Hi I wonder if anyone can help as I'm in UK.

I have an 87 (I think) TRS drive coupled to a similar vintage 5 litre Volvo Penta small block V8.

The boat is a 1984 Fletcher Arrowbolt 22 feet x 7.5 ft speed boat (UK boat similar to a Scarab 21 Excel in size, weight and performance).

The engine is sweet and has been checked over by a mechanic but it will not go past 4000 rpm with a 19 inch Quicksilver prop (I understand the engine should rev to 4800 rpm it is a carbed engine)

How can I find out the gearing and what size (diameter, pitch etc) prop to use?

I'm concerned whoever re-engined it hasn't matched it up correctly.

Thank you in advance for any help / advice.

Ayuh,..... A frankenbarge,...... Ya don't see Volvo motors with obsolete Mercruiser drives,.....

Are ya Sure it's a TRS,..?? The TRS is a Huge drive for a small speedboat,........