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3,180 Posts
Discussion Starter · #1 ·
Hey guys, this is my cold air intake project. I also tapped all my intake runner for vacuum and re-configured a PCV system with catch can and VC vent to my new airbox. The airbox and plate is made and sold by my dyno tuner BOI Performance and the plate was machined specifically for my car.

Cold air runs through a 4" duct via large K&N pod filter in a high pressure zone external to the engine bay.

So far the results are less heat-soak induced loss of throttle response in stop-go traffic situations or hot days, but the dyno results are yet to be seen. I am expecting a little more torque across the range with a boost in top end HP, and this is what I have seen on other dyno runs that have upgraded to this setup. Subjectively, the low end response did feel better.

Test fit airbox:

Carbs off to tap IM runners, and finishing touches on airbox back plate:

New threads:

Modify the throttle linkage while I'm at it for adjustable throw:

Back plate fine tuned and fitted:

Refit carbs/mani to engine:

Fit the backing plate, and notice the shorter throw on the accelerator linkage:

Seal and dampen the air box:

Checked out the corner to clear the PCV VC vent fitting:

Box done:


3,180 Posts
Discussion Starter · #2 · (Edited)
Make like Mario and do some pipe works

Bumper off, horn off, find a good spot for filter!

Battery relocated to trunk, so air duct will route down through this cavity and through the panel:

From the front, this is under the light:

Cut 4" hole:

Duct goes here:

Filter Time:

Old K&N Oval filters compared to the air box, now has more air volume around the trumpets, and more back space in front of the trumpets, should net less air flow restriction and more air flow inertia with the duct length.

New Filter:

Make up a Joiner piece:

filter to duct test fit:

View under headlight, bumper going back on:

Bumper goes back on:

Pod sits just above and behind the "fog light" recess:

Look from underneath - next stage is to fabricate a block-off plate back under the bumper to form an air scoop / high pressure boxed area.

Duct runs this way:

Finish the vacuum line plumbing, vacuum distribution manifold, PCV system and catch can:

For some reason I don't have a 100% finished engine bay pic so I will have to go and take one soon. Since then I have a new Blaster 2 coil and have neaten up the bay somewhat. Also have done a new custom radiator install LOL, onto my third radiator, 2nd custom install, in the last 6 months, new brackets made up for this one, a full Tig welded ally unit this time from an AE86 but that is a story for another thread... stay tuned...

Lord Magnum
1,210 Posts
I really like the look of that thing. I was checking out their site...looks expensive.

On the other hand, the look of open air horns is pretty nice, too. :)
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