richlrx7

Here is a project that I completed a few weeks ago on my GSL-SE. OK, this may be a bit lengthy, but I thought that it might be helpful to anyone that is thinking of doing the same. I'll be real happy to answer any questions if you have them.


GSL-SE Cold-Air Intake Mod


The following is a fairly simple low-cost mod you can do to eliminate the stock air-box and increase the air-flow to the intake system.

It ain’t hard! It ain’t too expensive! It ain’t too ugly!!

Parts
1 - Spectre Intake Kit #8216
1 - “ 45 Elbow #8738
1 - “ 3” Sensor Adapter #81413
1 - “ 3” Coupler Kit #8771
1 - “ Cone Filter #8136
4 – 3” SS Hose Clamps
1 – 3” Exhaust Pipe Clamp
1 – 1”x.25”x12” Aluminum Flat Stock

Misc. Notes
I used the Spectre Intake Kit because I already had it. You can get a plain untapped 45 pipe from Spectre. I shortened the #8216 pipe by 5 inches and capped the sensor bungs.

Procedure

1. Remove the following:
a. The hood.
b. The top radiator support panel just in front of the radiator.
c. The stock air-box assembly, including the front inlet air ducting from the air-box forward through the right-side radiator mounting panel, across the front of the radiator to the left-side radiator mounting panel, AFM (Air Flow Meter) and lower half of the 3” molded- rubber intake hose connecting the AFM to the throttle-body. Do not remove the air-box mounting brackets.
d. The front grill.
e. The right-hand horn assembly w/ bracket.
f. The coolant overflow tank and mounting bracket.
g. Any misc. crap that you don’t think you need.

2. Detach the already removed AFM from both the lower 3” molded-rubber section and from the air-box adapter.

3. Use an electric jig saw or other appropriate tool to open the existing hole in the right-side radiator mounting panel, so that the 3” pipe from the #8216 kit will fit through at about a 45-60 degree angle. Be sure to clean the sharp edges up with a file or grinder.

4. Relocate the already removed right-hand horn assy. to the center of the header-panel attachment bolt just in front of the radiator.

5. Attach the 3”x2.5” rubber reducing coupling from the #8216 kit, to the inlet end of the upper 3” molded-rubber intake hose, using 3” SS hose clamps. For more clamping area, I replaced the stock short metal inner sleeve with a 2.5” section of the piece that I cut off the 3” aluminum 45 pipe from the #8216 kit.

6. Attach the 3” Sensor Adapter #81413 to the AFM using the original AFM/Air-box adapter bolts. You may have to use a flat washer, with the side partially filed/ground off, on each bolt to act as a spacer due to the slight taper of the adapter at the base. The adapter has a bung for an air-temperature sensor but I left it plugged, and will relocate a new temp sensor closer to the inlet behind the new filter.

7. Re-install the bracket and coolant reservoir tank.

8. Next, take the 3” 45 degree bent tube, 3” hose clamp and the smaller aluminum bracket from the #8216 kit and slide the tube through the right-side radiator mount opening. Attach the small bracket to the spot where the right-hand horn was originally located, then bend it to match up to the 3” tube, and install the clamp but don’t tighten it yet.

9. Take the 1”x.25”x12” aluminum flat stock and drill a hole in each end to match up with the two forward most holes in the mounting brackets of the original air-box, then attach it using the bolts that came from the air-box assy.

10. Now take the 3” 45 Elbow #8738 and use the 3” Coupler Kit #8771 to attach it to the AFM, then loosely connect the entire assembly to the 3” molded rubber intake hose and to the 3” aluminum 45 pipe you previously installed through the right-side radiator mount. Make sure to rotate the AFM 90 degrees so that the cable connector is on top.

11. With the whole assembly slightly tightened, take the 3” exhaust clamp and slide the saddle part of the clamp so that it acts as a cradle between the 3” 45 Elbow #8738 and the aluminum flat stock bracket. It will sit slightly askew to the bracket. You will need to file/grind the inside of the saddle to accommodate the slight angle. Once lined-up, mark and drill the holes for the u-bolt.

12. To finish, tighten all the clamps and brackets. Be careful when tightening the u-bolt around the plastic 3” elbow. Connect the cable to the AFM and zip-tie the cable/wiring harness to the AFM body to relieve the weight of the cables from the connector. Install the cone filter to the inlet of the 3” aluminum pipe in front of the radiator, then re-install the top radiator support, the grill, and the hood.

Operational Notes
The filter is easy to access for cleaning. Just remove the two left screws on the grill and pull it out through there. A primary concern was, that with the intake assy. being partially in front of the radiator, there might be some blocking of the air-flow to the radiator, causing a higher engine operating temp. Actually, I have seen just the opposite. The engine operating temp has dropped by at least 10 degrees. BONUS!!!!!! Definate improvement in air-flow. A secondary concern was with water/moisture getting into the intake. I have driven through severe rain storms and have had no problems at all. Apparently, the filter is back from the grill opening just enough and is pointed slightly down so any collected water/moisture can’t flow further along the intake.

