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litew8 · 11-30-2013, 03:46 PM

More info on previous topic:

"Main caps.. Chevy 350.. Has 5 caps that holds the crank shaft into block.. Each cap has a bearing.

A 2 bolt block, all 5 caps has 2 bolts per cap bolting it to block

1 4 bolt block, the front and rear caps are still 2 bolts per cap.. The 3 center caps has 4 bolts per cap holding them to block.

Now yes, the 4 bolts in the center caps are stronger, but a few things the other people forgot (or didnt know) to tell you is..

Theres very little room on each side of main web for that extra bolt.. By drilling and tapping that second hole on each side, you now have a weaker main web, and oil pan rail.. The crank aint gonna go anywhere but those outter bolt holes may crack..

Next, the weakest part of the main cap setup is still there and now has less surface aera.. The cap it's self.. 4 bolt and 2 bolt caps (unless you have one of GM's stock 67-71 375 HP engines) are made from the same gray iron."

11-30-2013, 03:46 PM	#52
litew8 Registered User Join Date: Jul 2011 Location: Des Moines, Iowa Posts: 3,016	Re: For Gramps (1970 C20 RestoMod) More info on previous topic: "Main caps.. Chevy 350.. Has 5 caps that holds the crank shaft into block.. Each cap has a bearing. A 2 bolt block, all 5 caps has 2 bolts per cap bolting it to block 1 4 bolt block, the front and rear caps are still 2 bolts per cap.. The 3 center caps has 4 bolts per cap holding them to block. Now yes, the 4 bolts in the center caps are stronger, but a few things the other people forgot (or didnt know) to tell you is.. Theres very little room on each side of main web for that extra bolt.. By drilling and tapping that second hole on each side, you now have a weaker main web, and oil pan rail.. The crank aint gonna go anywhere but those outter bolt holes may crack.. Next, the weakest part of the main cap setup is still there and now has less surface aera.. The cap it's self.. 4 bolt and 2 bolt caps (unless you have one of GM's stock 67-71 375 HP engines) are made from the same gray iron." __________________ project: "my happy mess"