Had a nice back-up 474 that went 9.55 in a 3100 pound car, 8.70's w/250 shot. While freshening, discovered crack in #2 and #4 main webbing. Made the decision to spend $1000 to get it "fixed". They ground material out of the cracks, heated the block up in a huge oven, brazed the cracks. Then machined the bottom of the block flat, bored the mains, bored and sleeved the cam bores.
Ran the motor last half of the season. Ran great, no oil pressure or performance issues (were running a titan pump).
Recently disassembled for inspection: #4 main web cracked up through lifter valley, #4 cam bearing spun - scored cam journal, #3 main bearing and crank journal scored, crank cracked at #3 main journal, #5 & 6 rod bearings wiped. Surprisingly, crank end play was only .010 and #4 thrust bearing looked pretty good, considering. Block AND crank are now both junk.
Was it worth the gamble? In hindsight, no. The block repair company routinely does these kinds of repairs, but those blocks probably aren't subject to this kind of abuse. One more weekend on the racetrack and we would have been picking up pieces.
Now I need a good block that can bore .060.
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