I hate to stir up this hornets nest, but I want to get some ideas and in the mud motor world, I don't know of any better place. I've got a 2008 MB 4000 that's been a great motor but I just want a bit more oomph to move my slow gatortrax hull. For those of you that have run both, would more mods be the best option or should I upgrade to a 4500/5500 black death? For those that will say "get rid of it and get a (insert other brand)", I doubt I'll get away from MB motors (nothing against any of the other brands, just my preference).

Thanks guys

Build it up to a HD 5500 not a BD 5500.

Is the bottom of your boat beat up?
What speed you getting now?

Sorry, what I meant to say was: should I mod out the 4000 or sell it and buy a BD 5500? I am looking for the best bang for my buck...least money for the most power...

Bottom has some dents for sure, but the only true hook is at the base of the transom. Otherwise, IMO it's in pretty good shape. Getting 25-26 now in deep water with light load (1-2 people). Problem is, I usually am loaded down with decoy bags, gear, and 3-4 people during duck season. I haven't run a GPS with a heavy load, but I'd say it's not running over 17 or 18.

do you have the 40 kohler

A 4000 is a stock 35 briggs + Mikuni and Exhaust if I remember correctly.

I would build the motor you have now. The parts to make a 45 mag in addition to a Mikuni make it a 5500 HD
It is stronger than a Black Death 5500 IMO.

ive got a hd 4000 an it has a 40 kohler thats moded up to 52 hp with hardly anything done to it

Yeah, okay

That's a 25% gain, explain "hardly anything"

He must have alot of stickers and an exhaust.

Wadya think CB?

cam and heads (with a little intake work) on what you have now.

^^^^^^^^^^^^^^^ this ^^^^^^^^^^^^^^^^^^^^^

Also, it doesn't take but one bad hook to make a lot of difference. I knocked 2 outta my boat the other day & picked up 2 mph.

heads ported an polished,exhaust,velocity stack on carb an carb rejeted

This is the stuff I was looking for. Thanks for the advice, guys.

Woodie- you're correct, it's a 35 with carb and exhaust.

db- I'll try to knock that hook out and find someone to weld a brace in. I don't trust myself enough to weld aluminum. Do you recommend the iron mountain heads or another brand? Also, do I need to upgrade my valves to match the new heads?

I misread it.