KOU Motorsports FWD Update Options

[JMoushon]

OK, so nearly 4 months have passed since I signed on with KOU Motorsports, and much has changed with the car. Some would assert that with a sponsor and 4 months' time, we should have built a monster, but allow me to lay out our objectives.

When Travis abd I first set out on this adventure, we had a simple goal. Run 12s consistently in a street-driven FWD DSM. Sounds simple, doesn't it? Well, enter the facts and we'll see how things look...

Firstly, I live 100 miles from the shop. With the seemingly omnipresent construction on I-74, this is about a 2 hour trip each way. Next, I work as a tech full-time at Saturn of Peoria. Lets also add that for the last few months, I have been making the trip out to KOU for work. Not on my car, on customer's cars.

So, in the past 4 months, we have had roughly three days time to work on the FWD.

It started as a 14b/smic/450 car. Then it changed. First came the MAF-T, 660s, and Wort E-PROM. Not a bad bit of mods, and driveability with the new ECU was drastically improved. Then we got a wild hair to try out a big turbo. In goes the Frank3. Well, that lasted all of about 12 hours, out it came. A bit too much for the type of driving I like to do. I guess I am spoiled by higher than normal compression and a small turbo, but I despise lag. In retrospect, it wasn't that bad, but the big turbo went against our original goals, so it was retired. Back to the venerable 14b we all know and love. A few more weeks go by, and we decide, on a whim, that maybe a 2g i/c, with it's bigger inlets and outlets, would be good for our relatively mild set-up. It works great, for about 1/4 mile. The flow increase is apparent, but unfortunately so is the lower volume of the unit. Time to put a band-aid on the band-aid. An hour later, we have routed 2 OEM washer nozzles into the bumper, spraying onto the face of the i/c. Note: Although the spray does not doo much during a run, heat soak recovery time dropped from 15+ minutes to about 3 minutes, for what it's worth. I run that for about a week, and Travis and I decide enough is enough... If you're gonna see how quick you can be on a 14b, why not just use the right parts? Enter the Air/Water intercooler. A beautiful piece. Hand fabricated aluminum, 3 gallon sump, the whole shebang. 3" in/out, awesome. With some help from Travis and Wort, it goes in without a hitch. Response has clearly improved, lag is nearly non-existent. Which brings us to the current day... The i/c is great, albeit currently it is functioning more like an interheater, as the pump is not yet functioning. Run an A/W i/c empty, and you may as well not even have an intercooler. I picked up the necessary fittings, hoses, and a switch today, and will have it all plumbed up by the weekend, if all goes well.

We are by no means done, but with all the supporting mods in place, we should be ready to see how far a 14b can be taken. There is still more weight to lose, and we may have some other tricks still up our collective sleeves, but it's very close. In this, we will also see how fast a 14b car can go on the stock clutch. Scary, and I'm certain when I start leaning on it it will go, but it'll be fun to see.

To this day, the set-up is roughly as follows:

14b, ported to within an inch of death
Air to Water intercooler with full 2.5" piping (KOU)
MAF-T with 3" MAF (blow-thru)
KOU chipped EPROM by Eric Wort
Denso 660s
Walbro GSS342 255 hf/hp
Apexi S-AFC2
Kris144 Intake
3" TBE, side-exit
Ported o2 housing
KOU ported 2G manifold (beautiful)
KOU stainless clutch line
KOU shifter bushings
Ball/Spring MBC
Nitto NT555R DR's
Front: KYB GR2/Eibach Pro-kit
Rear: KYB AGX/Intrax
AWD halfshafts

That covers most of the general set-up. There is more, check the garage for everything. It looks to be a promising year, I'm sure we'll get tired of te 14b by mid-year, and who knows what will happen!

[wortdog]

My understanding is that the a2w is able to take a lot more heat out of the intake charge and bring it very close the temperature of the water inside of it whereas the a2w at its best will only be able to bring you to within 20degrees of the IC temperature.

Actually, the water can only take heat out of the intercooler, not directly from the air. You are still limited by the relatively poor heat conductivity between the air and the intercooler.

A good air to air intercooler, like the one on Frank, partially sits at ambient temperature all the time(1/2 to 1/4 of it at least). Part of it is also much warmer than ambient, so you have a gradient of cooling capability as the air flows through it. Its not uncommon to see only a 5-10 degree difference between IC outlet temps and ambient with a really good air to air, due to the large amount of surface area for both cooling interfaces(ambient air <-- intercooler, intercooler <-- charge air).

Most w2a have less internal surface area for the intercooler/charge air interface. I'd guess the a2a core on Frank has at least 6 times the internal area of the a2w core we're talking about. If only a 1/4 of the a2a core is at ambient temp still, that's still 1.5 times greater area than the a2w cooler, plus the other 3/4 of the a2a has already cooled the charge down quite a bit. The a2w can only outperform the a2a if you can get the IC temp well below ambient.