sleev-les

I have been searching old threads on engine upgrades. I was out the other day and saw that I could only get to 63mph GPS with full tanks of gas and 4 people on board. I love my Bullet, but miss the speed difference in my Tantrum. I have 502's and been thinking about getting some more out of 540's. Problem I'm assuming is the Bravo drives would probably go pretty quick. I also saw a thread where everyone was chatting about a 509 and getting a nice build around 550hp. I'd really love to see 80 again, but on the heavy boat and not going really big, I know that is a tough one. I know with less fuel and 2 people, I can see 70 on a good day now. Could I see mid 70's on a 509? I know thats kind of vague, but wanted to spark the conversation. Also, would it be beneficial and cost effective to use the engines I have to do a rebuild/upgrade (what a typical rebuild would cost by doing something like this). Just gauging potential future plans and would like to hear different thoughts.

Current:
31ft Cigarette Bullet
502's (415hp)
Bravo 1's 1.50 ratio with 24 pitch props (thought they were 26, but was wrong)
Top speed, full fuel and 4 people was 63mph, but light I've seen 70mp

cyrus77

iTrader: (4)

Pretty vague. What boat? Length? Weight? Present HP? Need details.

F-2 Speedy

iTrader: (6)

I had the same discussion with myself, where best to spend the money. I went 540's 509's are cheaper to build and make good power, bore it and new pistons, if you go 540's then it's a new rotating assembly $$$, Im thinking 650-700 a side to get your Cig to 80

Unlimited jd

iTrader: (5)

Freshen the 502's should be able to reuse most of your rotating assembly and buy some afr heads with a good cam, to make 550-575 @ 5500 rpm. Should push that boat right around 80 in the right conditions. 540's would be nice but unless your buying heads cams and rotating assemblies you won't benefit.

Ran-Dom 32

I wouldn't worry about the drives to much, unless you see a lot of airtime & like to do hole shots... Stay away from 5 blades & keep a spare bravo on hand.. that's my strategy

SB

iTrader: (1)

What horsepower 502's do you have now ?

sleev-les

Cyrus, I put some more info in my original post

Ran, I don't do much air time or ever do hole shots. It just has been hard to get used to not being able to hang with other boats and the slower speed.

SB, they are the 415's with Holley 800cfm carbs. The motors have 240 hours on them and run great. I'm looking at the best bang for my buck because if I go to crazy, I could have just bought a boat with bigger power to begin with hahah.. If I could freshen what I have and get descent power like you guys are mentioning above, that would be a great option. Something reliable and can roll a bit faster than I am now. Then take Ran's strategy and have a spare Bravo

JWay

This is a good read on some pretty inexpensive ways to up grade a stock 502.
http://www.offshoreonly.com/forums/d...e-results.html