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#1
02-22-2020, 06:02 PM
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455 Mains
On an OEM two-bolt main, 1976 455, is there enough material, size, width or whatever to drill them and tap the block to make them four-bolt mains, or are the mains totally different between the two. Thanks.
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#2
02-22-2020, 06:22 PM
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All the 455 blocks are good. Plenty of room.
Last edited by PAUL K; 02-22-2020 at 06:29 PM. |
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#3
02-23-2020, 10:34 AM
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Quote:
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#4
02-23-2020, 02:57 PM
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It was a thought that dogged me for years as the engine was gradually built up. With my engine now being re-assembled it popped up again. I checked and you are correct. The builder advised that the 2-both main is plenty strong for my build (just shy of 575 hp and tq at the crank)., and especially for the rpms it will see.
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#5
02-24-2020, 07:21 AM
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I have run the 2 bolt mains with studs at the 650 hp level for well over 20 years and never had a issue!
I did fully prep the main caps though, spending some 12 minutes on each cap polishing and rolling over all the sharp edges but for the Bearing parting line. weather your concerned about main cap related failure or not then you should find a balance shop that can balance to less then 3 inch ounces which makes for a huge improvement in loads and strain! Note the black Crank scraper that's worth 12 free HP.
__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! Last edited by steve25; 02-24-2020 at 07:30 AM. |
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#6
02-24-2020, 08:16 PM
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I've been told the same thing by reputable builders so have always just studded the 2-bolt mains. I'm never going to build an engine over 600 HP, so good enough for me.
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---------------------------- '72 Formula 400 Lucerne Blue, Blue Deluxe interior - My first car! '73 Firebird 350/4-speed Black on Black, mix & match. |
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