Tom's GTLIMITED

[tomnomnom]

Got the exhaust all wrapped and turbo beanie on

Car can now come off the hoist while I sort out loom, ECU, injectors and other things like coolant hoses, radiator etc..

Still a while yet but I'm happy with the progress I've made in the past few months

Really need to paint the rest of the car too

Turbo beanie and heatwrap

Engine bay side shot

Engine bay above shot

Yes, those are more wheels

AVS 5 16/17 stagger

[tomnomnom]

Has to pull the dash out, the wiring in this car is a bit dodgy. There was an immobilizer installed which is now gone

Pulled a lot out which isn't being used
All speakers and sound system wiring gone

I need to fix the dash board up before I reinstall it

Dash out

I tucked the body loom away under the centre console, mounted fuse box in behind passenger seat, extended and rerouted tail light loom to go through the rear fender.

Hole for tail light loom

Using wire to pull loom through

Oh, I've also realized I haven't mentioned in this thread I did install a KAAZ LSD a couple years ago
Love it, definitely worth the money

[tomnomnom]

Started doing more dumb shit

Always wanted to vent the radiator through the hood.
If you've ever been over 200km/h in your 2, you will know that front end starts floating...
Even the chicane at Taupo track can induce under steer with enough speed
Needed to reduce that lift! Perhaps even create front end downforce
Having proper ducting and flow will also aid in cooling, not that mr2's have much trouble in that department with all the coolant capacity but I'm still using that to convince myself this is a good idea

As always, i start working away and forget to take photos, but here is where I'm at:
Used the old radiator to mock up mounts out of alloy, and cut up some spare rad hose I had lying about.
Factory fans will no longer fit, but they are far too heavy anyway so will be purchasing some slim 10" ones
Leaned forward quite a bit..

New position for rad

The bottom sits about the same height as the old rad support (which is now removed via drilling out spot welds)
I will be making an undertray/ducting that seals to the bumper
And provide protection to the radiator itself as the car is very low

Front view

I've cut the bulkhead, 450x250
Not a huge hole, but hopefully enough to expell what is consumed

Vent hole cut and soft edged

I wanted to make the exit ducting as straightforward as possible, and I didn't want a huge vent in the hood.
The ramp will start outside the frunk, so any rain water will not pool up in the wheel well and just land on the undertray
The hood cutout will be 450 wide too, but most likely a little taller

I figure with a raised section (like a gurneyflap) in front of the hood vent, the negative pressure zone will 'suck' the excess pressure being built up in front of the bulkhead just after the radiator and make up for the small vent size and such large radiator and entry
...but only time will tell

New radiator arrived

Onto the ducting next, before I take the scary step of cutting the hood up

[tomnomnom]

Revision 1

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[tomnomnom]

This was revision 3 of the exit ducting
Thought it was okay

Revision 3

Sat to far back though so got cutting again and this is revision 4

Revision 4

Revision 4 inside view

Revision 4 extra bracing

I think this will be the final design, I'm pretty happy with how it turned out
Might paint it at some stage, or maybe just wrap it

Still got to get some fans

Under car view

And make the inlet ducting, I'm out of material now though.
Not quite sure what I'll do with this, maybe a two story fin setup. Help push flow in the right direction
I don't want it to be too complicated though, and undo all the weight reduction I've done

[tomnomnom]

I'm getting better at taking photos of things I've done, kind off haha
Cut the rough outline of the bonnet, still a lot to do
Undertray is done, fans are in, front bumper is boxed
And still have some fab to do in the engine bay before wiring begins

[Benckj]

Like your design and interested in final result once car painted, etc. Front bonnet air duct should be interesting to see. Others with a similar design have had it collect loads of leaves & debris when car not in use. Depending on your garage storage it might be wise to install a trap door to flush clear.

Is screamer pipe going to stick out though engine lid or do you have other plans to conceal? I seem to recall that its legal to have a screamer as long as its located behind passenger cabin.

[85AW20v]

With those fans, you can cut out every second concentric ring to give more flow through them. They're quite restrictive - do a bit of calculation and you'll see what I mean.

