socmguy

iTrader: (18)

A friend of mine over-revved his motor and bent a pushrod. We tore the motor down to the rotating assembly after finding the #5 Intake PR was bent. There was minor damage to the lifter guide in the head and a little to the lifter. All of the rockers look fine. The heads will be replaced with fresh 241 castings, hardened PRs, MS4 cam, LS7 lifters, LS2 timing chain, New oil pump, gaskets, and bolts. This car is currently stock with all bolt ons and a tune. The rev limiter was set to 6,500 when tuned which leads me to believe that valve float due to weak stock springs was the culprit. We never heard a knock or any other screeching to indicate a spun bearing. I did not find any metal shavings in the oil either. The timing chain was not broken or stretched. The biggest thing I am concerned about is the small eye brow the valve left on the piston. Can I smoothe this out, and if so with what? You can barely feel it with your finger. I have not dropped the K-member and oil pan yet but I will if my friend decides to upgrade rod bolts. That's all the info I have so far, here are the pics:





What does everyone think?

Ws6man2000

iTrader: (24)

I drove around with 4 deep gashes in 2 of my pistons from the previous owner probally doing the same thing. Still did a heads and cam swap car ran great. Ill see if i can find pics of it. If i were to go back i prob wouldnt do that again. Thats a lot of money to be putting into a motor just for it to blow up after you got it all buttoned up

massls1guy

iTrader: (9)

I would gently take the edge off that eyebrow, I think the piston is OK. While your heads are off how about something a little better than 241's. It's a lot of work to replace the heads and now is a great time to upgrade if you can swing it.

Ws6man2000

iTrader: (24)

ill agree i hated doing the head swap. Def save up and put something else on there.

Halloran

iTrader: (7)

You'll be ok if your pistons look like that. Make damn sure to check your valves and your heads for any damage. I would recommend pulling the valves out just to make sure they aren't bent because two of mine were and a few of the pushrods ovaled out the holes in the heads. Just get a piece of emory cloth and just take down the gouged edge flush with the piston. I think most everyone here has done a bad downshift or revved too high before. My engine looked as follows and ran ok after I replaced the pushrods and heads. Now I'm replacing everything...so go figure.

socmguy

iTrader: (18)

DAMN! the one I posted doesn't look nearly as bad. Why are you rebuilding Halloran? Did the same damaged piston fail? BTW, heads will be replace with low mileage 241s for budget reasons. Heads are fine and will have new PRC duals with retainers and new valve guides.

Halloran

iTrader: (7)

Well, originally I just pulled the motor to replace the oil pan gasket after the LS6 pump install last year. I got the engine out and figured...meh what the hell...

Oh and the pistons ran fine even after the gouges. I didn't notice a bit of difference. I made my own piston reliefs LOL!

LS1C5Vette

iTrader: (11)

6500 rpm redline on stock springs? Ouch.

BlackScreaminMachine

iTrader: (17)

Get a manga flux kit from eastwood. I had a comp cam 987 let lose and put a DECENT gouge in my forged SRP piston. It was fine but I wouldnt put the motor back together w/o doing that 1st.

socmguy

iTrader: (18)

I know. The valve train will be completely upgraded except the rockers and valves.

9000th01ss

iTrader: (10)

Thats why you check PTV clearance and cut the pistons. Was this engine checked?

socmguy

iTrader: (18)

Read the OP one more time.

Beaflag VonRathburg

iTrader: (176)

That's barely even an eyebrow compared to some people have posted before. I wouldn't even worry about it. I would check PtV clearance with the new setup though. Especially if those heads have been milled any.

EDIT: In fact since you have the heads off you probably should flycut the pistons and mill the new heads. That'll give you a nice boost in power and giver you safer PtV clearance than you would with what you currently plan on putting on.

socmguy

iTrader: (18)

It's almost all the way back together. I'll let you all know how it turns out.

Randy WS6

iTrader: (69)

On my old stock motor i eyebrowed all my pistons and it don't hurt any thing ,on some extreme cases you can bend a valve tho ,but from what i see you'll be just fine . but the push rod is bent to hell.

9000th01ss

iTrader: (10)

I understand the OP, and I see nothing about what the PTV clearance was. That means it wasn't checked.
PTVC is .080 to .100 for a reason--to prevent what just happened to this engine.
Slap it back together, don't check a damn thing again.

second_2_none

iTrader: (6)

damn settle down and chill out. this was just a bolt on car and thats it. so if the heads, cam, rockers ect werent changed out then tell me 9000th01ss why the hell you would need to check the ptv clearance?

Randy WS6

iTrader: (69)

Why would you check the piston to valve clearance on a stock motor? Didn't they do that from the factory!!!! Now if it have a aftermarket cam or heads or larger valves then i would say check it for shore. The stock valve spring will not take that kind of rpm with out valve float.

9000th01ss

iTrader: (10)

Settle down? I'm trying to get through to you how important it is to assemble something properly.
OK now I didn't see anything about this being a stock engine at first. It reads what is going back in then says it was stock. I do see that it's being rebuild with an MS4 cam. Better check it, I bet you're not going to are you.
I'll calm down and let you guys waste more money, sound good? I thought you came here looking for help/advice.

second_2_none

iTrader: (6)

dont get me wrong, thats exactly why i came on here, and why i registered on ls1tech period. i understand your trying to help and put in your advice. but you dont see anybody else being an *** about it do you? way to be "that guy".