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RBeyer 08-27-2018 04:28 PM

Boring 454 Mag
 
How far can a 454 Mag be bored?

phragle 08-27-2018 04:54 PM

depends on whats left of the block.

Griff 08-27-2018 04:54 PM

Depends on what Gen and how thick the block is. The older MK4 could go bigger. Gen 5 & 6 are maxed at .060 and lot them can't even go that far.

compedgemarine 08-27-2018 08:30 PM

some of the MK4 blocks are pretty done at .060 depending on the casting number and core shift. some are fine at .070 or so and the older 512 casting numbers are fine at .100 over if they dont have a core shift issue. seems like the later of the MK4 blocks were when they started getting thinner but not positive of that.

RBeyer 08-27-2018 08:40 PM

Thanks all it's a 98 motor and already at .060 I figured the block was probably done.

Rookie 08-27-2018 08:45 PM

I ran a Gen V .070" over (4.320) for 13yrs up to 600HP at @ 6500 at a times with no issues. The engine was built at 420HP by someone else 6yrs prior to me. Not recommending it without the block being checked, but I have done it.

RBeyer 08-27-2018 08:52 PM


Originally Posted by Rookie (Post 4646017)
I ran a Gen V .070" over (4.320) for 13yrs up to 600HP at @ 6500 at a times with no issues. The engine was built at 420HP by someone else 6yrs prior to me. Not recommending it without the block being checked, but I have done it.

This motor would be around 800+ HP Just looking at an old project boat and adding the $$$ up. Ahhhh Toys!

Rookie 08-27-2018 09:08 PM


Originally Posted by RBeyer (Post 4646018)
This motor would be around 800+ HP Just looking at an old project boat and adding the $$$ up. Ahhhh Toys!

The pin would be pulled... Lol

Craney 08-27-2018 09:21 PM

Why not look for a used block on Craigslist.

RBeyer 08-27-2018 09:58 PM


Originally Posted by Craney (Post 4646028)
Why not look for a used block on Craigslist.

I can do that just adding up the cost and considering if I want to buy the boat.

Jonesyfxr 08-29-2018 06:55 PM

Have the bores Nicosil plated to bring back the tolerances. Look into US Chrome for the process.

Rookie 08-29-2018 07:35 PM


Originally Posted by Rookie (Post 4646017)
I ran a Gen V .070" over (4.320) for 13yrs up to 600HP at @ 6500 at a times with no issues. The engine was built at 420HP by someone else 6yrs prior to me. Not recommending it without the block being checked, but I have done it.

I forgot. I just bored a MK IV 0.070" over to put this engines rotating assembly in. I rebuilt my power this spring/summer. My cylinder walls were whooped out after 20yrs. My 0.030" over matching twin was also whooped out just as bad so I don't believe the block was compromised. FYI

getrdunn 08-29-2018 08:36 PM

I'd definately only go as much as needed if your going SC cause of the heat. Like rookie said sonic testing each bore will tell the tale. Fresh water blocks vs salt water blocks can be night and day difference.

Mohavvalley 08-30-2018 11:28 AM

Read this before you decide what your going to do
http://Garage.grumpysperformance.com...ck-cylinder-wa


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