Good Luck!!!

I'll drop some pictures in as soon as I can figure out how!!!

John64

Need pics.

SF@Rx7

sound interested
pic will be great

riceburner1r2001

iTrader: (4)

yeah 85 se right here.com

Max7

Nice writeup, can't wait for the pix

nikstet

definately need pics

Rx-7Doctor

iTrader: (13)

Looks like you did some go work there Amigo.
Alittle tip to finish the job and get the most benefit. Relocate the Air intake sensor from the
side of the plenum to the Cai piping. This way the ECU will read the colder air and optimize the HP.

Max7

Why not move the sensor into a bucket of ice? You've only tricked the ECU into making it think its colder. If the CAI works the air at the plenum will be cooler.

richlrx7

Thanks guys! Yeah, I plan to relocate the air sensor to the front of the intake just behind the filter. Now for the big question.......can anyone tell me how to post the damned pics???? I've tried 4 times, doesn't seem to work.

Rx-7Doctor

iTrader: (13)

Because my friend, the air inside the plenum is not as cool as the air coming thru the CAi.
The plenum is sitting ontop of the motor and gathering heat from the engine bay and the motor.
Ps; doing this is not tricking the ecu, it's reading actual cooler air. Tricking the ECU is changing the resistance value of the sensor without changing the actual temp of the air entering the system.

richlrx7

OK, here's the deal on the pics. Until I can find a site to host the 2.6 MB file with the pics, anyone interested in them can just PM me with their e-mail address and I'll be happy to send them the file. Happy Hump Day!!!!

d0 Luck

a dyno sheet would be nice too. i highly doubt a CAI will do any better than a replacement aftermarket filter since it's all held up by the restrictive AFM.

gsl-se addict

iTrader: (3)

I'll can host them for now. I will lose my space in a couple months, so someone else will have to host them later. I'll send you my email address through pm.

Kent

richlrx7

Actually, I did run the stock box w/ a K&N filter. I did notice the difference with the mod. You are right, the AFM is restrictive, but I didn't feel it was worth replacing/upgrading. As far as the improving the inlet flow, just take a look at where the stock pre-AFM piping runs. It routes from the AFM, through the air-box, through the right-side radiator mounting panel, across the front of the radiator back to the engine compartment by the battery. I guess they had some good reason for all that piping just to suck hot air from the engine compartment. I don't know what it is though. I'd be curious to find out.

Max7

I don't want to argue in another persons post. But show me where people do this.
All your doing is riching it up, cheating the ECU. that cold air out there gets hotter by the time it gets to the engine. so where are you thinking this will help? And please start another post with this subject, I'd like to talk more about it....

LongDuck

Mazda designed the stock air intake system on the 84's and 85's SE a bit differently, since cars in the 84 model year came with a pipe that only extended about 1/2 way in front of the radiator. The problem with this mounting was that when the car went through water of greater than 2" depth and speed greater than about 10-15mph, that water would be thrown up and sucked into the intake, settling in the low point of the piping and stalling the car.

Once Mazda figured out that this was a problem, the 85 SE's were modified to use a pipe that went all the way across the front of the radiator and through ANOTHER hole in the radiator mount behind the battery. This draws air in from behind the battery which is protected from water, but unfortunately subject to underhood temps.

They had the right idea by giving it a stock CAI, but the execution left a bit to be desired. You've put a lot of work into your CAI install, and I applaud you. Here's mine, using a Mariah lid vent and the stock ducting into the stock airbox (w/K&N):

Looking up the lid, you can see the filter in the box, it's almost a straight shot:


And the piping to the airbox itself:


To host pics, go out to "www.tinypic.com" and host your images there - they even allow for simple and easy cut-and-paste of the [img] and [/img] symbols - use the "Img" text. HTH,

richlrx7

LongDuck, Thanks for the insight into Mazda engineers thought process. I thats why they're always trying to improve on old ideas. Throw one out and see how well it works. I like your intake. Very clean. Nice car. Have you noticed any problems with excessive amounts of water/moisture getting in?

gsl-se addict

iTrader: (3)

Okay. Here it is, guys.

www.oregonstate.edu/~abelk/Manuals/CAI%20Mod.pdf

Nice work, Rich.

Kent

richlrx7

Kent,
Thanks and thank you for hosting it.
Rich

LongDuck

I've driven the car in pretty heavy rain with the headlight lid in the 'down' position which should let some amount of water get in. I didn't notice any decreased performance, but I also designed it so that there is a gravity water trap at the edge just inside the front of the engine compartment, so that any water that makes its way in there drops down into the crack before it enters the air pipe.

I usually drive with my headlights on and up when it's raining, but have come to the conclusion that if I need my windshield wipers, I turn on my lights - just to be safe and not get the filter soaking which would choke the car. HTH,

1984special

LongDuck,
Are you running the headlight intake in addition to the stock 84 setup? Any more pics?

Thanks