Why cant to PI & TMIC?

I have thoughts that live rent free in my brain and idle mind times lead to crazy thoughts. I will preface with how this fits within my goals and would like to figure this out or put a nail in the coffin...

I am building my car to remain closest to the original package Mazda created and not in search of max power or building for the track. A Mazdaspeed6 with the more power like I think Mazda would have built it is the goal. I would like to have it look sleeper/stock as possible. To do this I use black options, not flashy colours/chome, I keep plastic panels and shields in place as much as possible.
A CST4 is the next item I need to purchase to be able to make it to 400hp using WMI. However the idea of purchasing a CST5 so that I can build a bottom end and add PI later to reach the ultimate of 500hp is real hard to forget. If I could make this work, I will be able to still check a few boxes...

1. Ditching WMI...its not its all cracked up to be.
2. Keeping stock flange turbo
3. Keeping TMIC and shroud
4. Keeping EGR and stock manifold junk
5. Keeping the backside of the valves clean

This is an armchair conversation and Im just fact searching and spitballing. I cant say that Im hard up to make one off parts and engineer some holy grail. But if you are interested in a chat about it...

What is the consensus on why PI cant be run with a TMIC?

My initial thoughts were related to the space available under the top mount. So I measured the space between my OEM TMIC and the top of the OEM manifold where it meets the head...78/82mm on each side. With injectors as short as 34mm, there is 44mm of room to fit a fuel rail and have some air space. Still maybe too tight. I came across this photo in Corksports 8th port kit (here)...

However, In the description Corksport also states FMIC only. If you subscribe to conspiracy theories, continue reading, lol.
***I just re-read thru the CS page and I dont see anything about the 8th port kit not working with TMIC***

Initially the only way to add port injectors was to use a spacer plate. This would change the distance of the intake manifold from the head and therefore change the location of the front mounting points for a TMIC. 2 options only remain to keep the TMIC mounting points in the OEM location. Machine injector port provisions into the stock manifold or use Corksports intake with port option. Im guessing the OEM manifold might need to be single runner modified to make it work. I suppose the amount of heat around the injectors and rail could be a issue. Not sure how to deal with that or if its even a problem. Could be costly too if that lead to a leak of fuel .

Another idea I had involved these ports on the CS manifold where the large chamber meets the runners...

Fuel could be injected here. Im no automotive engineer, is that going to cause problems?

Im also curious about the underside of the OEM manifold, if there would be room to slide a rail in there somehow...seem like a hail mary throw at an already crazy idea tho.

Based on Corksports FPR pic, Id like to see what I could dig up to make that work. Initially, the symposer(?) would need to be relocated, but thats easy enough. Anyone have any interesting thoughts or areas I need to consider?

 

That was Will Dawson's (PD Tuning) newer ms6 build in Corksports picture with the fpr with the tmic. He had the PI Mocked up but not utilized as he was trying to push a k04 to the max before upgrading the turbo. He dropped a valve a couple years ago and the car has sat since. But it may work

 

Thats good to know. Thank you Sho! I have decided to go with Will for tuning already when I upgrade turbos. 2 birds...

 

if you get anywhere with this let me know. Ive been looking into something similar or a different variation of a 6th port.
I ran into someone that basically had the the 6th port welded onto a cold pipe for the 6
I want to try something similar but use weld in bungs and direct lines instead of a fuel rail.
Though if you end up spacing it right and can do tmic + 8th port it would be better over all

 

I don't think using those ports for fuel injection would be beneficial. You want the injectors to spray as close to the port as possible. Having them down there could cause puddling if the air charge velocity isn't strong enough.

If you're shooting for 500 wheel horsepower why not just go FMIC painted black to hide it? You won't sacrifice that much spool time/response by doing that change. Plus you will have cooler BAT/MAT overall. There is also the bonus of lower under hood temps as well as ease to work on things.

 

Everyone always forgets that in order to get a fmic that is better than an upgraded tmic you have to cut the crash bar

 

"better" is subjective. FMIC doesnt have the heatsoak issues that TMIC has.

 

lower capacity to shed heat is a worse intercooler. heatsoak is not an issue on the street, bats come down as soon as you are moving. unless you are going to a bigger intercooler core fmic is worse.

thats not even considering the low quality fmic kits people buy. if you are getting a whole fmic core and piping cheaper than a tmic it is not going to work better.

 

I ran the CX Racing core which was garbage but the piping kit wasn't so bad. Once I swapped to a Treadstone TR8 core it made a massive improvement.

I also didn't have to cut the crash bar to do it. But mine was Gen 1. Even if you have to cut the crash bar a bit to fit you can weld in metal to the bar to reinforce it again. Just extra steps that's all.

TMIC isn't bad but if clearance for PI or other things is an issue what other choice do you have?

 

i think that is what OP is trying to figure out in this thread

 

This idea got put on the back burner for a while. Even the car hasnt moved, just no time.
But yes, in the end I would like to have a PI setup with top mount so the car remains very stock looking but isnt.
If it is not possible, I will prolly remain 400hp on WMI.

 

Was looking at CS pic of the PI rail

I think the only issue might be clearance towards the front of a tmic, I think I saw a pic online where someone just shimmed the front standoff to raise the tmic up in order to clear it. You'd certainly want the stubby injectors. Rail may add some resisting to flow through the intercooler.

I'm in the if you want it, try it mindset.

 

Just my two cents, Derrick doesn't do anything for no reason. Everything he and the entire life span of Corksport and every team member to come and go since the dawn of CS, has made sure everything is perfect. Having said that, I feel like Derrick would have made a point to be able to keep a TMIC and add port injection. If that wasn't the case, why did he allow the addition of the TMIC mounts on the manifold? I mean... you could always ask @CorkSport - Derrick or @Barett@CorkSport

It most definately is not outside of the relm of possibility. I would almost gamble that CS had their very own TMIC in mind when designing the intake manifold and running port injection.

Just my two cents though... and I don't really know anything...

 

@Enki answered the question <<HERE>>.

 

I would just give Corksport a call. I'm sure they have done some R&D and can tell you if PI is possible with a TMIC. It's highly likely that they've got the information.

 

they did, people are trying to make it work, corksport on their intake manifold product page says "Top Mount Intercooler (TMIC) Mounts (hardware not included & TMIC cannot be used with port injection)".

Edit: I see what you're getting, at they may know what shimming etc is needed

 

What I have concluded is the corksport intake has added material above the intake/head face to facilitate machining for the PI injector bosses. Damonds adapter plate has the same. Unfortunately the added material plus the 34mm of the shortest injector isnt small enough to allow the use of TMIC unless the TMIC is raised. At that point you run into issues with the hood and viable airflow to the TMIC (especially the Speed6, which is already at a disadvantage).
Perhaps when I get there, I can look for more solutions. I had even looked into side feed injectors (SR20s, 1JZs, RB25s) to see if they would net more clearance. But right now Im thinking a custom machined fuel rail could save some space. But like I said when I get there. I dont know if the OEM intake has enough material to be machining injector bosses either.