I tried searching for info on this and from what I've found it looks like the timing on the center exaust port is the same as the side ports. If this is so, I've been thinking about a custom turbo setup (I like building stuff myself) and was wondering if this idea for my turbo manifold would work.

Would it be possible to use the center exhaust port and have that go directly to an external wastegate for boost pressure control? I'd then have the front and rear exhaust ports maintained seperate for a twin scroll turbo. Haven't decided on a turbo yet but I can get used ones off a MR-2 or Evo for cheap (both are factory twin entry turbos). This setup would make for an interesting layout..Thoughts?

 

WHOA!! if you do this, you gotta let me watch/fetch tools etc... been quite a while since i worked in the garage, but i would love to be around for this..

 

well the pressure you are trying to control is what is traveling through the turbo pipes... if you seperate out the wastegate then you are not controling the pressure within the trubo pipes.... now technically you could run a twin turb set up with the front and rear on one turbo and the middle on the other but i dont think you need and it is way labor intensive and a lot of things would have to be relocated... this is just my opinion so it vertually means nothing

 

Technically it would work. To a point. A big problem you'll run into is that if you have a siamesed center exhaust port that only goes to a wastegate, when that wastegate is closed and those ports can flow to nowhere, they can only flow to each other. One will always be at higher pressure than the other. This would not be good news and they WILL cross flow.

There are other reasons why this wouldn't be good but that should be reason enough.

 

Thanks for the reply. Its kinda what I thought, on paper it would look like it could work however the flow dynamics could create a cross flow between the rotors 99+% of the time (i.e. wastegate closed).

Okay, back to the drawing board .

Hey Paul,
I'm just tossing around ideas in my head. I've messed with turbo setups on my previous cars (MR-2s - i've owned 2 of these, WRX and Porsche 944T) all of them turbocharged from the factory. This is my first N/A car. Right now I'm just picking up neccessities for a possible FI future. Wideband O2, assortment of gauges. I'm still hoping that (along with everyone else) the SC kits work out well as I might just get one of those.

 

The sum of the ports is barely enough to empty the motor as it is.
Eliminate the center port from the sum and you will have nothing be high EGTs and very little flow to the compressor.

 

Thanks MM.
I don't know what I enjoy more, the technical knowledge of your posts or your avatars

 

Pffft...the avatars...of course

 

nah... the tech posts.

 

kinda like tastes great, less filling..

i think or win, win.

beers