Don't do a hood scoop. Must be a vent. A scoop pushes air INTO the engine bay. Your trying to find a low pressure area (usually found right after the radiator). The low pressure area needs the vent so the radiator's hot air is pulled through it over to the hood.
Well, this application needs a scoop to push air into the engine bay, specifically through the charge cooler which is mounted on top of the motor.
Just make sure you have high pressure on one side of your heat exchanger and low pressure on the other. Most people ignore the latter.
The motor looks a whole lot like this:
All I can think of is to cut a hole in the hood and add a fan on top of the chargecooler.
If you can't figure out good airflow, could you just add some ducting and move the charge cooler?
I hear the Taurus fans are all gone from the junkyards . . . I don't know, because I live in an area without junkyards. The Taurus fan isn't thin. It's like, 5 inches plus I heard.
Anyway, Volvos of the same era used an awesome 2-speed fan, if you have Volvos in your junkyards. You can get them new from RockAuto for about $110 a pop, not that I'm saying that's cheap.
People say it's comparable to the Taurus but you can pull it out of the shroud and it's a bit thinner, like 4 1/4" at the thickest part of the motor but 3 3/4 out towards the edges. I'm fixin to install one in my E36 swap this month. The Volvo 2-speed relay is the easy button to run it and there's a BMW 2-stage temp switch too. People run it with a 30 amp breaker no problem, so I assume the start-up current isn't much over that for a material time. I don't know what its running amperage is. Here's a popular link for the wiring info: volvo fan wiring
That big lump at the "front" of the motor is what I have to work around. 4" is probably about what the stock RAV4 fans are, and is too thick.
The guys that put that motor in the GRM MR2 would put one in a RAV for about six large. They move the charge cooler. Actually, they replace it with a HK$, I think, or some other aftermarket one. I think it will work on the motor with a scoop. Toyota had a air-water version on the 3rd gen and went back to the air-air on the 4th gen with a scoop. I think if it doesn't work out, I would try to find a air-water version and use that.
Sounds, from your "really thin" comment you are on it, but make sure it's behind the radiator pulling, not in front, pushing! They are a lot more efficient at flowing air.
RealMiniParker wrote: In reply to rslifkin: Yeah, that's what I was hearing from the V8 S10 swap guys. The Ford Taurus (forget what year) 2-speed single fan moves a LOT of air, but at heavy amp price. The LH body fans move almost as much, at much less amp draw.
The LH fans require a 40 amp circuit for low, and a 40 amp circuit for high.
I used to use 30 am relays but I was burning them out.
Alternatively you could wire it up with four relays, one for each speed on each fan.
I never amp-clamped them, but I can drop my idle speed 500rpm by turning them on. That's actually useful in city traffic 
Downside: Can't turn the fans on at night unless I turn the headlights off.
Fans usually have a big start draw and a lower continuous draw. Stated draws are usually the continuous. You've got to be able to handle that surge.
In reply to Keith Tanner:
I also melted a 14ga 30A fuse holder. The other one didn't melt but it got uncomfortably warm/soft when the fans were on. The fans never really are needed in normal use except for idle speed control, anything over 25mph is sufficient cooling. But in competiton, I crank the idle speed up to 1800 and turn the fans on and LEAVE them on, engine stays running in grid too. So startup-current is a good theory but they aren't frequently switched items.
This was the impetus for finally putting that FC RX-7 fusebox under the hood. All it does is provide fused power for the fans and the driving lights (big honkin' things that I never use because they are too bright, get blinded by the glareback from reflective traffic signs) but so far, so good.
It has been a long time, but I think everything is 6 or 8ga wire to where the power feeds Y out to the individual motors.
I was generalizing and providing info on fans in general. It's not a theory, it's in the specs for some fans. Takes more juice to get them started than to maintain speed. Check the ratings on your components, too - long continuous use can take out burly stuff. I've burned out golf cart solenoids with a long, relatively low draw.
Well, did some measuring and playing with what I've got. I need a 10" diameter fan that's 2" thick. Maybe 2 of those or maybe 1 and another that's 8" diameter. Modern Toyotas are way over radiatored, in my experience, but at 300 HP, I think some fans are still going to come in handy.
The stock RAV4 fans (Y2K) are 12" diameter and 3 and 4 inches thick. The 3" one was just a little too much everywhere for the left side and no way for the right side.
In reply to Keith Tanner:
AH, good points then.
If you want a funny example of startup current, certain vintage Audis had rubber mounted fan motors, and soft-start circuitry. Hardwire the motor to bypass the control module, and it will rip the mounts in half from the initial jolt.
Keith Tanner wrote: 2. You want a shroud that's well sealed to the core. No point in having big burly fans if they just suck air in from the sides.
It's funny.. this is the same fan my old Fiat 124 uses.. no real sealing shroud, just a metal ring around the fan that keeps air from sneaking in from the sides.. technically all it cools is a very small area (maybe a quarter of the radiator's size) area.. but it was enough to keep the engine at operating temperature.
You'll need to log in to post.
