Shit happens. Motor is coming out.
08-03-2006, 12:02 AM
#21
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It is hard to believe but we will see. 8.9:1 comp, forged pistons, 10psi boost and only 16* of timing. It should have held up fine. Maybe one of the injectors got trash in it and one cyl went lean and burnt a piston?
08-03-2006, 12:16 AM
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Originally Posted by mjhoward
It is hard to believe but we will see. 8.9:1 comp, forged pistons, 10psi boost and only 16* of timing. It should have held up fine. Maybe one of the injectors got trash in it and one cyl went lean and burnt a piston?
The more I read, the more I think I need .........
, I feel for ya man
08-03-2006, 12:43 AM
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Originally Posted by SBTork
The more I read, the more I think I need ......... , I feel for ya man
, I feel for ya man
Thanks for the support 
. I had to go to work to make some OT and pay for the next parts so I had to sober up 
. I almost had the engine out when work called. I'll have it torn down tomorrow.
08-03-2006, 03:06 PM
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Originally Posted by 1slow01Z71
Im guessing she had the same facial expression as when we were sitting in the dining room and you told her you were building a new motor since the 4.8 was dead
Looks like you are having the same luck as me. I think your shop is cursed. Carrier your truck is next 
Looks like you are having the same luck as me. I think your shop is cursed. Carrier your truck is next
If it does I guess I'll be telling the wife how it only makes sense to go forged on the 408.
08-03-2006, 03:54 PM
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Originally Posted by 2bseen
damn Mark I have a hangover from having too many for ya. I had #2 plug electrode melted and pulled #2 piston and it is gaulded really bad. Block will need boring. I didn't bore it last time. The cyls looked good but it was a gm warranty motor and was missing one of the pistons (either #1 or #2 i can't remember) I just honed it and put it back together. I have a feeling the original issue was on #2 cyl, go figure
. I didn't check the cyl bore size since I was in a hurry but i did check the bearing tolerances really close. I guess it just slipped my mind. I did a rough check on it and #2 cyl is .0005-.001" smaller than another one I checked to compare it to. Another one of my "getting in a hurry" screw ups it looks like. Well, since it has to be bored then that means new pistons, and that would mean rebalance, if im going to do all that I might as well get a 4.00 crank right? 
08-03-2006, 08:07 PM
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kinda thinking that hot lapping it on the dyno 15 times might have gaulded the piston. The guy that runs the dyno drives the cars himself and he pretty much shuts them down right after each pull and doesn't allow much time for water to circulate. Heat soak could have been the culprit.
But there is always an upside to everything....this explains why it was 50-100 hp down on power from what it should have been on all 8 cyls.
But there is always an upside to everything....this explains why it was 50-100 hp down on power from what it should have been on all 8 cyls.