pretty well
You would need to double your budget to even have a chance of chipping off a 383 project
Again, leave that short together, once you release the rod bolts, even to check the bearings, they will often re torque out of round.

 

Beat me to it! I would leave the bottom end alone. They are phenomenal from the factory. I see more rebuilds get blown than high mile factory motors. Your compression test shows the rings are still good.

I would replace the cam with a known entity from Kip, and either get a new pair of heads or see if what you have can be salvaged. Make sure to get the sodium filled valves and beefier pushrods. Your bottom end is fine. Just set up your valve train for good stability and let her rip.

Let kip guide you on lifters, etc. should finish well within budget. Figure $500 for a good tune. $500 for fluids and gaskets, that leaves 3K for heads, timing, cam, etc. also, you can't reuse the stock head bolts. If the ones you pulled aren't ARP, add those to your list.

 

Ok so I didn't get much done today I have been very busy doing other things.
But what I did find was pretty much confirmation of the problem.
Here is a picture of the intake lifter for the #6 cylinder.
The roller has been eat up.

 

Sorry for the crappy cell phone pictures.

Well I was thinking just leave the bottom end in place and freshen up the heads.
Now I now I will have to tear into the bottom end.

So what would you do?
Would you just pull the cam and replace the cam and freshen up the heads?

or a complete rebuild?

This roller lifter was on the intake side and the divit on the top of the piston was on the exhuast side. ?????? is it possible that divit is old? and the heads are ok?

And all of this is from a bad cam? But that wouldn't really explain the low compression on that cylinder would it?

I don't know if I should scratch my head or beat it on a rock.

Joe

 

If it were mine, I would tear the motor completely down and look over everything. Clean everything over multiple times and study every part.

On my new motor I had aftermarket rockers start getting the trunions eaten my the bearings so I was just starting to get metal flakes in the top of the head after 70 miles. I only found this out since I had a lifter tick from new ls7 lifters, otherwise I wouldn't have noticed it for awhile. When I pulled the whole motor apart, 3 flakes made it between the main bearings and the journal. Put some decent grooves in the crank and had to get it polished.

It's a good learning experience tearing apart and putting your motor back together.

 

I would totally check to see if the #6 exhaust valve is bent, like Darth_V8er said with a drill, if so then you would know if that divot is old or not and thus low compression, also need to look at that cam lobe too, that could cause low compression on 6 too, if the intake lobe is worn down, it doesn't look as if it is too much by how the lifter looks, it has no flat spots, but im sure it is all dinged and maybe pitted, but no telling for sure tell you get it out and have a look at it...

And as for the rod and mains those bearings should be looked at.. it was hard to turn over for a reason, whether it be seized bearings or simply bad battery, can't tell now with a new battery since its apart, so the bearings surely need to be looked at, if what the PO meant by it lost power and then couldn't start it, as in it wouldn't turn over then it very well could be bearings

I mean you could wait or even just throw the or a lifter back in slap the head back on with old bolts just for testing (make sure to put the head gasket back on too) and use new or known good battery, turn it over and if spins normally, then prob the bearings are ok..

But yeah if your not wanting to tare the engine out just yet.. you could totally test it that way and have some level of confidence that the bearings are ok.. i would totally take the bottom end apart and have a look see though..

Edit: ha totally was just thinking you could just get a 24mm socket and break over bar and turn your even over by hand, it should be really easy to turn with the heads off.. if it like sticks then finally turns and gets a bit easier.. then after stopping if you try to turn it again and its hard.. id say bearings seized..

but yeah it should be really easy to turn with the heads off even should even be able to turn it with your hands on the harmonic balancer.. yeah if its a manual put it in neutral.. the torque converter should hold and resistance .. :end Edit.

And as for the bank 2 head #6 plug hole is clearly messed up and i have no idea how it got that way, i guess someone cross threaded it and then chased it and it ended up crooked, but yeah idk, if it happen from a valve head breaking or something in the cylinder.. the combustion chamber would be all pitted and dinged up if not, it should be at lest by the plug bung..

neways yeah peace man

 

Replied in your other thread. My guess is its part of a batch of bad cams that had a bad heat treatment on it. Others have seen similar issues. You can search for posts by Damian who runs Spartan Performance. Fix the bent valve, freshen up the motor with new rings and bearings go with a 224/228 112 cam and call it a day. If you want to get crazy have the stock heads CNC'd or leave them like they are and you should still be in the 450 RWHP with stock heads. If the car is already tuned, then you may want to see what cam was already in it otherwise you may have to have the car re-tuned.