Against what most will say....if you had a after cooler than 12.7 afr's while not ideal, would not have been death to the motor like this.

Post your timing map and we can look at it.....another friend of mine had a bad ground and a lot of electric noise on his wide band hook up, and so while his AF value's said he was in the high 11's. After correcting his problem we found it was really around mid 13's. :-)

Basically what I am saying is it could be a number of different things.

J. R.

 

Results:

After a little bit of work I've stripped the engine down to the short block. The results were mixed. The #2 piston has a bit of chattering going on on the surface. The other three pistons look great. The #2 bore has two scuff marks midway up on one side. I'm guessing it has about .050mm roughness or so. Definitely out of spec. I can't tell if it's imbedded spark plug material or perhaps the results of piston scuffing. I'm debating a couple options ordered from cheapest to most expensive.

Option 1:
Have head inspected and tanked: 80.00
New OEM Head Gasket: 75.00
Reuse Head Bolts: FREE!
New Spark Plugs: 40.00
Recheck Compression: FREE!
Crossing Fingers: FREE!
Investigate Aftercooler Situation: FREE!
~200.00

Option 2:
Have head inspected and tanked: 80.00
New OEM Head Gasket: 75.00
Reuse Head Bolts: FREE!
New Spark Plugs: 40.00
New OEM Pistons: 160.00
New OEM Rings Set: 33.00
Honing/Polishing Block: 150.00
Investigate Aftercooler Situation: FREE!
~550.00

Option 3:

9.0:1 Pistons or 3mm HG: 300.00 - 600.00
New Rings: 50.00
ARP Head Studs: 160.00
New Spark Plugs: 40.00
Novi 1200 Blower: 2000.00
Sell Novi 1000: -800ish Maybe?
Upgraded Clutch: 500.00
Investigate Aftercooler Situation: FREE!
~2550.00+ Bracket
As far as ignition timing goes, below are the maps I was running at the time of failure.

http://i945.photobucket.com/albums/ad299/j...IgnitionMap.jpg
http://i945.photobucket.com/albums/ad299/j...gnitionMap2.jpg

I'll probably be favoring option 1 or 2 since I'm in the process of buying a house and need to conserve cash for appliances, furniture, and other boring things.

Anyone have feelings on a good standard for how to judge wear to the bore? I can feel a little bit of roughness so my feelings are that it needs to be honed/polished but my compatriots who have done a few low budget rebuilds on lower compression engines urge me to judge it as no concern. I'll post some pics later.

12/06/09 1:46 PM Edit: To Fix Picture Links
12/07/09 7:22 PM Edit: To Update Prices

 

Before I get harassed saying this thread is worthless without pictures. lol.

 

id say now youre stuck with option 3

 

wow, that #3 piston looks really beaten up. Was that the one with the damaged plug? pics of damaged plug?

 

Whow



That has got to be the worst burt piston I have ever seen!

All I can say is sorry dude and good luck on your rebuild!

J

 

i did way worse to my h22 pistons. lemme see if i can dig up a pic.

 

 

check my sweet piston out. oh yeah , thats a darton sleeve that melted a bit. the guy i sold it to had to bore out to 88 or 89 to salvage it.

 

Something has definitely been rattling around in there and beating on that piston or some major detonation on that one. Id assume the first one though. Did an electrode break off the spark plug?