I'm just curious to how the plumbing is for the coldside of the turbo when in drawthrough form.. i know for blow-through it's be a charge pipe that connects to the bonnet that feed into the carb/intake trying to get my unc to turbo charge his chevy 250 camaro drawthrough seems easier then blowthrough since the displacement is small
Draw through you would need a flange of some sort to mount the carb to, and connect that to the inlet of the turbo. Pros are no need for boost referenced pressure regulator, bonnet, or special carb. The bad part is that you have eveything between the turbo and the intake full of hot,pressurized, atomized fuel. This mix could squeeze past thecompressor seals and wreck the turbo bearings. Also, if a bad intake backfire ever occured, all that piping goes POW! My guess would be that part throttle would be a nightmare to tune also.
My dad has two draw-through turbo set-ups for small block chevy's. They are very simple to run, but a pain to tune. The most successful kit was on a 73 vette, with a 327. Made a ton of horsepower and torque was thru the roof. It used old Rotomaster, bronze bushing type turbo's. The setup used 1 factory manifold on the driverside, crossed over under the oilpan, and connected to the turbo manifold on the passenger side. the turbo sat about level with the carburetor flange, with the intake facing the intake manifold, where it connected to a carburetor base-plate that was about 3inches thick with a hole in the side for unpressurized air, and a hole in the rear for boost going under the carb to the cylinder heads. The rear of the base plate had a cast aluminum tube that curved around to the back of the turbo for the pressurized air. Kinda hard to explain, but hopefully you can make it make sense to yourself the way I explained it. I will have to get a picture of the setup on a small block chevy so you can see it for yourself. Hope I helped out at least a little....Billy