turbos & PCV

[kmenard]

I figure PCV valves in a turbo motor are a no no...what do you guys do for blow bye and venting?

[LandSpeedRacer]

It really depends on how the turbos are plumbed in relation to where the throttle plates of the carb(s) or injectors are.
I chose not to plumb posetive crank case ventilation by using the intake manifold vacuum, and instead, am using a bilge blower turned around backwards to suck the crank case pressure out:idea: . I'm very happy with the results. Moroso sells a pump that basically does the same thing, mine cost less than $50 for everything, including the 12-pack of Corona's consumed during and after the install .
LSR

[HONDOG]

LSR have you put a vacuum gage on it? This sounds like a very good low buck deal to me.

[texas-19]

It really depends on how the turbos are plumbed in relation to where the throttle plates of the carb(s) or injectors are.
I chose not to plumb posetive crank case ventilation by using the intake manifold vacuum, and instead, am using a bilge blower turned around backwards to suck the crank case pressure out:idea: . I'm very happy with the results. Moroso sells a pump that basically does the same thing, mine cost less than $50 for everything, including the 12-pack of Corona's consumed during and after the install .
LSR
How do you have the discharge side hooked up?

[LandSpeedRacer]

I was suprised how well this works - the bilge blower really cranks. Good idea, I think I will stick a vacuum gauge on the crank case just to see how much I am pulling.
I actually did this becuase I noticed the internal pressure was causing my oil filler AN fitting to leak. Probably the best way is to take your breather set up and a bilge blower, along with dimensions to the hardware store. It was really not that hard.
I had it plumbed this way before:
Sprint Car valve covers with a crossover pipe that ties the two together and has two outlets. I ran the clear plastic tube from the crossover to my crankcase vent reservoir that was mounted on my chute mount. I used the clear tube so I could see condensation (head gaskets) which worked well, but was not a means for pumping the pressure out.
I priced the belt driven Moroso pump and said F-that!, I'll make my own.
I replaced the crank case reservoir with a bilge blower I bought off ebay for $10. Bilge blowers are spark free, so no risk of fire in the event of a crank case full of gas. I mounted it backwards, used a 3" x 2.5" sewer pipe rubber bell reducer clamped to the suction end of the bilge blower, the other end into a 1 1/2" FPT pvc coupling. Then used a 1 1/2" threaded pvc tee, two elbows and two MPT x slip couplings which gave me the right OD for the hose to the valve cover crossover. I replaced the clear hose with . . . . blue / black swimming pool filter hose . . . . also I made it have a riser in it higher than the blower and valve covers so any vapor condensation will drain back to the engine. I wired the blower into my intercooler fan circuit, and presto. Oh, I made a cone by forming SST screen over a trailer hitch ball and trimed it to fit the 3" OD outlet of the bilge blower, so no dumb azz sticks a finger in the fan. Looks pretty cool too.
I have not tried to measure vacuum, believe me, it works. The problem with blown motors, whether turbos or whatever is, manifold vacuum at idle turns into manifold pressure at higher RPM. The blow-bye causes crank case pressure, which means the pistons on the downstroke have to fight the crank case pressure, robbing power. Put the crank case under vacuum and not only do you remove the pressure, you help the piston come down by the pressure differential. The result: More horespower . And in this case . . . for less than $50. I suppose you could buy fancy polished intercooler aluminum tube with 4-ply couplers and t-bolt clamps, but I am proud of coming up with something that works so good for so cheap. Besides, you otta see the looks I get when people see the toilet and kitchen sink parts on my flattie!
Hope I helped and good luck.
LSR

[kmenard]

I would love to see some pics.

[LandSpeedRacer]

I dont have any good shots of the set up but if you go to I think page 7 of v-drive threads, there is a thread called "Shiver Shot" by Sanger Rich. He took some good shots of the back of my boat.
LSR

[HONDOG]

Reason I asked about the vacuum gauge is I have been told by some who run a pump that too much vacuum (10" or more?) will dry up things like wrist pins and cyl walls that rely on splash oiling. This could be expensive!
Don't claim to know myself, fishing for info.
Bob

[Warp Factor]

The blow-bye causes crank case pressure, which means the pistons on the downstroke have to fight the crank case pressure, robbing power. Put the crank case under vacuum and not only do you remove the pressure, you help the piston come down by the pressure differential. The result: More horespower
But......but any pressure the piston is working against on the downstroke would be recovered as the pressure helps push the piston back up........:idea:

[LandSpeedRacer]

On which stroke - compression or exhaust?