You also need to make sure your opening is enough to let all the air through. I'm thinking that anything less then the size of the radiator won't be enough. I was talking to a guy at the 8 hour trackday I did on 1 November at Taupo, who races an SW20 in Lemons. They've done the same thing as you thinking it would hep with cooling but they now have overheating issues. By not having the opening the same size as the radiator, you are effectively reducing the size of the radiator to the size of the opening you've got. Well - that's my thoughts anyway!!

[tomnomnom]

Like your design and interested in final result once car painted, etc. Front bonnet air duct should be interesting to see. Others with a similar design have had it collect loads of leaves & debris when car not in use. Depending on your garage storage it might be wise to install a trap door to flush clear.

Is screamer pipe going to stick out though engine lid or do you have other plans to conceal? I seem to recall that its legal to have a screamer as long as its located behind passenger cabin.

Id say it won't catch more it did before, but I do expect it to require maintenance

Not sure what I'm doing with the screamer yet, looking to get a muffler for it for the tuning. Would be bloody annoying on the Dyno haha

[tomnomnom]

With those fans, you can cut out every second concentric ring to give more flow through them. They're quite restrictive - do a bit of calculation and you'll see what I mean.

You also need to make sure your opening is enough to let all the air through. I'm thinking that anything less then the size of the radiator won't be enough. I was talking to a guy at the 8 hour trackday I did on 1 November at Taupo, who races an SW20 in Lemons. They've done the same thing as you thinking it would hep with cooling but they now have overheating issues. By not having the opening the same size as the radiator, you are effectively reducing the size of the radiator to the size of the opening you've got. Well - that's my thoughts anyway!!

Good advice, I will look into that
The exit is something that had concerned me, but I'll have to figure it out once driving.
Thought it's better to start it small and I can always make the exit ducting bigger

[GDII]

I guess you want to create a lower pressure behind the radiator, not a higher pressure so it will allow air to flow though it less restricted.

[Malcolm]

The rule of thumb for sizing radiator inlets and outlets is 40% of the radiator frontal area for the inlet, and 60% for the outlet. The rationale is:
- the tubes and fins of the radiator restrict airflow to something around 40% of what you'd expect for the same area if there was no radiator there
- once the air has been through the radiator it should be a good 20-60 degrees warmer than when it came in, so to allow for this expansion you need more area than you did on the inlet.

Having said that, my similar setup has an outlet that is probably 40% of the frontal area of the radiator and I've not had a single issue with cooling. It's a fairly mild 3SGTE and I haven't done any track work though so take with a pinch of salt.

[tomnomnom]

I've also taken into consideration that the air leaving the radiator is much hotter, therefore less dense and easier to remove
A sort of gurney flap at the beginning of the hood exit will create a negative pressure zone (similar to our the engine lid/roof line works) and help pull the hot air out from the radiator pocket

But this is all theory and I won't know till I take it out, but keep the info coming

[tomnomnom]

Drew up some ideas last night and brought it to life this afternoon

Figured Louvres, especially at the rear of the hood cut (and the front apron) will stop any airflow trying to lift the hood

And it looks kinda cool I think, I'll have it tacked underneath and seal it with urethane after paint maybe
Still deciding

But I took some pictures again, I'm getting better at remembering. I usually just get stuck in with the music loud haha

E30 boot lid laying about, cut it up to make this
Bent louvres straight at first, but decided on a roll as well
Used some 2.5inch pipe we had

Rolling louvres

Clamped pipe to bench

Checking fitment

Still needs a clean up but this will basically be it

Very happy with how it's coming out
And it's cost my under $100 for the whole thing
I needed a new radiator anyway so not included in price haha


Still need to make an apron for it, not sure what I'll do there yet

[tomnomnom]

attachment=3]IMG_20201120_180255.jpg[/attachment]

Had to take it right back to metal, it's been sprayed a few times. Interesting to see what the rest of the car will be like

Smear bog it and prime it again then leave it till I'm ready to paint the rest of the car