Valves hit pistons - Questions
01-07-2009, 10:39 PM
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Valves hit pistons - Questions LS2 -
Timing chain broke and caused the valves to hit the pistons. A couple of the pistons are hit hard enough to feel the roughness of metal sticking up a little.
1) When the valves hit the pistons are the pistons ok to reuse? Can/should they be machined or grinded down?
2) When the valves hit the pistons does it send a shock through the crank and or bearings that would cause a concern for reusing it?
Plan is to buy a set of TFS heads and bolt it to the existing block. Just want to make sure the cam/pistons/crank, etc are ok to reuse.
Timing chain broke and caused the valves to hit the pistons. A couple of the pistons are hit hard enough to feel the roughness of metal sticking up a little.
1) When the valves hit the pistons are the pistons ok to reuse? Can/should they be machined or grinded down?
2) When the valves hit the pistons does it send a shock through the crank and or bearings that would cause a concern for reusing it?
Plan is to buy a set of TFS heads and bolt it to the existing block. Just want to make sure the cam/pistons/crank, etc are ok to reuse.
01-07-2009, 11:22 PM
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LS2 -
Timing chain broke and caused the valves to hit the pistons. A couple of the pistons are hit hard enough to feel the roughness of metal sticking up a little.
1) When the valves hit the pistons are the pistons ok to reuse? Can/should they be machined or grinded down?
2) When the valves hit the pistons does it send a shock through the crank and or bearings that would cause a concern for reusing it?
Plan is to buy a set of TFS heads and bolt it to the existing block. Just want to make sure the cam/pistons/crank, etc are ok to reuse.
Timing chain broke and caused the valves to hit the pistons. A couple of the pistons are hit hard enough to feel the roughness of metal sticking up a little.
1) When the valves hit the pistons are the pistons ok to reuse? Can/should they be machined or grinded down?
2) When the valves hit the pistons does it send a shock through the crank and or bearings that would cause a concern for reusing it?
Plan is to buy a set of TFS heads and bolt it to the existing block. Just want to make sure the cam/pistons/crank, etc are ok to reuse.
01-08-2009, 10:02 PM
#6
Ghetto flycut
Now you are ready to clear that Texas Giant
Seems like several GenIV engines recently have busted TC's under suspicious circumstances running UD pulleys.
However, you should be fine if you lightly take the sharp edges off the piston eyebrows. Valves will bend before rods so I think you are ok there. So clean'em up, throw those TFS on there with a nice cam and go have some fun. Pics of the carnage would be NICE though
After reading about this I would definitely go back to a OEM balancer or better get an ATI Super Damper. They have a 10% UD and heard they just released a 25% UD not even in thir catalog yet. Those and maybe a March would be the ONLY ones I would consider. Beat on it hard and ATI is the ONLY choice I think. I guess there is a good reason so many in NASCAR run them
Sounds like you were lucky and making the best out of a tough break
GOOD LUCK
Now you are ready to clear that Texas Giant Seems like several GenIV engines recently have busted TC's under suspicious circumstances running UD pulleys.
However, you should be fine if you lightly take the sharp edges off the piston eyebrows. Valves will bend before rods so I think you are ok there. So clean'em up, throw those TFS on there with a nice cam and go have some fun. Pics of the carnage would be NICE though
After reading about this I would definitely go back to a OEM balancer or better get an ATI Super Damper. They have a 10% UD and heard they just released a 25% UD not even in thir catalog yet. Those and maybe a March would be the ONLY ones I would consider. Beat on it hard and ATI is the ONLY choice I think. I guess there is a good reason so many in NASCAR run them
Sounds like you were lucky and making the best out of a tough break
GOOD LUCK
Last edited by SOMbitch; 01-08-2009 at 10:11 PM.
