Custom Placement for Air Intake Vent

[is_tech]

My AVATAR pic shows an intake vent on the driver's side rear.
I cut it from 1 pic, then pasted it into another to see what it would look like.
What do you think? A while back, I found a pic online of an MK1 with the air intake running through the hole in the firewall where the original intake ran, then had the filter where the original air box was. This way, you have a cold air intake that is not in the engine bay. Maybe it would even fit in the original air box. What are your opinions on doing this, then putting the driver's side vent on the car? You think I would get good sound? What about hp increase? Would it be more than the 5hp I gained when performing the Air Intake mod at
MKI MR2 Write-ups ?

[bspecmr2]

This mod has been done primarily to 87+ mk1s due to the fact that the stock air filter box lays right there under that custom installed vent. 85/6 vehicles had the stock airbox in the engine bay.
I wouldn't want to hack up the rear firewall of the engine bay to run piping to the trunk and have a side vent there, however it is probably the best option for 87+ cars that want to retain the stock airbox configuration while getting rid of the excessive piping running through the trunk, all the way to the passenger side vent.
I have had thoughts about cutting the rear 1/4 panel right there and putting a vent, but have not done it.
It does not look proportional to the passenger side. If you do want that fresh air from the side of the car vs. the hot engine bay and you already have the stock intake box mounted in the trunk like all 87+ cars .. a smaller cleaner cut can be made. V8Eater's blue mk1 had it done a long time ago. I do not have a photo handy to show, but it's a much smaller custom scoop alike hole in the side panel that directs air into the stock airbox.
Verdict is, you may not gain a whole 5hp, but you will gain cooler air which will result in the car running better.

[is_tech]

Cool!
Thanks for the reply and the info.
If I did decide to do this, I would not have to hack up the rear firewall of the engine bay as there is already a hole there where the piping ran from the MAF/AFM to the stock air filter box.

[is_tech]

Hello again.
I have received my new intake piping and installed it in the trunk.
I dont know how it sounds or anything yet because I have not hooked it up in the engine bay yet (need some flexible piping). Once I get what I need and see how it works, I may get some additional flexible piping and turn the intake around so that the filters face the other way. I tried holding it up there, and they go pretty far up into the hole where the stock air box was. Then I would of course look at possibly cutting a hole in the side of the trunk and putting a small scoop there. If I did this, then I could put the trunk trim back in place, and you would never see the filters. Any input on this, or should I leave it open? I was wondering whether or not you have seen this done before, and how you think it might sound. Also, do you think the gain would be anymore than the way I have it now? The way I have it now, the air really has no distance to travel, but the trunk hookup would be colder air as it is not in the heat of the engine bay.

[is_tech]

[is_tech]

Anyone have any input, advice, etc...?

Thanks!

[bspecmr2]

I feel that by doing a double filter setup you're making it bigger than it really needs to be. You can cut the side of the trunk and make an oval, or any shape opening and put whatever scoop you like on there. Also, a good thing in that case would be to build a box around your intake, that attaches to the side of the trunk wall so that it's completely isolated from the trunk and takes air only from the outside. You can get fancy with this or be real simple. Insulation of some kind could be used to keep heat out as well. I'm trying to dig up some photos I had before of the same setup, but can't find them yet.

[bspecmr2]

this one here for example, used the stock side vent and flipped it around, made the same cutout and installed it right where the stock airbox sits in the trunk.

http://members.shaw.ca/toymr2/MR2_Pr...yota_MKI.5.htm

i don't think he has any shots of the inside though, so that's not help.

[curvesrgood]

Just my two cents... the mk1 is already lopsided enough as it is with the single air intake on one side and none on the other... making one further back does nothing for symmetry. This is my solution...





We haven't made the cold air box yet that will come off of that pipe into the engine bay yet. Also we will be removing the battery perch there. I looked at what you're talking about in the pics above, and note that the vent from the other side is angled down... this will then be angled up on your car on the driver's side to allow for water to come in, etc... not to mention it looks funky with them angled up like that. I considered making a matching vent for the driver's side but then realized it wouldn't fit with the gas filler being where it is, so we had to shrink up the passenger side. This was rather involved, but in my opinion was well worth the time/effort. We are planning to sell this as a kit in the near future.

