Here's a wacky question. Has anyone attempted to compound turbo charge an A series engine? i.e. where you use two turbo chargers in series to achieve much higher boost pressures. If each turbo uses a pressure ratio or 2 then you et something like 45psi boost but the wide map of each turbo at a PR of 2. I read about this ages ago and wondered if anyone's tried it.

The downside is these systems tend to be a bit laggy having to spin up one turbo and then the next but some serious power could be extracted assuming the internals hold up. The upside is large boost and the opportunity to intercool twice and increase compression efficiency.

Not sure if it's practical or not but it would be pretty cool to see a 400HP A series!

It will be fun to see your responses!

dont think it as been done to an a-series as far as I know.

The FD series RX7 used something like what you are talking about. Its a pretty complex setup
rx7 wiki

Not totally sure but I think that was a sequential setup. I read about turbo compounding in book on turbocharging, I think it's been applied on larger diesel engines from memory. It would be a cool project.

twin turbo wiki

this wiki refers to it as staged turbos. is this what you mean?

In automobiles, it is used to extend/smooth the power band. Porsche 959 supercar was the first street car to do this.

In older designs (airplanes, diesels, etc.) it was used to get more boost as the available turbos were plenty limited. Today there are many turbo choices, so if you want high boost, you can just use a single turbo.

ddgonzal is on the money for what I mean.

Dont those crazy Yank tractors use something like that?

http://www.youtube.com/watch?v=yQGJW0Iy37Q

how about super turbo
suparcharge for the torque and then turbo charge for anything above 4000rpms

A guy in Sweden mad a Opel Manta with both supercharger and turbo a few years ago, he used a Volvo engine like everybody else in Sweden.... they´ll put Volvo engines in anything.
An A-series with this setup would be awesome...

http://www.youtube.com/watch?v=uqg4SVFYRVI

http://www.youtube.com/watch?v=ZPDBPXEhd_0