snapmorgan

iTrader: (2)

I am sure this has been asked many times, but here we go. I just purchased a second hand 27' Advantage, 454 mag, efi , Bravo1. This boat is a slug down low. Runs 56mph @ 4800 rpm WOT.
My question is, what is everyone's opinion on how to add some trouble free HP to this engine without breaking the bank. Supercharger, Whipple or punch it out to a 489 and put some good heads on it. I have been involved in automotive performance for many years, but this will be my first attempt at a boat.
I assume that anything I do will require an exhaust upgrade, injectors and an ECU reprogram.

Thanks in advance, Joe


P.S. I am not looking to run 100mph, just give it some acceptable performance.

picklenjim

Stroke it and bore it .060 over if you want to add some trouble free extra performance.

FlyinZX14

The EFI on that engine isnt much good for much more than stock. Converting to a carb with a good intake will almost be necessary if you start messing with it. Since your changing the intake, why not put a blower on it...

mike11

Gotta be more specific as to what defines breaking the bank and how much is more hp?

Procharger kit will really wake it up, n nothing required if doing a 5psi kit, stock inj,pcm map and exhaust go beyond 5 and those are required. If your not opposed to premium fuel bump the compression and do a MILD cam upgrade within the limits of your exhaust and mapping.

Can pick up some from heads n compression too but only so much cause the intakes n plenums on these are what they are n they arent the best for much over stock.

Then theres the heads intake carb convert or new efi.
The sky is the limit but your budget is where it stops.

I always ask customers what their hp and mph goal is and then work a pkg and plan for it. Sometimes it fits the budget n sometimes not. But everything's clear upfront and moneys not spent coming up short or being disappointed with results.

snapmorgan

iTrader: (2)

I would like to wake up the bottom end without sacrificing any top end speed. Maybe add 50-100 hp. If I can get 200-400 rpm extra at WOT with current prop setup, I would be happy also.

Can I do this with 5psi? Spend 5K or so?

Thanks

jeffswav

Get a full roller setup from RMbuilder. You will also need performance exhaust with long risers. You could Bore & Stroke it to 489 or 496. Recal your PCM to match components.

srx 780

snapmorgan, is it purple with checkered flag on side?

Young Performance

A Procharger or Whipple would both really wake it up. In addition to the supercharger, you will need to program the ecm, upgrade the fuel system and head gaskets, at a minimum. Plan to spend about 7k for the Procharger installed and about 9K for the Whipple. These are rough prices but will give you an idea of what you are looking at.
Personally, I would not spend the money to stroke what you have. That same crank will go into a 502 block and give you an extra 50+ ci. In order to make you hp goals, you will need heads, cam, intake, etc. You will spend about the same as the supercharger and still not make the same power. Just a thought. Give me a shout if I can help in any way.
Eddie

snapmorgan

iTrader: (2)

It is purple, but no checkered flag. Bought it in Virginia 2 weeks ago.

snapmorgan

iTrader: (2)

I appreciate everyone's input so far. I am a mechanic and own a truck repair shop, so i could install a blower in house. I also have a very good machine shop not too far from here that can handle block, balancing, head work with a pretty quick turnaround time. Any more suggestions? So far everyone has had a different opinion. Where would be a good source to buy a blower at jobber price?

Thanks, Joe