bigdsz

iTrader: (1)

I've got some 4.8/5.3L Absolute Speed heads with combustion chambers that have been CNC'd. I always thought the chambers were 65cc. The machinist reworking the heads told me they were 69cc, so I had him mill .022 off, to bring me to like 66cc.I'm having a 408 built so I didn't want to go any smaller. Now I'm worried that the machinist could have measured wrong and the chambers are now actually like 62cc making the CR too high. Does anyone know what the original cc was and how much CNCing might take off? I've already done a search, no luck. Also, what would the CR be with a 4.00"bore with 62 and 66 cc chambers? Thanks.

N4cer

iTrader: (11)

Stock 5.3L heads are like 61cc.
My old AS stage 2.5 5.3L heads cc'd out to 66cc (stock 241 casting size).
Sucks since most folks plan on increased compression from 5.3L heads.

bigdsz

iTrader: (1)

This is what I don't understand, if the 862's stock are 61cc how did mine get to 69cc? I wouldn't think Jay's CNC program would have cut more than 3 to 4cc to unshroud the valves. I guess I'd better take a head to another shop to make sure they were cc'd right.

craze4speed

iTrader: (12)

when they ported the conbustion chamber they could have took that much off easily it wouldnt surprise me if it did