Lokiel

Years ago when I first bought my MSM, I replaced the token OEM intercooler with a real one from eBay.

I was concerned with how much the eBay intercooler blocked airflow to the A/C heat exchanger and radiator so I bought the Begi Air Scoop and installed it:




The scoop hangs dangerously low for DD and many people pointed out that while it would help with cooling the A/C heat exchanger and radiator with the extra air, it would also make the intercooler less efficient because there was now additional positive pressure behind the intercooler because of the extra air.

- so out it came!

Years later I installed a 300HP Fab9 Intercooler, TSE radiator, radiator top-sealing panel and SPAL fan and started to think about ducting so I bought matrussell122's Radiator Support Bar in preparation for it.

Here's the front view of my MSM with the Fab9 intercooler installed.
Note how the intercooler dominates the intake and there are large gaps on the left and right hand side.


From underneath the car, you can see massive gaps between the intercooler and TSE radiator and between the OEM intercooler mounting bar and the bumper:


I began thinking about those gaps and thought "Why not create a chamber between the intercooler and A/C heat exchanger and exit the intercooler air under the radiator?".

The advantages of doing this are:

1. There is no pressure behind the intercooler so air can pass easier through the intercooler, making it more efficient

2. Only fresh air will flow into the chamber between the intercooler and A/C heat exchanger (this is air that flows over the intercooler) so will not be pre-heated by the intercooler

3. Air passing through the radiator will only need to pass through the A/C heat exchanger

The OEM front engine bay brace had to go which was accounted for with my Ryobi grinder (with cutting wheel) and Ryobi reciprocating saw (only the 2nd time I've actually used it):




I started with the two side panels and dividing panel whose top edge leans against the intercooler and the bottom is mounted to the MSM's OEM intercooler mounting bar:










The panels are 2.5mm aluminium and the aluminium brackets on the bottom are made from pre-formed 3mm aluminium L-bar.
When I'm happy with it, I'll use nyloc nuts everywhere.

I added a couple of "Elephant Ears" to block off the gaps on the left and right side of the intercooler:


These panels are only 1mm thick and I used the same pre-formed 3mm aluminium L-bar to make brackets for the lower outer mounts so that they don't flex much.

Here's how it looks with the front bumper fitted (not as bad as I feared so I doubt I'll paint or add black vinyl cladding to the panels):


There's a gap below the intercooler and bumper's bottom which I'll need to fill with foam but apart from that, all incoming air should be funnelled through the intercooler or A/C heat exchanger+radiator.

So is this a reasonable ducting solution or have I over-thought it?

andym

I like this a lot.

DNMakinson

iTrader: (3)

Well, what do your temps tell you?

Also, I understand your goals except the elephant ears. Why does it matter where the A/C and radiator get their air that does not go through the FMIC? I.E. does it matter if the air goes over the top vs around the sides?

Lokiel

The car's still in pieces at the moment so I can't drive it yet.

The two side panels sit flush against the radiator with the rubber edge between them.
If you look at the front view of my MSM with the Fab9 intercooler installed (3rd photo), you will note that the bumper's mouth is much wider than the radiator.
This means that when the vehicle is moving, air on those edges will find an easier path either side of the A/C heat exchanger chamber since the chamber gets pressurised at speed (probably only 20% escapes but I want all the air cooling I can get since Queensland is Florida-hot in summer).
I could probably trim the inner- upper lips of the "Elephant Ears" to force the air upwards and into the A/C radiator chamber but at 40mm wide, they help add rigidity to them - if I remake them out of thicker aluminium I'll do that.

My DIY tuning fan cooling solution proved that there's a decent amount of air flowing through the intercooler and radiator and very little either side of the two chambers I created so the "Elephant Ears" do work (FYI: These photos were actually from an earlier time when I was tuning during summer, which is why the number plate is mounted - still need to figure out how to mount it):

DNMakinson

iTrader: (3)

Got you. Thanks. I accomplished that with forward facing panels, creating a box. Now I understand.

HarryB

Offset plate mount; the kind that mounts on the baby teeth. Else, OEM mount that places it right above the bumper opening?

Lokiel

I really hate side-mounted number plates, to me they make the car look crooked so the only place to mount a centred number plate was to the new bar.

I didn't want to drill holes through the OEM bumper and noted that the rear of the new bar cleared the mounted OEM bumper so I could mount my existing aftermarket MX5-Plus number plate mount there somehow.


The green tape on the number plate was used as a reference point, the right edge being the centre of the plate.

I made a couple of 40mm x 3mm aluminium L-brackets to mount to the existing number plate bracket and a couple of double-width galvanised brakets to wrap around the bar and mount the L-brackets to:







I wrapped the bar with a couple of layers of black tape where the galvanised brackets attach to to give them some grip on the bar. With the aluminium rear brackets pop-riveted to them, they don't move/slide at all.

I spent a LOT of time measuring everything up, installing/removing the front bumper multiple times, only to find that it's slightly crooked. Luckily it's only by a few mm so can be easily fixed (hopefully just by bending the original bracket a bit):





I'm currently giving the bar a couple of resprays (painting the front of the galvanised brackets in the process) and will trim off the un-needed end sections of the original bracket.