This is a project that I might be doing soon and curious if anyone else has attempted this.

I plan on chopping a lower turbo manifold and trying to mate the upper flange from an N/A to it.

Any insight would be great

 

I thought the turbo lower manifold wasn't a very good design since it was designed primarily around fitting a turbo next to the engine and not for the best airflow? Especially when used in a N/A format, which if i remember correctly your car still is? I think peejay has posted about this before but i could be mistaken. What were your goals of doing this modification?

On another note, i have been curious about how an s4 N/A manifold would work on a 4 port engine if the manifold properly turned into a 4 port manifold. It could be a good combination

 

This isn't for my car actually, its for a customers of mine actually. He currently has a 6 port S4 and wants to turn it into a 4 port engine while keeping it NA still. James from rotary dynamics will be doing the actual engine build and I'll be doing everything around it. I need a 4 port lower to atleast get the intake to go on there properly. But I wanted to keep the longer intake length from the NA though. Would I be better off making my own tubular lower?

 

the turbo intake makes a really tight bend coming out of the engine, to make more room for turbos, which makes it so/so for NA's.

the NA manifold is straighter and uses larger diameter bends, so it actually flows better.

the NA and turbo have the same intake bolt pattern, and the primaries are the same, its just a matter of hogging out the 6pi stuff and filling in the rest.

tubular would be fine, but i think it would be more work?

 

So you're suggesting keeping the NA lower intake and just jb weld fill in the 6th port and just port match accordingly?

 

yep. for me that's the easiest/best way. for you maybe tubular is less work?

 

I'll have to wait until I get all the parts in my hands and will decide then what would be easiest ... or more interesting way to do it It would all be in the name of science right!

 

Not really related to this thread but still intake, a customer came in today in hopes of having some modifications done to his intake manifold for his AE86. He did an engine swap and had to relocate the throttle body from one side to the other. Here's a couple of pictures from that:

 

I have an s4 NA rx7 and want to put back on the stock manifold but will it fit. the reason i ask is because the lower intake looks strange. has no actuators. Could this be a 4 port intake. manifolds looks like its off mk1 rx7 turbo. any ideas whats going on here. will the stock exhuast clear lower intake?