Best way to get 600+ HP???
 

:readinghelp:My boat has a all stock 380HP 454 Mag EFI with thru-hull. What is the best way to get a reliable 600+ HP. I originally thought of a procharger, but have been thinking of pulling my 454mag and just poking in someone elses crate motor. I have no problem building a motor, but is a 454 bowtie block a good foundation to build a reliable motor, or should I get a big CID motor with more torque?

procharger, whipplecharger...I like that idea. I have never seen a procharger with a closed cooling system though (just wondering to myself).

If your motor is a 454MAG EFI the block is not a Bowtie.
The only naturally aspirated Merc motor with a Bowtie block is the Bulldog. The Mag EFI is a standard Gen VI block.
That doesn't mean it's not a good foundation for a 600hp motor though. You could start with a 4.25 stroker assembly and a good bore will make a good 496 stroker motor that some here have made some really good numbers with.

Dave

I thought there would be more guys pulling for sticking in a crate motor than building one from my 454.

You just have to weigh the cost and end result your after.
Using yours is just one option of many as you'll find out here shortly :drink:

Talk to dean gellner aka Mrhorsepower1 on here, you can make a nice n/a 540 out of your gen VI with some dart pro one heads and get 650 HP out of it. Just my 2 cents

You need a 502 block to make a 540.

Here is what I did. I started with a 454 bored and stroked it to a 489. New exhaust with long risers (no silent choice), RMbuilder custom cam. Good reliable 500HP. If you want more sell what you have and drop in a 540 or 572, start with a Dart or Merlin tall deck. You can easily build 600-650HP with that.

buy a 525

Sell what you have and start from scratch, been there. I did the Procharger and had good results with it but you will be better off starting from scratch with a 540. I added blowers, heads etc to some carbed 454 mags with good results. Both are options, but the 540 will be cheaper and more reliable down the road. A lot of stuff will have to be changed to do the Procharger right. If you build your 454 into more you will have a bunch of parts that you will have to give away. Again start from scratch and build it right.

If you do not decide to supercharge what you have, then just sell it and start over. You will not make close to 600 hp with a 454 NA. If you put a 4.25" crank in it, you will also need rods,,pistons, heads, cam,intake etc. What are you going to reuse........Not much. You will take a running engine that is worth a few dollars and turn it into a pile of used parts that is not worth much. You could make 600 with a Whipple or Procharger on your Mag, or you could start over with a 540 NA and make 600+. I would not build on what you have as it will cost you more in the long run. Hope this helps, Eddie.

I agree with Wahoo. Sell what you have a buy used fully marinized Merc 525's (really 540-550 HP) They will be turnkey, reliable and low installed cost. If you get to 600 HP, you are only leaving about 3 MPH on the table.
What do you want more...the "hunt" or reliability?

http://teaguecustommarine.com//store...products_id=28

Look under "Specs"

That teague motor sure is impressive. Is it possible to have a motor like that with efi or does that mean alot more $$$? Is efi really that much more reliable than efi?

bore your 454 to 468, use a dished piston, .700 lift solid roller cam, intercooler, and cheap ole 250 blower and you will be close to 700HP. The thing is, unless you can pick up all this stuff from a swap meet etc at a huge discount, it is cheaper to order a long block from one of these guys here on the board or just mail them a check for 11-15K and have a bolt in engine.

Remember though, that going from the 454 that you have, to a Dart or Merlin 540, none of the accesories you have will wrok except maybe the sea pump etc.

You will need oil pan, valve covers, just about everything will end up being new.

If you are going to commit to it, then sell the 454 in one whole piece unmolested, and just start from scratch.

Good advice. You mentioned crate motors. Start with this:
https://store.gmperformanceparts.com...rate%20Engines

$12,350 add a marine components---oil pan, starter, carb, flame arrestor, merc/sierra intake thermostat housing, exhaust, remote oil filter (don't forget the oil bypass conversion) and larger marine oil cooler. Add the marine accessories that would not changeover from the 454.

I believe that block already has brass freeze plugs. Valves? Hey, run good fuel and don't rev/run the snot out of it, you will have a solid powerplant for many hours.

600+ HP and plenty of torque for under 20k.

