Intercooler AFTER Throttle Body? Intake Tuning
 

https://cimg5.ibsrv.net/gimg/www.rx7...5fde0e368b.jpg

Pro's/Con's? So I'm thinking of trying this I've been searching into this but looking into it more. The is my winter project drift build 2016 season... so you of more knowledge than I, if you have input before I waste countless hours and $$$ that would be awesome.

But, SO why hasn't Mazda or SUBARU for that matter tried this or have they??

WHY?
I want to utilize the factory tii intercooler scoop but make it more efficient. Keep it looking stock(ish) under the hood, clean up the engine bay, and play with some intake tuning on a RX-7 see how it responds. (I like to reinvent the wheel, hopefully learn more as I go about engines and tuning).

My plan;
I have the MS3X, 13B REW TT, TII Trans, Shell, using the factory twins (which I'll cut up and re-locate).

So I want to fabricate a custom intake manifold using 4 independent runners, I'll probably use 8 smaller fuel injectors (4 Primary 4 Secondary for better atomization) which I will weld to a Bell Intercooler Core. After the intercooler I will weld a collector channel to the throttle body attachment which I want to try a Mustang Throttle Body for a couple reasons;
1) IAC and TPS easier to config to the MS
2) Smaller throttle area = more TQ, better response, and hopefully won't have so much low end/ random dying issues.
3) Easier hot-pipe attachment from the turbo.

I plan on fabricating a throttle decay (plunger thingy to slow the throttle plate from closing too fast).

with more volume between the intake port and throttle body should increase low rpm performance, but I don't plan on having a whole lot more volume than the factory REW intake manifold. (you don't need a huge intercooler for low HP numbers).

My goal is a quick spooling low end torque probably 250hp REW-tt Im guessing the high end RPM will suffer maybe a tad (Why would you do that to a rotary? I know!) but I drift and throttle response > High HP numbers.

All the FC's/FD's I've built run a huge Holset turbo Power is awesome! from like 5K up lol id rather spin it slower and have more bottom end torque. Most of our courses locally are sub 100mph any ways.

So... you plan on placing the intercooler core directly over the hot engine on a car that is designed to compete in low-speed events. How do you plan on getting a large volume of ambient air through the core and keeping engine heat away from it?

Given that an intercooler changes the air temperature and pressure, where do you plan on mounting the IAT and MAP sensors so that the EMS can accurately meter fuel?

Rather than using 8 crummy old fuel injectors, why don't you just use 4 modern Injector Dynamics (Bosch EV14) fuel injectors?

Have you considered a horizontal or v-mount intercooler?
http://image.turbomagazine.com/f/105...ntercooler.jpg

60-80mph so slower not stand still.
I've ran v-mount before id like to use the factory T-II hood and keep a factory ish appearance under the hood.

MAP and IAT would be after the intercooler before the 4 individual runners.

I was thinking of running a ducted fan and potentially a water sprayer to help create a low pressure under the intercooler during cool down.

Also with less piping less pressure drop and faster responce.

I'd bet $2 8 "basic" 220cc injectors will atomize fuel better than 4 expensive 550cc but I'll look into it I could be wrong.

You pretty much lost me at the "drifting" thing.
But I thought you wanted to "clean up the engine bay", yet you're going to hybrid some TMIC on a 13bREW in an FC with "cut up" stock twins and a ducted fan and IC spray system. And then REALLY simplify things with 8 small injectors instead of 4 with no mention of how things will be controlled. And all this to keep that "factory ish appearance under the hood".

You lost me again.

Air has mass and moving air has inertia. By moving the throttle body away from the engine intake ports you decrease your throttle response and could induce some odd off-throttle behavior, to include stumbling or tuning issues. Since you further want to delay the TB closing the first point may not be an issue for you but in general it is considered to be a very bad design.

As to keeping the stock IC placement that is a bad idea. You need to keep the incoming air cool or risk lose your engine. The area of the scoop is really small. Furthermore, since you're drifting you further decrease the effective scoop area because it's at an angle relative to the incoming air. The best you could likely do is use a water to air IC somewhere in the intake tract and run a heat exchanger in the stock location. If you're clever you'll have a relatively stock looking appearance from that.

Although, given that you're talking about a custom manifold it seems moot to care about the appearance. If you mean outwards appearance then think of something clever to mask the changes. I recall in the late 90's it was in vogue to spray paint FMICs black for a variety of reasons that all came from the desire to hide its presence.

Injector pintle design has come a long way from the 80s. Newer name brand injectors, even with a higher flow rating will atomize fuel much better than older injectors. Given that good tuners with modern 2k+ cc injectors can achieve smooth idle you have nothing to worry about with 500+ cc injectors. They're not considered large these days at all.