a turbo works by the exsaust... there is a compressor side, and a exsaust side. The compressor side has a inlet, and a outlet. The inlet is were the air comes from, then passes threw the compressor wheel, and becomes comressed, sending it out the outlet port of the compressor side. the exsaust side has a wheel with fins on it similar to the compressor side... the more rpms you pull, the faster the turbo spins, creating boost. the exsaust side also has a thing called a wastegate on it. The wastegate is what limits the amount of boost a turbo puts out. when it gets to its "set" boost, the wastegate arm moves opening a flap, releasing pressure out into the exsaust. you should goto www.hybridz.org they are dedicated to heavily modding your z.
here is my turbo 76z
https://www.zdriver.com/gallery/show...er=458&thumb=1

 

It is possible to use the Webers with a turbo, but it is probably not the best way to go. Carbs are not set up to put out increasingly high volumes of fuel under boost. They work mainly on vaccume and airflow. I'm not sure how well they respond in a compressed intake.

You would also need an intake tube with a long tunnel that connects to all six of your barrels and seals good.

I would suggest looking into some more internal engine modifications to work with your webers and keep the engine n/a. If you go to turbo, just use a fuel injected setup.

 

http://auto.howstuffworks.com/turbo.htm

 

Jim Cook still has a Cartech setup with Webers for sale in their online cataloge. I'm not sure how up to date it is. I've often wondered how well this setup worked too.

 

I've seen the old 4-cyl L-series like an L18 with a small turbo running through a single SU carb. They claim gains of 20hp and 30lbs of torque!

Again, you can keep increasing the boost and pump more air in there, but I don' t see how the carbs will know when to put out more fuel. They certainly should be capable of huge amounts of fuel, its just a matter of them getting the right mixture output at the right rpm/boost levels. That's what computers and fuel injectors are for! hehe...

So with that Weber setup you may be limited to 180-190hp max. The intercooler is probably not nessisary unless there's soemthing I dont' know about those carbs.

 

I agree FI is the way to go, and the carbs are a big mystery. They claim 300hp in the catalogue. I read somewhere hot air through the carbs really makes them act wierd, so an intercooler would almost be a neccesity. If someone really wanted to stick with carburetion for some reason, I would think having the carb on the intake side, like their Holley 4 bbl setup would be best. There was a green Z featured in a previous issue of Zsport that had this setup. I guess its not offered by Cartech anymore.

 

Turbos can be done with carbs... check out Corky Bell's book Maximum boost (its the turbo bible - read it cover to cover and then read it again).

That said, increasing fuel with boost is largely a matter of the emulsion tubes. Coventional emulsion tubes bleed air against the flow of the fuel, essentially acting as a brake so that the fuel slows down and moves more like air, AFAIK turbo emusion tubes cause air to boost the speed of the fuel by moving the same direction as the fuel thus, the higher the boost of the turbo, the higher the speed of the air, the higer the fuel flow (you have to make up for this with increased fuel flow into the bowls as well so they don't go dry under longer periods of boost so you you need an fpr that will handle this as well).

All of this is assuming a blowthrough turbo, there is of course the suck through version where the carb goes before the turbo, no special emulsion tubes are needed, but the air fuel mixture goes through the turbo, kinda frightening, if you ask me.

-Lukas K.