SB, thank you, I appreciate the info.

AKATTACK, thank you for the picture, if you have anymore pictures please post them, they will be very helpful. I'm starting the tear down Monday and doing a mock up of the twin turbos to see if it all fits. The will powder coat to match the colors of the boat.

No, he bought all the gentry stuff..

Ok thanks ! The Gentry Turbostuff. Now,to make the old solidifying stuff in my skull remember. Doh !

Where do I start. The link below will take you to a thread (some pics there) from the current owner of my Scarab who is still running the modified turbo set up. He is on this forum (phughes69) and may have or be able to take some pics for you. You'll see I added intercoolers & wastegates but I still used the carb adaptor although I modified that also. The ports in that carb adaptor and in the intake pipes to the turbos are not for cooling but for actually for warming. Heat is extracted from that carb adaptor & pipes when the fuel atomizes. Without water running through these they get ice cold so the idea was to get thermostat warm water to these to keep the fuel atomized. I've run them both with & without water. Seems only cold days/cold motors that fuel would drop out of the mixture and puddle in the tubes (surging at idle). So my answer to you is, no, you don't have to run water through these if you don't want to.
The original rayjay turbo housings were not water cooled, so there is a separate round plenum wrapped around the turbo bolted to the exhaust flange that cooling water ran through to keep temps down in the engine compt. On mine water exited dry pipes (look at pic). Oil to the turbos came from a tee'd fitting at the back of the motor (oil pressure port), turbo oil drain was via short hose into valve covers.

https://www.offshoreonly.com/forums/...echnology.html

I see that you have already been on PerformanceBoats.com, that is where you will get a lot of good info.
I just did a quick search and came up with this: Gale Banks BBC twin turbo system
Many Campbells from the mid 80's came with the Gale Banks twin turbo set up.

I had one in a Mantra jet boat I ordered in 1977. It was a lot faster than the 455 Olds I had in my previous jet boat. It was a 460 Ford that was rated at 525 HP. It did not have a big low end but it ran good for a jet on the big end. That was pre gps so I don’t have an exact speed. I estimated top speed was low to mid 70’s. It was a lot lot of fun for a 23 year old kid.

Hope this pic comes through & helps (found it on the internet). Forgot to mention if you do have the original turbos from the 475 package the turbo housings have an approx. 3/4" hole in them to bleed off some of the exhaust. This was how Mercruiser regulated the boost. I welded mine shut & put wastegates on.
https://i.imgur.com/KQNtqU3.jpg[/img]

Oh yes, this well help out a lot. Thank you so much.
They are Ray Jay turbos so i assume they are the originals.

Go over to performance boats site and search for obnoxious001. Barry use to work for Banks back in the day and will get you all set up.