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Discussion Starter · #1 ·
I'm thinking of building a 427 iron block motor instead of my previously planned 402 LS2 block based motor. Here's what I need to know.

1. Is it possible to bore a 6.0 iron block enough to built it into a 427 without having to sleeve the cylinders? I was thinking that the sleeving was only required on an aluminum block.

2. With the above being a "yes", who sells the rotating assemblies for the 427?

Thanks for your help in advance.
 

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Norman:
I know 421 seems to be a magic number for iron blocks, and a number of builders are doing THOSE. Seems to me Lunati had a rotating assembly to suit, but as to overbore, 'fraid you'll need to talk to the "experts"... my "Power" knowledge stops at "Pro", NOT "expert"... :sneaky: :lol:
Good Luck, my friend!
 

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PerforminNorman said:
2. With the above being a "yes", who sells the rotating assemblies for the 427?

[/SIZE] [/COLOR]

Lunati :z:
 

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It's not that common to build a 427 with an iron block. Only a small fraction of the iron blocks are good enough to be bored 60 over to 4.060" (no sleeves in iron block). They need to be sonic tested first for sure.

You also have to go with a 4.125" crank instead of the 4.000" crank since you can't get to a 4.125" bore with an iron block (on a sleeved block you can get 4.125" bore for 427ci with only a 4.000" crank.) The longer stroke will be more likely to burn oil (high piston velocity). Spring for the sleeved darton block!



PerforminNorman said:
I'm thinking of building a 427 iron block motor instead of my previously planned 402 LS2 block based motor. Here's what I need to know.

1. Is it possible to bore a 6.0 iron block enough to built it into a 427 without having to sleeve the cylinders? I was thinking that the sleeving was only required on an aluminum block.

2. With the above being a "yes", who sells the rotating assemblies for the 427?

Thanks for your help in advance.
 

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Discussion Starter · #5 ·
torchedZ said:
It's not that common to build a 427 with an iron block. Only a small fraction of the iron blocks are good enough to be bored 60 over to 4.060" (no sleeves in iron block). They need to be sonic tested first for sure.

You also have to go with a 4.125" crank instead of the 4.000" crank since you can't get to a 4.125" bore with an iron block (on a sleeved block you can get 4.125" bore for 427ci with only a 4.000" crank.) The longer stroke will be more likely to burn oil (high piston velocity). Spring for the sleeved darton block!

Great info. Thank's so much.
 

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Because of the block deal, 421 may be the "safe" way to go, Norman, but talk with an "experienced" Gen III builder. I know of one local dude who's redone his 421 "Solo" F-car engine a few times...
 

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torchedZ said:
It's not that common to build a 427 with an iron block. Only a small fraction of the iron blocks are good enough to be bored 60 over to 4.060" (no sleeves in iron block). They need to be sonic tested first for sure.

You also have to go with a 4.125" crank instead of the 4.000" crank since you can't get to a 4.125" bore with an iron block (on a sleeved block you can get 4.125" bore for 427ci with only a 4.000" crank.) The longer stroke will be more likely to burn oil (high piston velocity). Spring for the sleeved darton block!

He's correct. You're going to want to go for the dry-sleeved LS2, the wet-sleeved LS1/LS6 or a C5R to achieve 427 or larger. The big downside of the iron block is you are going to add roughly 60lbs to your nose which might be ok for a drag car, but I sure wouldn't want to do it.

My .02
 
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