Had a 508 BBC built all top notch internal. Broadax race right heads. the motor was set to 8 to 1 compression. Plan on running 16 LBS boost. One little detail I'm putting in a 19' Crusader Berkley jet boat had pump built to support up to 700 HP. I'm at the point of putting together the exhaust system and intake. As for the exhaust manifolds I'm running a set of the Gail Banks water cooled rail and case. After that the exhaust enters a 3" stainless tube and is feed to base of the turbo's each side. The turbos are from the early 80's the brand is RayJay. They were brand new still in the box paper work and all. The exhaust housing on them is water jacketed basically they are intended for marine application. From information I found on them and info in box they are capable of about 16 pounds boost. Running two of them one on each side. Been on Ebay looking at wastegates and seem to be lookin g at the Tial units. Not wanting to brake the bank they seam to be decent. Will be installing two of them on the exhaust elbows. They are 44mm and will be running a manual boost controller. As for BOV Tial has 50mm units and would run two of them also more for safety as in two. These would feed two water cooled heat exchangers to cool the intake charge then into a power hat that sits on top of an FI-Tech 1200 HP EFI unit. It can handle up to 25 pounds of boost but I only plan on running around 16 pounds. Not looking to brake any world records just wanna play and have fun. Oh the cam was built by Ultradyne cams and built to suit my build and application, hydraulic roller 610 lift mild application. Basically looking for feed back on build and suggestions from people that know turbos. I've been in the car racing most of my life and know that pretty well. I have a 1970 Nova true SS with and L78 396 stroked to a 438 running the 800 HP EFI unit from FI-Tech puts 532 to the ground Tremic 5 speed 411 gears, 720 Ultradyne solid roller fun ride to say. I appreciate any info good or bad and suggestions and changes or modifications as needed thanks.

Phil,

 

sounds like a fun ride, without knowing an specifics on your motor with 16 lbs of boost I'm gonna say youll be pushing that pump to its max. Placement is very important to control boost on your gates, so spend some time and reseach the best way to mount them so you can avoid the issues that pop up when you don't have good enough flow into your gates.

 

Cool build.

Your NA motor is going to nearly max the pump, then your going to more than double it? I don't think the Fitech is going to be enough either. Those heads flow 328 cfm @ .600 lift, in a boat application you where everything is optimized for the peak power range it will be no problem to make 650+ w/out boost. You should be looking at HP in the 1350 range at 16 psi.

 

I agree with previous comments. Any turbo on a BBC and you’re looking at 4 digit horsepower running double digit boost numbers. You may be limited by the fueling capabilities of the pump and the fitech unit and not the turbos. Agree with wastegate placement and routing, to limit your engine those are going to have to do their part. Not sure on 2 44mm and a big block, but most run those on a small block application and they work very well. If there’s any change the big block could overpower them placement once again is key to not letting that happen.

 

Thanks for the info. I'm assuming the pump referenced is the Berkley pump. The pump is built by ARS performance pumps has stainless impeller and inductor plus a top loader, new HP intake and adjustable shoe. As for the boost 16 is max anticipated but I don't really like to high string anything so may run around 10 to 11 reliability is important. The motor is well built Cali's steel crank four bolt studded H beam rod's Diamond pistons the list could go on. I usually don't cheep out on the heart of the project. I've used this builder way back in the day and over the years and is well proven on his methods and reliable as knowledgeable. Been doing research for almost a year now on wastegate location and best practice's so got a good ideal on that. Is the 44mm a good size on the wastegate for the application? one on each side of course, is the 50mm BOV sized good and running two of them is ok correct? one on each side As for the FI-tech its support up to 1,200 HP 8 injectors and will allow up to 25 pounds boost. I'm thinking that should be enough and even if I approach that I'll dial it down to maintain good precative of limits. Fueling on the Fi-tech is dual stage system I'll run high flow Holly secondary electric fuel system that supplies a constant supply at 13 GPM to the G-surge unit that supplies the FI-tech with a dedicated PSIG of 65 and a stand by supply of internal fuel for 3 minuets if the secondary looses supply with fuel at mid tanks or lower. I've planned for lot's of mishaps and monitoring of all vital items needed. At some point I'll be posting photos of motor and looking to feed back on my set up. Allot of this is in the building stage and plenty of support from work. As for me I'm an instrumentation tech at Pfizer pharmaceuticals but do allot of machining as I have most of the equipment needed but have people at Work that will assist if I cant do any of it FYi.

 

Im in a similiar situation, 547ci, twin rajays with a 2 inlet water intercooled hat. I have 44wg as well, have not run it yet.

Did you get yours running yet? Did you notice the bypass holes inside the Turbine scrolls, you wont need wastegates without blocking those. What boost have you obtained? How did you mount the waste gates through the water jacketed elbows or is your engine not in a doghouse where everything exhaust is water jacketed?

I ended up making a SS spacer with a Y for the wastegate to be placed between the exhaust log and the elbow.

 

I would think that 7 lbs of boost and you will be past the 1k hp mark.
I would step up to twin 50mm wastegates also, you are going to need to control the boost down low so you are going to need good gates for sure.