I've had a look at the Turbo exhaust on the 13B and the overlap is quite a bit more, as the extra area is in hight, compared to that of the NA housing.

The Turbo actually opens at the same time as the NA housing but closes later, as you alluded to.

So the Turbo housing is 'OUT' for the single PP.

( Hope your taking notes here Rusty). 

 

Interesting observation, but are you sure your turbo housing hasn't been ported? 

 

No rusty the Turbo exhaust housing hasn't been touched!

 

 I just set an 87-88 6-port housing on top of an REW housing, and the exhaust ports are identical in side, shape, and location.  The only difference is the 6-port has the splitter.  Take a look at Paul Yaw's article on port timing basics-  http://www.yawpower.com/techindx.html    He gives the timing for intake and exhaust on lots of different housings, and he shows the timing to be the same also.  

 

That's interesting - I will send a photo, so you can see for yourself!

 

For fun, check out the Picture Gallery.  Start at picture number 25, and you'll see his PP modification.   

 

If those reading this are confused or not considering PP take no notice - this is mainly for Rusty's information for when he converts to PP. 

 

I still want to do a test one day, with junk housings, but I've got a lot better things to do with my time at the moment.  I did spend a whole morning reading PP posts on the RX-7 Club list the other day, and it just reinforced what I've been told about this being a bad idea.  There were some nice pics of people boring their own ports though.  

 

Don't worry Rusty were here for you when you need help!

George ( down under)