Powermax

Powermax Filter Modification

Below is a picture of my engine compartment with the relocated MAF and Powermax filter. You can see how it's in a straight line with the intake and the stock plumbing is completely gone.

[IMAGE]

This mod was worth 5 hp and power all the way through the rpm band on the dyno. (See dyno charts). I have some plans to pipe the intake to the front of the engine bay in front of or below the battery to try to get cooler air, but that will need to by dynoed too to see if it does anything. I am also trying to get a "Rytek" aluminum shield for the filter to protect it from rain... I'll post that when I get it installed.

You might also notice the Jet Hot coated valve covers, the Jet Hot coated TRD header, and the Magnecor wires. The Jet Hot does a great job of keeping the underhood temps lower and besides, it kinda looks cool! :-)

Here is the original text from my filter mod post:

I've received several requests for info on removing *all* the intake plumbing
on the MK1, so here goes (this gets long)...

The MK1s have a rubber pipe that goes from the MAF to TVIS. On the 85/86 this
pipe is about 8-10 inches long and has a slight bend, on '87/88 the pipe is
longer and has two severe (90 degree) bends. This pipe can be replaced with
a single, straight rubber pipe about 3" long for around $5. Procedure:

85/86: Remove *all* the intake plumbing including the airbox, rubber hose,
MAF, filter, resonance box, etc. This will require you to remove a couple
bolts and brackets, disconnect the MAF, and (if you have air conditioning)
disconnect the vacuum line for the idle-up circuit (?). You will now have a
BIG hole where the airbox used to be.

Measure the inside diameter of the rubber pipe or the outside diameter of the
TVIS side of the pipe. If I remember right it's about 2.5 inches (65mm or so).
Go to your local hardware store -- I've seen the rubber pipes at Builder's
Square, Home Depot, and the local stores, so they're common. In the pipe
section you'll find several diameters of a rubber pipe with wall thickness
of about 1/4 inch (7mm) and about 3-4 inches long. Choose the one closest to
the diameter you measured... don't rely on the writing on the package, for
some reason a 2" pipe is really something like 2 3/8. It should be under $10 and
is made by PlumbQuik and is the 2" to 2" pipe coupling.

The MAF diameter is about 1/4 inch larger than the TVIS side, so once you have
the pipe you'll have to MASSAGE (stretch) the pipe onto the MAF. This is
difficult because the rubber is stiff, but it works (stretch it with your
hands first, then work it onto the MAF in a circular manner). Clamp it in
place and go back to the car. The other end of the pipe will slide right onto
the TVIS.

Next you'll have to make some brackets to support the MAF because you've
moved it closer to the opening in the hood (higher in the engine compartment).
Simple brackets will work, and there are plenty of places to bolt them down
inside the engine compartment (thanks, Toyota).

If you have an '85/86, you'll need the adaptor to go on the end of the MAF.
This is a small cast aluminum plate that bolts to the MAF where the airbox
was and provides a round flange to mount your filter on. This can be bought
from Select Sales, Options, or Cyperspace Automotive. The '87/88 already
have this built into the MAF so you won't need it.

I installed the Select Sales cone filter, which *just* fits inside the shock
tower. This is a nice cone filter, but I suppose you could use K&N or any
other filter of 6 inches or less.

If you don't have air conditioning, THAT'S IT! You're done. It took me
about 2 hours. If you have air conditioning, you need to figure a way to
reattach the vacuum line. I attached mine by drilling an undersize hole in
the side of the tube and threading in a standard air fitting with an interference
fit. I had no leaks or problems with this setup, and it was easy to do.

I think that's enough for now. If there are additional questions feel free
to ask. The '87-88 cars are similar but the airbox is in the trunk and there
is considerably more plumbing to remove. All the directions still apply.

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