by 4agtepwr » Thu Apr 11, 2013 9:04 pm
Those scores are from foreign material making its way into the engine via the air intake or the engine not being cleaned properly when it was assembled , not the result of a heat related seizure.
A heat seizure will show across the pin bosses of the piston as that's where the most material is in the piston so with excessive heat that's where there is the most expansion.
Looking at that block i'd say it's due to it being so corroded, that has weakened the bore significantly. Boost is kind of irrelevant, cylinder pressure isn't but if it was making 240hp on 18 psi then cylinder pressure wouldn't have been that high. I'm going to say it was a tired old block that hasn't been looked after.
Current ride: Sweeeeet Hiace. 3L power!!!!
Project: AW11 4agte, 410kw 555hp on 26psi
11.1 @ 125.5mph with more to come, As seen in Aug 2011 Performance Car, haha
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