Find a 502 and do a 540. You would be much better off and less money.

I really don't know much about 502 tuning..
Also some sort of Raylar alike kits with alu heads, intake manifolds, strokers, and so?

Why do you think 502 is better than 496?

Hello Goran271,

a frend have a complet Raylar setup with 600HP for sale. We are in germany, near Frankfurt. Let me now if, if you need something.

that would be nice, I will send you my number in PM so we can talk over whatsapp over that

Goran,
Check pm.

So a little bit more info on my problems here

I bought another boat (2001 29 Fever, and installing 525 EFI in it), but still trying to resolve this problem on my old 271..

So my 496 is a 2001. HO as I found out thru engine number, but my PCM is 2006 from BASE model.
so it is detuned. But also numbers do not match as I think.. Bravo 1 1:1,50, Mirage 23P, 4650 RPM I got 49.8 mph GPS..
On mercury site I calculated prop slip of 26%.. This is not good as far as I know...

Prop looks very good, clean, no damage.

Only thing that may be wrong is rubber damper slipping a little bit?


I also bought parts to refresh the complete engine (piston rings, gasket set, main and big end bearings, little head porting, Raylar cam and lifter set)
I would like to see after all that is done including pcm reprogram and tune for raylar around 450-460 hp
upgrade to 25-26P should get me @ 65 GPS on 5100 if nothing slips

Am I on a good way, or I got all things wrong?