tristanlee85 Posted April 24, 2008 Report Share Posted April 24, 2008 I am a completely idiot and didn't inspect the surface of the head as close to what I thought I did. After running the car for 20 minutes, it lost compression and coolant went into the oil. There is some pitting on the bottom of the head, but the pitting in the picture before is the worst of it all. It's hard to judge by a picture, but I did my best to measure it with some toys from school and it looks like decking the head .020" will remove that. .040" is the max I want to go for compression reasons, but I'd like opinions here. I'd hate to junk the head as it's already ported and polished. http://www.plastikhosting.net/uploads/tristanlee85/turbo/v2/4-23-08/00012.jpg http://www.plastikhosting.net/uploads/tristanlee85/turbo/v2/4-23-08/00013.jpg Quote Link to comment Share on other sites More sharing options...
AJ Posted April 24, 2008 Report Share Posted April 24, 2008 just because it doesn't look that bad doesn't mean its not worse. not only do you have pits but there may be pits deeper than you can see untill its machined. there is also warp issues that may come up. GM also does not recomend machineing the head, it says on SI to replace if pitted, damaged or warped out of spec. because of other tolerances (i.e. timing chain length, chain guides) Quote Link to comment Share on other sites More sharing options...
tristanlee85 Posted April 24, 2008 Author Report Share Posted April 24, 2008 So should I not even worry about trying to have it inspected? I know people that shave up to .050" when building high compression engines and then also shave the timing chain cover down as well to match. Bolt holes still line up. I have another head that came off my engine that was running before and it's perfect. The only problem is it isn't ported and polished like this was so that's a big killer right there. Quote Link to comment Share on other sites More sharing options...
spankis Posted April 24, 2008 Report Share Posted April 24, 2008 Couldn't a tensioner make up for that kind of tiny difference in timing chain length? I really have no experience with any of it, but honestly, wouldn't GM "not recommend" most everything else he's done to the motor?? Quote Link to comment Share on other sites More sharing options...
tristanlee85 Posted April 24, 2008 Author Report Share Posted April 24, 2008 Well the tensioner would make up for it, but I guess what he is saying as far as possible hidden damage, the head is probably junk. Quote Link to comment Share on other sites More sharing options...
ODoyle Posted April 24, 2008 Report Share Posted April 24, 2008 Just P&P the old head and put it on im sure it would be cheaper to that, than to deck a bad head and then port and polish a new one just my .02 Quote Link to comment Share on other sites More sharing options...
Benner Posted April 24, 2008 Report Share Posted April 24, 2008 I wouldn't jump to conclusions. I'd go ahead and have it inspected before deciding to junk it. Quote Link to comment Share on other sites More sharing options...
Dave1647545494 Posted April 24, 2008 Report Share Posted April 24, 2008 yep get it checked out its not super expensive Quote Link to comment Share on other sites More sharing options...
tristanlee85 Posted April 24, 2008 Author Report Share Posted April 24, 2008 I'm dropping it off at Fowler tomorrow so they can inspect it. Thanks guys. Quote Link to comment Share on other sites More sharing options...
tristanlee85 Posted April 25, 2008 Author Report Share Posted April 25, 2008 Fowler looked at it and says it's about .020" to .030" deep at the worst spot. Instead of .040", I told them if they have to go beyond .030" to weld it. He was surprised it ran as long as it did. Quote Link to comment Share on other sites More sharing options...
spankis Posted April 25, 2008 Report Share Posted April 25, 2008 Well, I suppose that deserves a congrats, since you're scrapping the p&p job . Quote Link to comment Share on other sites More sharing options...
koolrayz Posted April 25, 2008 Report Share Posted April 25, 2008 weld it up and then have it machined down. I blew a big hole out mine when I popped a head gasket before. Welded it up and machined it down Quote Link to comment Share on other sites More sharing options...
AJ Posted April 26, 2008 Report Share Posted April 26, 2008 He was surprised it ran as long as it did. that makes 3 of us http://www.pro-touring.com/forum/images/smilies/rollinglaugh.gif Quote Link to comment Share on other sites More sharing options...
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