Originally Posted by jeffswav (Post 2801583)

If you are planning on keeping the boat and adding further upgrades later. If you are do the exhaust first then do other mods later. It will only yeild you about 1 or 2 mph but exhaust is needed for cam upgrades. I use EMI with long stainless risers.

Originally Posted by RichardCranium572 (Post 2800225)

Whipplecharge it :)

Originally Posted by ricric (Post 2800045)

hello fellow boaters,how can i "bolt on" more horsepower to my stock merc 502 mag (1997 model).? already thinking of relatively inexpensive gil exhuast-any thoughts?what else for quick add-ons?trying to acheive around 450-475 hp range without serious modification.thank you:

Originally Posted by ctuck0659 (Post 2801269)

I'm in the middle of rebuilding my 502's to around 500 h.p. using the set-up recommended by Mark Boos at Precision Marine. There's no real short-cuts or single component upgrade- you're either "all-in" or you're wasting your money. I'll have close to 10K invested in 2 engines when all is said and done, and that's with used Gil's

Originally Posted by Clemat (Post 4806366)

I have a 1998 35 lightning and lost a motor the other night. I’m about to pull both of them out and have them both rebuild just to be safe, what’s your build sheet to be around 500hp?

Originally Posted by Griff (Post 4806383)

This is a 12 year old thread, so I doubt you'll get a response from him.

Here is a 502MPI build thread https://www.offshoreonly.com/forums/...e-results.html