hey how about few pictures of your engine setup with turbos, especially if they are under the hatch
need some inspirations for BBC 502-560 ci
I'm caught up with practicality of going with Rajay E13 wheels with water jackets or actually wanting to run a larger twin turbo or single BW 80mm wheel
the engine is going under hatch so mindful of space, heat etc.
was thinking we could use some thermal insulation to reduce the heat around pipework, however need to get the heat out from under hatch

I have looked into using a marine diesel turbo just kicking ideas around. They are a bit pricey compared to the stuff people use on automotive but they are water-jacketed.

not much info on them like maps/ar, inducer, etc since most are oem for cat or cummins or whatever. Some clever math on the engines they are for could get u close

i think it could be done, just not in the plan for my current project

I have a twin turbo 377 Scarab with factory Mercruiser 475 HP turbos. They use a rRayjay EE trim turbo with water cooled heat shields. Gale Bank's and M&W are the only other manufacturers that make water cooled turbine housings. Look online for Carson Burmmett, He makes some twin turbo engines.
https://www.riverdavesplace.com/foru...merlin.144614/

I am also building a pair of twin turbo 454's with the M&W water cooled housings for my 30' Scarab.
This is what the turbos with the water cooled heat shields look like in my 377.

maybe thats the go to put the turbo close to the water cooled exhaust so your not having t deal with heat near the back of engine bay
I have some water cooled turbine housing here off the rotomaster setup and the stainless steel cooling jacket from gale banks rajay setup
I suppose I was trying to clarify whether the Rajay would NOT over spin due to increasing the size of the engine to 502-560 ci

Having looked at the gale banks water cooler exhaust riser they look small, and was thinking that if moved to larger water cooled exhaust like Imco powerflow whether this would be less restrictive, plus whether the rajay would be working more efficiency or spin to fast
The cross section area of the imco exhaust is 2x that of the gale banks exhaust at the top where the turbo T4 bolt pattern is.

Space wise its in favour of Rajay (A/R1.3) or newer BW-S300 turbos (A/R1.0)
manifold wise preference would be imco as they are larger and I have them
Whether to modify the 30 degree riser or adapt them to the centre mount position is realtive to location where you want the turbo
or whether there is other turbo options



imco powerflow plus manifold

I really want a twin turbo setup myself. You can have a hot side 3d printed in inconel with water jackets for any turbo you want. When I am ready I will weld jackets around tial hot sides. If you're not in to all that I would figure out what diesel turbo would work then get a turbo rebuilder to hybrid it with billet compressor wheel. the diesel stuff is just so heavy it will b very laggy.

Phughes69--I'm doing a Gentry twin turbo/twin engine boat. I bought the set but there was NO instructions or diagrams. Where are you getting your water for the intercoolers? Some have said they have a forced water pickup and they only get water while underway, others have tied them to their raw water pump. What's your setup and are you happy with it?

The under hatch look from my last boat, a 30' Checkmate.

check300
looks clean set up
are you running any waste gates on hot side?

I had some 12mm stainless adaptor place laser cut for the imco powerplus manifolds and have ordered 90 degree sch10 S/S elbows, I'll have a crack at fabricating the riser from exhaust manifolds to turbo, will use V-band clamp so can move turbo around to get in correct position. This will push the turbos approx. 8" back from there current on centre location,
Forgot had some aero race/imco /? double skinned water cooled pipes put away few years ago, so they would come off turbo, and get me close to inside of transom. At present from where turbo is mounted I have 1200mm (47") length to transom and pipes are 36" long
at least got the cooling issue covered
pic uploaded shortly

attached pics

was going to run the rajay 301 E13 turbo's as i have 2 brand new turbos here
Not sure whether I'll need the waste gates or not as turbo a reasonable small

PHughes69
are you running any waste gates on turbine side, or any boost valve on inlet
what boost pressure do you see ?
Brett