Ok, As I'm sure many people here know, My engine is blown, and getting rebuilt as we speak.
I had a high compression, street ported S5 N/A block that I put a turbo on, and saw 13-14 psi at times (with a stock DP and a ported wastegate! woah!) Anyways, the engine blew 2 apex seals, since the stock TII fuel system wasn't enough (Duhhh) Plus I had a weak seal to begin with.
Anyways, the engine is getting rebuilt with 3mm N/A S4 rotors (lower comp) and mildly ported (mostly polished) turbo 4 port housings. Not to mention the DIY wideband I have, FD fuel pump, and more wastegate porting.
Should be a better mix!

Anyways, since I'm using 4 port housings, I have an issue with the intake manifolds (6 port)
I saw some thread a while ago on this, but couldn't find them.

I *definately* need to keep the VDI upper manifold, so my choice is with using a TII or N/A lower manifold.
Will the VDI upper mani bolt onto the 4 port lower??
I know the N/A lower mani will bolt onto the block, and need porting in order to port match.

The big question:
What's easier to match up, the 6port lower to the 4 port block, or the 4 port lower mani to the 6 port VDI upper? (If they bolt up at all)
Thanks!

 

Well the big difference is the 4port lower manifold is a lot longer than the 6 port so you would be looking at possible clearance problems with the hood. But that is at first glance to your question. Anything can be done it's just a question of money

 

Wow... no other replies???

 

Just curious, why much you keep the VDI manifold?

 

Too much involved with the vacuum system, plus the TPS.. all that.
Plus the NA mani has the intake on the passenger side- much better for my IC setup- I'd have to redo the piping.

 

icic....
Well, I can check for you.
I have a S5 TII complete block and a S5 NA complete block sitting in the garage. I'll let you know what I find.
However, I don't think I can get to it until the weekend.

 

But for the time being, check out
http://www.mazdatrix.com/c-2.htm

You can compare the gasket shapes and see which fits better
Hope that helps

 

I had a post on this thread, it would appear to have been munched. I've got an S5 TII lower intake manifold. Want to see if they match up?

 

if you get the the 4 port housing the only differnce with you motor and a turbo motor will be is the exhuast ports that diffueser, which you can remove, other than that you should be able to use all turbo manifolds, and get rid of that damn rast nest!!!!!!!!!!!!

 

He doesnt want to use all tii manifolds..

 

You won't be able to do it, none of the the 6 port stuff mates with the 4 port stuff.

And why don't you go with 9.0 or even 8.5 rotors instead of screwing around.

Get bigger injectors.