1997 advantage27

I have a 1997 advantage 27 footer with 502 mercury motor, came with 400hp from factory. the motor trimed up does 59 miles at 5000 rpm.

I like to bump up to 65 to 70 miles per hour, any external modification that can be done on this motor to get more horse power.
Also besides the external modifications , what would give me the best bang for the money to increase hp and speed.

thanks

Edwin

tinman565

Whipple..or Procharger.

blue thunder

Raising the outdrive 2" with a shorty is always the best bang for the buck mph wise. Plus you can easily sell it when done and recoup a good amount of the money spent. You just need to do a little homework up front to make sure your boat will respond well to less prop shaft depth.

pitts1313

Yep, turn your hat around backwards and drop 6k on a blower setup if you're going do it external! 15-20hp = about 1 mph. Flame arrestor, exhaust, carbs,mpi mapping upgrades equate to minutiae gains without a major component like a blower added. Enjoy as is, or blower, don't waste any money on the other.

Jeff P31

Why is it that so many people think that you just buy one or two majic part's and you will go 20 mph faster ? And oh yah I want to do it for less than 1 hundred dollars !

blue thunder

One thousand dollars per mph is my experience on a twin eng boat. 500 on a single.

My boat started in the 60mph range and it has a best now of 94mph. Biggest pop I got was from raising the prop shaft depth 2". Superchargers next. You need to have your engines built for blowers to do blower engines so that gets costly fast.

HTRDLNCN

I picked up ten mph with a weiand 256 at 5lbs on my 502powered 27 Carrera tuned with a wideband AF meter I already had , total cost was around $2500,bought everything on the swap shop on here.It can be done if you can wrench it yourself and are a patient shopper.

pqjack

have one of each for sale for 454/502 mpi...
pm me if interested

CrownHawg

The Advantage while being a solid boat, is not what could be considered a "speed" hull. With roughly 750hp (twins) I'm in the mid 70s. Your 502 could take a whipple fairly well. My 496s, not so much.

ezstriper

yell more power scotty !!! going to need boost to get you there in my opinion..time to call procharger