Bulitz

Simple question , can a 454ci 4 bolt block go up to a 540ci ?

Knot 4 Me

No.

Rick G

Simple answer

rev.ronnie

You can increase the stroke to 4.5" and bore it .100" over to get a 535" engine, or bore it .125" to get a 541".

This is assuming you sonic test it and probably use some block filler. Regardless, the rod angle gets a little dicey for an engine running continuous high rpm.

There are other combinations using 4.25" and 4.375" stroke that reduce the rod angle a little and also reduce piston protrusion at BDC. Reliability is more important than a few cubes. One of the most popular engines we build is a 454 bored and stroked to a 496. We just pulled one off the dyno last week that made 624# of torque and 627Hp. All done by 5800 rpm.

Bulitz

Which one you perfare a 540 or 496 ? I mean if you were buliding a motor for your self , you bulid a 540 or a496 ?

Kings11

iTrader: (1)

Going for reliability, geometry and easily available aftermarket kits dictate build a 496.

Bulitz

So why alot of people around there always do a 540 if the 496 is better .i am New in this boat stuff and getting confused

Sunrocket24

iTrader: (1)

People use a 502 block to build a 540, 496 is the normal max for a 454 block.

rev.ronnie

Guys who already have a 502 can simply bore to 4.5" (from 4.466") because the block is thicker (siamesed), and add 1/4" to the stroke to make a 540".

With a 454, you can still go to the 4.25" stroke and have the same rod ratio (1.5 with a 6.385" rod), but you are limited on bore size.

I think, personally, the 496" is an excellent combination, with .250" longer rods. Sure, the 540 will make 45 more HP by the extra cubic inches, but if using the block you have is what is in the plan, it is what it is.

We probably build more 496" engines for street/strip and marine because of the economic factor. Guys already have the blocks, and usually heads too.

Another factor is your drive. Jumping up to 625# of torque is usually the outer limits of most drives that are on production boats.

I have a 496" build on my Facebook page if you want to check it out. PM for my page info.

MILD THUNDER

iTrader: (3)

Yes. A 540 is a 4.25 stroke on a 4.500 bore (.030 over 502 block). A 496 is a 4.25 stroke, on a 4.310 bore (.060 over 454).

A 540 is a great place to go IF you already have a 502, which alot of boats do. You have a 454 block, so installing a 4.25 stroker kit is a great place to go.

BUT, I dont think every 454 needs to go there. If you can only afford either a new rotating assembly, or a new pair of cylinder heads/cam setup, I'd opt for a good set of cylinder heads, good cam combo, on a 454, over a 496 with $hitty heads, and a flat tappet cam. You can make decent power with todays parts off a 454/468 build. I would keep the bore at a minimum, so you have room to rebore down the road. The gain by going from a 4.250 bore to a 4.310 is minimal. I'd rather have the extra meat in the cylinder walls.