[bspecmr2]

nice that involves some serious modifications, as in cutting out the battery tray, relocating the battery to the front trunk .. and going with a different way to mount the intercooler on the SC cars.
I'm sure there will be interest in this setup. Some folks have moved the gas filler cap to the top, on the panel left of the engine lid, behind the pillar since it gets in the way of a symmetrical vent on both sides.
If i were to cut up my car I'd cut out the whole piece from a passenger side, make my own vent that's identical for both sides (which will bolt on the same way the stock piece does on the pass side), while using the rubber pieces and water collection, and route a filtered pipe into that.
there are many donors right now at junk yards for stock pieces to be cut out and fitted. it would make for a very clean setup and people can swap out different scoops to their liking, rather than cutting metal every time a different scoop is desired

[curvesrgood]

It was a bit involved... but we do paint/body work ourselves and have a shop so we could do all this stuff ourselves in a few days time . I actually moved the battery to the trunk instead of the frunk... used that same hole you used for the intake setup for running my battery lines through. I'm looking at relocating the gas filler on the stage 2 kit for my S/C car... which will definately be a bit involved! I'm glad some folks are looking at/are interested in body modifications for these cars other than the few choices out there aftermarket currently. I've had lots of interest in the scoops and engine cover so far, and I haven't totally finished either project yet (still have yet to cut the extra metal from under the engine cover, and haven't made that cold air box or removed the battery tray yet). After we got it painted Dad moved on to other projects (paying customers, lol) and we haven't gotten back to it yet. Since Dad is now quitting doing work for the public, we should get back to this one soon! I'm going to have to look at options for the S/C version of these scoops in regard to the intercooler placement. I'm going to be running the same stock intercooler as well on my S/C car so I'm looking at what options I have for that.

[q-authority]

I think people are making this far too complicated. After replacing my '85 MKI with an '87 (some dirtbag t-boned the '85 at an intersection) I realized how compromised the air intake system was on the '87-'89 models and devised a relatively simple workaround. Since I did not want to place any sort of new filter in the engine bay, simply because of the heat (and rain water), I had to come up with something else.
In the end, the solution seemed so simple I was surprised I had not seen anyone else try it already. For starters, temporarily remove the felt covered plastic partition that fits over the rear taillight assembly and then permanently remove the long stupid plastic air box/tube that connects the passenger side air intake funnel to the driver's side air filter box. You now only have the air intake funnel, up to the back of the electric radio antenna, on one side and the air filter box on the other. You can now reinstall the felt covered plastic taillight assembly cover piece.
This alone will help airflow to the filter box on the other side of the trunk, as the plastic connecting tubing is quite restrictive. But we won't stop there. Now remove the air filter box, from the driver's side corner of the trunk space after first removing its felt covered plastic trim piece. Temporarily remove the air filter and the cover piece that holds it in place (the piece that connects it to the engine bay air intake pipe). Now closely examine the structure of the rear piece of the air filter box (the piece that normally faces the against the driver's side trunk wall). After removing this piece from the trunk use a dremel cutting wheel, or similar device, to cut away all non structurally necessary pieces of this part of the air filter box. Leave only the portion that is necessary for retaining it to the trunk body and for properly holding the air filter in place when it and the compressor side of the air filter box is reinstalled. When you have cut away as much material as you feel comfortable with, reattach this piece of the air filter box to the trunk body, reinstall the air filter, and reattach the compressor side of the air filter box with its three clips.
You could stop there if you want, as you will have considerably better airflow than previously, but there is one more step that will help even more. Remove the passenger side felt covered plastic piece that fits over the electric radio antenna and trunk air intake funnel. Target the large air intake funnel that directly attaches to the passenger side air intake vent bellows. Cut away, from the top side of this piece, whatever size piece of plastic you feel comfortable with. You will now have free airflow from this new vent and from its original connecting hole, located just past the antenna in the corner of the trunk. Do not cut away any bottom portions of this funnel piece (or remove the whole piece for that matter) as there is always the possibility of water getting back into this section and it contains a drain pipe located just behind the radio antenna. If you leave the two felt covered plastic pieces off you will have as good as or better air flow than will ever be required by the engine. You would now have to really jam the trunk absolutely full of stuff to really interfere with it that much.
You can reinstall the two felt covered end pieces, but I have found that this will reduce the air flow somewhat. Since I don't really care about having them in place I have left mine off and have gained some slight extra trunk space in doing so.
However, when I finish with my '89 S/C project I plan on using a hole punch of some kind to place air vent holes in both end pieces (in a pleasing pattern of some sort) and reinstall both of them.
Either way, you will now have fresh cold air to your engine air intake and as much as it can use according to my testing. In fact, I also determined after having performed this that the K&N filter designed for the trunk mount air filter assmebly is not as efficient as the stock air filters. That's correct!! Sorry K&N, but your design for that placement sucks. Try it yourself and see. The results will be a bit more than obvious. Once I figured this all out I tried like hell to find a TRD air filter for the application, which was a cleanable filter, but with a stock air filter design, but unfortunately they have not been available for some time. The reason why the K&N does not work as well is due to its smaller overall surface area. The stock filter also usually has much more surface area that the filters used for mods that are placed inside the engine bay and there is now no worry about keeping it dry as well.
My '87 runs incredibly better with this mod done and I can’t wait to do it to the ’89 S/C.