naviathan Posted October 13, 2007 Share Posted October 13, 2007 Not sure how in the hell this happened, but I have nice little smiley faces in each of my pistons from the exhaust valves. Doesn't look bad, the valves are probably bent although they look fine and the indents in the pistons are only about .020" deep or less. I can't figure it out, but it had to be from when I had the car running as the ones where the cam lobes from the schneider cam didn't wear out are shiny indicating they were hitting the whole time. Now I did notice where I had marked the chain last time wasn't lining up this time, it was on the opposite side of the cam gear from the #1 marker, but everything else was lined up though. Piston is at TDC, both #1 and #2 lobes were up and the crank pulley mark was at 0 just like last time. Is it possible my chain might have skipped a few teeth during the initial startup when the pump was dry? No oil pressure would cause the tensioner to not put tension on the chain. In either case the valves I pulled out were .015" shorter than the valves from my P90 and .080" shorter than the stainless steel valves I bought for my performance N series head I was hoping to build one day... My head hurts... Quote Link to comment Share on other sites More sharing options...
z-ya Posted October 13, 2007 Share Posted October 13, 2007 I did a similar thing putting a head back on. I didn't get the cam timing right. The engine ran, but was like a slug. Then I checked the can timing and it was off at least a few links. When I pulled the head I got the same smilies you've got. All but 3 valves were lightly bent, but the guides were OK. Yea, it sucked, but I got it back together just in time to blow some ring lands detonating under boost. So that motor is totally toast. It's only money..... Quote Link to comment Share on other sites More sharing options...
naviathan Posted October 19, 2007 Author Share Posted October 19, 2007 I remarked the chain so I should be good to go when I put it back together this time around. I have new exhaust valves coming in from SI on Monday so I should have everything back by Wednesday and hopefully get it most of the way back together before the weekend. Quote Link to comment Share on other sites More sharing options...
naviathan Posted October 27, 2007 Author Share Posted October 27, 2007 Well my machinist decided he didn't want to ruin a set of stainless polished valves so he went ahead and ordered a new set at stock size for the exhaust from SI. The head is back on the car, no problems getting it together and getting valve lash set, it's back to stock sized lash pads now. Who in their right mind would put P90 valves in an N42 head??? Someone must have done it because the seats had been changed to steel before I got it. Anyhow, there's no accounting for other peoples actions I guess. Quote Link to comment Share on other sites More sharing options...
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