AE92 intercooler upgrade... Random thoughts

[BLSTIC]

Ok so my AE92 Levin GT-Z is nearly on the road. And I've determined that I'll have to do something about intake temps. Based on the following:

Top mounts aren't efficient in stop/start traffic
98 octane fuel is as good as it gets in cairns
I have a 185mm crank pulley
I have an exposed (but beautifully made) HKS pod filter
It's really, really hot up here

So I'll be toying with the intake setup quite a bit.

First up (once my intake temp gauge arrives) I'll be closely monitoring the intake temps on a daily basis, and once my differential pressure gauge (for measuring airflow through the intercooler) arrives I'll get some data on that too.

The first modification is likely to be a new undertray to better extract air from the engine bay
Next will be a decent water spray
Then I'll do something about the exposed pod filter, depending on the air temperature inside the pod (likely to be high)

After that, I'm stuck. Apparently putting a front mount on these cars affects throttle response negatively, and there definitely isn't enough room to run a fan (unless I modify the scoop to be laughably large). The ultimate idea is to run a water to air intercooler but I haven't found a single photo of a 4A-GZE with one...

Yes I'll be posting the data when I do this

Thoughts?
Ben

[TERRA Operative]

Here's my recommendations from my experience with my old AE101 GTZ Levin.


Intercooler water sprayers make a huge difference, install them. I used to drop my intake temps from ovar 70 degrees to nearly ambient (25 - 30) with the water sprayer. Makes a big difference to the power and response. Go to Autobarn and buy the 'misting' sprayers. Here's my setup I had:





Definitely make a box for the pod filter. A mate and I tested the open and enclosed pod filter thing on his Mazda 323. With a bare pod, we got intake temps of 80 degrees as it was sucking the hot air straight from the radiator. With it enclosed with a cold air induction, it was almost ambient.

My setup:
(There is also a duct from under the filter, through the stock 2.5" hole that is there, down to the front bar for cold air)





Don't bother with a fan, it's too hard, too noisy and will be a restriction at high speeds. Forget a front mount too, it kills the awesome throttle response that makes these cars so fun to drive.
Air to water isn't *too* hard, as long as you're handy with the pipework and electrical side of things, or can pay someone to do it. You could mount it in the stock location, or over the top of the gearbox if you can't fit it on top of the engine.

I would leave the undertray to last, there's a bit of aerodynamics to be taken into consideration with that, as it will affect airflow through the radiator, intercooler as well as possibly the handling of the car at speed as well.
Oh, also make sure the rear of the bonnet near the windscreen is properly sealed up (there should be a rubber strip along there). If air can get in, being a high pressure zone, you'll end up with air pushing in there instead of through the scoop which is in a lower pressure area.

[BLSTIC]

I'll be measuring flow through the intercooler when I do the undertray, don't worry about that...

[TERRA Operative]

Don't forget to measure flow through the radiator, and downforce too to make sure you don't get lift.

[BLSTIC]

Downforce is much harder to measure, but if i'm decreasing pressure under the bonnet...

[TERRA Operative]

Potentiometers on the suspension to measure average travel, or even load cells on the under tray to measure the down force on that part itself would probably work ok. I doubt an under tray will hurt, but I've seen things go either way depending on surrounding aero mods and the base aerodynamics of the particular car. Would be a fun project to build and test. The plastic sheeting that's used for signs that's like corrugated cardboard is good stuff to play with for prototyping. Light, cheap and easy to work.

I have a brand new ARC down force meter here that no-one seems to want to buy, I should crack it out to do some measurements of my own.....





Oh, with that big crank pulley, be sure to keep the oil topped up in the supercharger. You'll be pushing the supercharger beyond its max limits when you hit redline...

[BLSTIC]

Hmm that's a thought, hadn't actually checked the oil level in the blower... It's a Toyota specific oil, no? I heard it's pretty pricey

As for the aerodynamics...

I'll be installing a tray that runs from the front of the lower edge of the bumper to (at least) the front jacking point on the crossmember, and the side cover plates that SHOULD be there but aren't (the one that covers the crank pulley from the wheel arch area, and the matching plate on the other side below the battery).

Pressure measurements will be made across the radiator and intercooler before the new goodies, and after I will also be measuring below the new tray. That will give me a guide to the forces acting on the bonnet and the new tray, as well as the airflow through both cores.

I like your intake setup and sprayers, however I'll be doing things slightly differently (I still have a battery where your pod is unfortunately, plus some pesky, hard to package, air-flow meter from the 80's...). What are the legalities of the battery move?

How does that downforce meter work?

[Duk]

Rather than fart arse around with suspension sensors, check out Autospeed's article on the effectiveness of bonnet scoops http://autospeed.com/cms/title_Under...9/article.html and http://autospeed.com/cms/title_Under...0/article.html.

While you at it, check out the articles on intercooler water sprays. They've got quite a few articles on them, but http://autospeed.com/cms/title_World...0/article.html and http://autospeed.com/cms/title_World...9/article.html are excellent articles on the pure effectiveness of evaporating finely atomized water (I've got the same pump and nozzle in these articles and they can make a huge difference to the cooling capacity of the outside unit of a split system air conditioner).

[BLSTIC]

Ha, autospeed is where I got most of my ideas

Once I get the car on the road I'll be buying one of those magnehelic pressure gauges so I can have some SCIENCE! behind me

[mattysshop]

i would definitly be looking for a different core to use though... the toyota cores flow very average compared to even ebay spec bar and plate..

i had a front mount on my AE86 GZE setup... with decent thought out piping, and a nice fabricated smallish cooler it was very responsive

AE86 4AGZE incar test
www.youtube.com/watch?v=4uS3uyRiIgI

[BLSTIC]

Hey TERRA, what pump are you using for those sprayers? And does the spray get any finer with higher pressures?

Incidentally I checked the oil level in the blower and it's at 3/4. But it's quite sticky and smells weird. Does the Holden blower oil match this or has someone put a random oil in my baby? It's a golden colour and I know the Toyota oil is supposed to be clear.

[TERRA Operative]

ARC made an intercooler, they pop up on various forums, ebay and Yahoo Japan from time to time.


For my sprayers, I used the pump that went to the rear window and just rerouted it, that way it was all stealth like the NOS in Dominic Torettos RX8.
Otherwise, you could just add another pump taken from a wrecker.

The oil should be clear or slightly golden and as thin as transmission fluid. I'd say someone has used engine oil instead.....
Drain it out (There should be a drain plug IIRC, or you'll have to open the sump housing) and flush it out with something like wax and grease remover or similar. Then refill with the right stuff.

[BLSTIC]

I just bought an intake temp display off ebay. I'm $15 poorer and should arrive in two weeks

[TRP]

Ive got a Trueno GT Z & Ive just rebuilt it. Im stuck looking for a water to air unit as well. Ive got a Subaru unit & a really nice little heat exchanger & Ive relocated the battery to the boot but Im struggling for room to fit it. Really interested in what your sciencey stuff results were too.

[TRP]

I like the look of your cold air box. Im gonna give that a crack. TERRA your a legend buddy