I have a 32 oceanfarer with 2 x aq170 with 270 stern drives.im thinking of changing to a single engine.anyone got any ideas on what would be the best engine to change to.boat is in .Wales UK.

Volvo Penta KAD 300

I recomend that you still going to have two engines. För manny reasons.
Stafety, handeling.
But one thing is, that the of32 is a beutifull boat, exept when it is to light in the water.

Vp kad300 x 2
Vp kad44 x 2
Vp kad42/43 x 2
Vp aqad41 x 2
Vp aqad40b x 2

Mayby you can compensate with batteries, fueltank possitions...
But the waterline is importen (för me).

The Only alternative if i schuold have one engine is a D6.

Why not one VP V8-430? More power than D6, less emissions, less weight and in Sweden about 330' SEK cheaper.
This is a modern direct injected V8 with catalysts that is cheaper to service that the diesels, delivers more power and even if it might use 10% more fuel it will take more that the engines lifetime to save the 330' on diesel.
A friend of mine swapped out two KAD43 in a Nimbus 32 to two V8-350, got the two engines for same price as one diesel engine would cost. Super happy with low noice, lower installation and service cost.

But to make life easier I would go with dual V6-280, two for same price as the V8-430 and you don't need to rebuild the entire stern. 50% more power than you have today and probably less gas. Your yearly costs with dual will most probably be higher than one single, but I don't know how long it will take to save for the stern rebuild. If you öeave that to professionals in Sweden it's about 100' to just rebuild.

Ich stelle gerade auf 2XAD31A mit 290 DPA mit 130 HP um, ein bekannter von mir hat diese im OF und ist sehr zufrieden. Er soll max 28 Kn machen und marsch 19-21 Kn

I installed two Penta V8 300E in 2015. The boat runs fantastic. Tourque, power and fuel efficient!

Sounds fantastic Thomas!
I guess that the power in a 32 with this setup is awesome.

Did you have any information about fuel consumption at trolling, cruising and max speed with this setup to share with us?
Anyone with a single or dual KAD setup in same boat model that can share same information it would be appreciated.

The things that surprised me most are- acceleration and low fuel consumtion. I guess they go together. It is so quick upp to 25-26 knots. My average consumtion over the 150 hours of operation is 22liters/hour. Very impressive. The performance is very good. With my props the max speed is just north of 40 knots.