In hopes to minimize the amount of heat being drawn into my air filter, I’d like to rotate my 90 degree intake filter elbow 180 degrees to place my filter in the other side of the firewall.
As of now, my filter sits about 4” above my mother.
I haven’t seen anyone with a set up similar to what I’m contemplating. Do any of the experts here see any challenges/issues/problems that this will cause that I may have over looked?
thanks in advance!
-Sean
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Here's the way the VW Karmann Ghia moves the air cleaner off to one side (for hood clearance).
Thanks WG! I have LOTS of room to relocate the filter inside the engine bay. I even thought I’d tucking it behind the bumper-latch mechanisms, fabricating an aluminum shroud to force air from under the car and drilling holes behind the license plate to five air circulation. But my thought process was to separate the filter from the bay altogether. I know the firewall hole is needed for the P-car and VW fan shrouds but that’s not so much the case for a Subaru motor.
I cant think of any other purpose that that hole serves me (TWSS) and my application.
I didn't think that looked like a Solex carb . I don't think it matters where its placed. On other side of the "firewall" would just make it difficult to check/change the filter but that would only be every 20k miles so maybe years.
Like the carbon fiber.
No carbs on this thing. It’s all FI. I just took the filter off to get a better look at the situation
Gonna give it a a shot. If it works, I’ll post the results and PCs for others JPS Soobie owners.
One Stripe posted:
In hopes to minimize the amount of heat being drawn into my air filter, I’d like to rotate my 90 degree intake filter elbow 180 degrees to place my filter in the other side of the firewall.
As of now, my filter sits about 4” above my mother.
I haven’t seen anyone with a set up similar to what I’m contemplating. Do any of the experts here see any challenges/issues/problems that this will cause that I may have over looked?
thanks in advance!
-Sean
There's room in the engine bay for a Subi AND your mother? That's real nice of her to hold the filter high enough to catch air. Bwaaaaa Haaaaaaa
Damn you autocorrect! DAMN YOUUUUUUUUU!!!
lol
re-reading this whole thread makes me chuckle. Mother...carb...heat.
Is heat really a problem for your motor?
Cold air always results in better performance. There are many aftermarket cold air intake kit out there that take advantage of bringing fresh unheated air. I doubt he had under hood temps like an air cooled engine but then he doesn't have the air seal to keep out under car hot air either. Remember the old Firebird's with the shaker hoods.
I can see no issues with running the aircleaner out ahead of the firewall in your installation, other than getting to the filter to clean or change it when the time comes. Remember that the engine rocks slightly under operation, so make provisions for that potential movement with a large enough hole and you should be all set.
On Bridget I put the air filter forward and on the driver's side, basically above the axle. I did this for space reasons but was happy to have a high-pressure, cold air spot for the new cone air filter, and the longish intake piping gave me plenty of room for the MAF sensor and all the various random vacuum hoses and junk the Subie had (I used the stock ECU and so strove to keep everything just so). Plumbing was easy; all the tuner boys are fabbing up 3 and 4-inch "cold air intakes" for their monstrous creations so the FLAPS now carries that stuff. If I were doing it again I'd buy the elbows and junk here.
So an air intake from forward of the firewall is good but having an oil cooler there is bad?
Yes.
Bill Prout posted:So an air intake from forward of the firewall is good but having an oil cooler there is bad?
If the engine (air or watercooled) is drawing cool(er) air from in front of the firewall then it's a plus. Pre-heating the same air with a cooler before it enters the engine compartment is counter-productive.
Actually...I did have an issue after I drove it (city/highway) REALLY hard for about an hour not to mention sitting in traffic in between runs (during that video) with the A/C on in 95+ degree weather.
Doing multiple runs of 80mph, sitting in traffic, and dogging it out over and over again we stopped to get the last shot.
After sitting for about 5 minutes, it was slow to crank over. When it did, the motor wouldn’t stay engaged and it sounded like it wasn’t running on all 4 cylinders...almost like there was a loose plug wire or there wasn’t enough fuel being fed to the injectors.