Forgot you have to loose the flexplate and purchase a steel flywheel. Don't forget your MSD 6M w/built-in rev limiter.
This is the block specs.
https://store.gmperformanceparts.com...umber=25534368

ZZ572 motor already has the roller cam and roller rockers. Depending on your marine exhaust choice, may have to purchase different valve covers.

If you are talking about your motor, you do not have a Bowtie block. If you have a Bowtie block laying around you can bore and stroke it to a 540 and as others have said you can easily get 600 HP. Contact Ateco in Waukegon IL. You could work a trade with your engine or sell it outright. They can build you a 540 with the HP you want and do it for about as reasonable as it is going to get. You will need headers, a carb, larger oil cooler and a new prop. You will love the difference.

These GM crate motors are definitely sweet. However if you notice at the bottom it say's "Not intended for marine use"

Yep, they do say that. But I ran my ZZ502 crate for 4 seasons without a glitch. Now it's a 557!!

Feel free to give me a call for a custom qoute. Thanks Laz for your support! I will be calling you the first of the week brother!

So is it possible to make my 454 into a 540 with just a rotating assembly and not a special block?

And the truth shall set you free. One word----Merc.

NO. You need a different block to make a 540. You can make a 496 with a 4.25" crank.
Eddie

For COST reasons wouldnt a procharger be better if it doesnt need to be refreshed? Seems like the cheapest way out...

Yes, you are correct. A Procharger would be the cheapest way to make 600+ hp with his current setup. It will work great and be very reliable if it is set up correctly the first time. That means programming the ecm, upgrading the fuel system, etc.
Eddie

600 hp motors
 

1 st sell your motor, then I would go to classifieds under motors , there are 525 motors in there priced fair they have 520-540 hp , 2 illmors for sale 650 hp(ad says owner wants them gone now) plus others that would be turn key and ready go. Also dont forget next is differnt lower unit / then props/testing

my 2 1/2 cents

Why Are Their So Many Marine Engine ?? Builders on this Forum
 

Gellner and Young both have your best piece of advise and people who can really help you get it right. For 600 - 700Hp reliable marine ENDURANCE performance engine you need just that, not some JEGS, Summit, GM Performance crate or parts basket , garage floor built marine ATTEMPT engine!
Set a reasonable budget as if you don't have the COIN you can't do it right to begin with so don't do it wrong and buy it TWICE!
It kinda scares me when I hear someone threw a crate 502 engine in some boat used it in NY in some small lake for two seasons, probably about 100-120 hours hours tops and now is having to turn it into a 552 something. That's not reliable "ENDURANCE" and sounds like they are into the BUY and BUILD IT TWICE MODE!!

Best Regards,
Ray @ Raylar

GenVI BBC are stout blocks, nothing wrong with a 454. I would do a centrifugal supercharger (procharger, etc.). Should easily make 600hp when you want it, and the rest of the time you won't even notice it's there. Probably not even in boost at cruise. Spend a few extra bucks to do it right.... make sure it's tweaked right, as someone mentioned on here. Maybe frsh headgaskets too etc.

On a side note, I'm all for cubic inches, but I'd rather have a 454 then a 496.
If you want more cubes, I'd bore to 502 rather than stroke to 496.
Also, aren't 454 and 502 the same block? ...9.8" deck/Gen6 BBC.
Both have 4" stroke but the 502= 4.47 bore and 454= 4.25 bore.

502 is a different block it comes with thincker walls to allow for the bigger bore

a stock GM block non bowtie is more than adequate for 600hp
Ive run a few stock GM 454 blocks that have made over 800hp so I would honestly not waste the money on an aftermarket block for the power level your shooting for

you could sell your motor complete and build a 540 inch motor with edelbrock, dart, merlin, afr (any decent aftermarket head) even really worked stock GM heads (but the cost is not really worth it unless you can do all the custom porting yourself) and make 650hp all day long realiably on pump gas without any power adder
its a pretty basic setup
if you need a good shop to build them for you pm me and I can put you in touch with one,
or check out some of the board advertisers on here,
any capable engine shop can build a 650hp 540 inch bbc motor
that combo and power level is really kind of mild