98 454Mag questions on HP upgrades
 

I'm eather thinking of having a motor built next year witch will make about 500 hp. Or have the motor I have 454Mag worked on to make 450 to 500 hp.

Talked to Derebery marine on having a motor built would cost about $12000.

My question is would it be feasable to just have the 454Mag worked on and be happy with that? I haven't got any quotes on what it would cost to do it yet.

I'm sure alot of people out there already have done this!

Can someone shed some light on what it would take and cost to upgrade the 454Mag from 385 hp to around 450 to 500 hp?

Thanks

Russ

Tyler Crocket can add the needed power by a cam swap, cylinder head work, and remap the ECM, adds about 100 HP and cost a LOT LESS than the complete engine you are looking at
www.crockettmarineengines.com

Try crocket It's not like you are looking to go from 60 Mph to 90 mph save the money

Tyler upgraded my carbureted 7.4 L last year and the result was 464 HP and 510 lb-ft. of torque on the dyno. Seems to be about the range of power you are considering. The engine ran flawlessly last summer.

Because I started with the low power 7.4L, your cost would be much lower than mine because you already have the forged crank and pistons and better rods. I replaced my entire reciprocating assembly with Eagle forged crank and H-beam rods and forged pistons. I also had him put larger 2.25" REV severe duty intake valves and inconel exhaust valves in the Edelbrock oval port RPM heads I already owned, to which I added the Edelbrock RPM intake manifold. Tyler installed a custom hydraulic roller cam, Gary Williams modified 750 Holley carburetor and MSD ignition. Many of these upgrade were referenced in the April 2000 issue of Hot Boat Magazine, page 98 article on a 502 EFI upgrade.

Has anyone done this upgrade?

Does anyone know how much that package would cost from Crocket? Sent them an email about it.

If I did do the upgrade what else would need to be changed besides the prop?

What did it cost to upgrade the 7.4?

What would labor cost on something like this?

Anyone know some good mechanics in the Dallas erea?

Thanks,

Russ

Russ, I've done several projects like you are looking at. I'm located just outside of Austin. You should be able to get the results you're looking for without replacing your engine. Give me a call. I'd be glad to advise you or can handle the whole job for you. 830-6935591

Bob Lloyd

Russ,

Are you the Russ that has a Baja and hung out some on Lewisville last year with some Crownline folks? If you're who I'm thinking of, you know or met, several people that had or have had work done by Bob at Full Throttle Marine (bobl). You may be surprised at what Bob can do with your 454 MAG. Very much worth at least calling and talking to him.

It's only about 4 1/2 to 5 hours drive and well worth it.

I have made those upgrades to my 454 mag efi. Sent my heads out to tyler crocket and did the rest myself. I also added stainless marine exhaust. I would say I gained about 3-4 mph in top end on a 24 outlaw. Besides the heads, I replaced cam, lifters, pushrods, rocker arms, fuel pressure regulator, flame arrestor, ecm remap, and exhaust. While I had to motor apart, I also honed the cylinders, new rings and bearings. The motor runs great, but never had it on a dyno. I'm guessing around 450 - 460 hp.

Allen

Hey Jim,

Yes I'm the guy with the Baja. My whole scenero changed though won't have the 454Mag now. So I'm talking with Bob Loyd about building me something BIG. Since the boat I'm getting only has a 6.2 in it.
Then again Bob is getting some pretty good HP out of a 6.2. (over 400 HP).But that wouldn't be enough for me eather.

Talked to Derebery Marine about trading the 6.2 with no hours on it for a 502 and they where going to give me $4500 for it. Then still charge me $4000 for the 502 without install! Then I would still have to build the 502 up from there to get to where I want to be. And for a 500 HP motor they want $12000 not installed.

So I'm talking with Bob on what he can do for me to get me in the 500 HP to 600 HP range. That 555 Merlin on his web site looks pretty good at 650 HP. http://www.fullthrottlemarine.com/


See you at the lake

Russ

By the way I did get a reply from Tyler Crocket about adding 100 HP to the 454 Mag.

His reply:
I do have a kit we put guide liners in the heads and install bigger valves,cam, roller rockers, Ex, pushrods, program the ECU, timing chain, gasket set, fuel cooler, fuel pump and regulator, valve springs, flame arrester.

Parts are about 4000.00 and machine shop labor is 500.00 and 1200.00 labor if you want us to install kit.


Russ