Not wanting to take a chance of having an engine failure on the highway, I towed it home. Once the tow truck dropped us off, I jumped in, turned the key and it started with no problems.
Fuel pump is good. Fuel filter is good. Fuel injectors are good. Radiator and fan are good. Coolant levels are good. Oil is clean.
I called my Subie engine swap expert here in Dallas and he said “move that damn air filter that’s sitting on top of your motor. It’s sucking up hot air after running it too hard and the ECU is telling you ‘you ain’t going nowhere until you calm the f**k down!’ Problem solved.”
So, after checking the clearance aft of the firewall, I don’t have enough clearance to run a 3” pipe in that firewall hole. Looks like inside the rear bumper will be my next option.
I don't know your fuel situation, but some manufacturers use a plain old low pressure pump in front to feed a surge tank in the rear. The surge tank feeds the hi-pressure EFI pump, then to the fuel rails and then the regulator with the excess going back to the surge tank.
Sometimes when you run them really hard, the fuel pump up front gets a bath of hot air from the front-mounted radiator. This can cause no fuel to get to the surge tank. If the hi-pressure pump is in front or in the engine compartment, heat from either the radiator or engine can overheat the pump.
Was the fuel pump especially loud when the engine had the problem?
Danny...I couldn’t tell. The sound of the motor running rough was louder than usual (like it wasn’t running on all cylinders).
It’s probably the the last time (yeah right) I’ll run it that hard. I had it up to 95mph on I-30 before it hit me...I’m in a fiberglass shell with no ABS, no air bags and no structural protection. The steering was true, the brake response was tight and the ride was crisp!
It was smoother than my F-150 and my wife’s Tahoe! It still wanted to pull. The specs from JPS says 250hp, but I find that hard to believe in a non-modified EJ25 motor.
One Stripe posted:The specs from JPS says 250hp, but I find that hard to believe in a non-modified EJ25 motor.
That's the patented JPS Orange County Correction Factor (although he was in LA County until recently).
I've had my little clown car up to 120 or so (indicated), but it isn't very fun. I'm unconcerned about the fact that it's made out of fiberglass without modern safety accouterments (I used to ride big bikes)-- but the fact that the front wheels so desperately want to leave terra firma gives me pause (or pucker, I can't decide which). I think that's what struck me so much with the two IM6s I've driven-- the 911 front ends keep the car planted for as long as you want to keep your right foot in it. I've not hammered on Marty's IM-Sub, but I'd bet it's just as stable.
One Stripe, interesting that you drove your car hard for an hour with no problems. The weirdness started only after you parked it for a short time and restarted. And, when it had a chance to cool, the problems went away.
Carbureted, air-cooled engines in the same engine compartment are subject to the same issues. With carbs, it's assumed this is caused by unvented heat causing fuel to percolate in narrow passages in the carbs and fuel lines and taking a while to clear after the restart. Could be the same is happening in your fuel-injected engine?
Either type of engine will be at its hottest for 10 minutes or so after a shutdown. Maybe try running it hard again and then parking it but with the engine bay lid open to see if the symptoms return?
Sounds like a good plan. I bought a thermal gun to measure the engine temps. I know it’s only providing external and not true internal temps but it’s data that I don’t currently have.
I started the motor last night. No issues. Let it sit for about 20 minutes with the motor running and A/C on. Rad fan came on about 10 minutes in. Cabin air was at 45 degrees. Outside air was at 90. Manifold temp was at 120 and oil gauge read 150. The ceramic coated exhaust fluctuated between 300-350 on the outside BUT inside the exhaust top wa 110? Of course I had to do the “hot stove” test and stick my finger in the tailpipe (insert joke here). Yep...it wasn’t hot on the inside.
Hopefully I’ll be able to drive it this weekend and see if I can higher engin temps.
When I did that video, the oil temp gauge never got higher that 210, which both my Soobie and VW experts say are optimal ranges. But they both shared the same concern with the filter placement. I’ll share photos when I fabricate my intake plumbing.
