fixed head now what?

[pyro]

Hey,
As some of you know I bent all of my exhaust valves. They all crashed into the pistons because of a missshift. Anyways i got the head squaird away with all new exhaust valves reground intakes and seats on all of the valves. I had them put a some shims on all of the valve springs to bring up the spring tention a little bit. Im doing a head gasket kit and putting arp head studs in. Im also repplaceing the thermostat and oil and coolant. Does anyone have anything elts i should repplace while im there?

[SnakeyesTx]

When you said crashed into the pistons... do you mean they literally hit them and left marks in them? If they left chunks or imprints, you better just go ahead and change those too otherwise you're inviting that area to become a hot-spot and break apart.

[yaofeng]

I don't agree with the logic. The piston may have been damaged due to mechnical impact. The dented area won't get any hotter than undented part.

[632 Regal]

unless there are sharp edges.
The dented area won't get any hotter than undented part.

[nizmainiac]

better safe than sorry, you'll rue it if you don't do it now while its all in bits

[GoldenOne]

did your valves make any artistic shapes like my buddy's?

http://free.300zxclub.com/files/2/BentValves/HP%20026.jpg
http://free.300zxclub.com/files/2/BentValves/HP%20025.jpg

[GoldenOne]

oh, and btw, just for precautionary measures replace all the spark plugs

[SnakeyesTx]

Its pretty simple, thinner metal, weakest link to combustion heat and compression. If I still have the pictures, I'll be glad to show you what a 401 V-8 looks like after such a thing happens :(

[SnakeyesTx]

THAT is freakin art! o_O

[pyro]

They did scrach the pistons and took a little ding off of one but i sanded them down flat and smoothed em out so there shouln't be a problem.

[Scott H]

with what? how much did you take off? are you sure of the integrity of the piston? you have less material now so there is going to be more heat. Your compression ratio will change as a result, and each cylinder is not going to be as equal as possible as intended by original manufacturing. What exactly do you mean by "ding"

Why are you using arp head studs? Is there something wrong with the stock hardware?


They did scrach the pistons and took a little ding off of one but i sanded them down flat and smoothed em out so there shouln't be a problem.

[pyro]

well... the head bolts are torque to yield and they are 11.95 a piece
so arp is chaper

[ricola]

I've notched pistons for valve clearence. There is no issue if you smooth the edges. I assume this is a street engine. The small mark left in a factory forged piston will not effect your engine. Even with an occasional spirited romp.

[Bill R.]

brittle than a forged piston. As badly bent as some of those valves are , the damage to the pistons could be extensive.... I'd also think about checking the rod bearings after a smack like that.




I've notched pistons for valve clearence. There is no issue if you smooth the edges. I assume this is a street engine. The small mark left in a factory forged piston will not effect your engine. Even with an occasional spirited romp.

[pyro]

my valves don't look like that... all it did was skuffed em up a little bit... and one had a diny ding in it.

[pyro]

regurdless the pistons arnt being repplaced i was just wondering if there was anything top end related that should be cleand/repplaced

Id buy a new motor for the price of getting new pistons

[pyro]

well got everything back together accept 5 valve cover bolts. And ran it for 3 minuts and then shut it off and draind the oil and filld it back up. now i have to bleed and change the coolent out. the only thing im worried about is the head not haveing water in it and getting hot but i guess there is nothign i can do but run it and keep adding water.

[joshua43214]

As long as the dents are not too deep, I would not worry about the pistons. If some metal was swedged up, I would smooth any sharp edges out or you may get detonation.

Good luck, tell us how it worked out