Just like the title says. This is a thread going over on LS1tech.com.

http://www.ls1tech.com/forums/showth...5&page=1&pp=20

 

I have been monitoring that thread and I think it is a good idea as long as you can get enough cfm through the IC to make it worth while. In fact, I am considering putting some small fans on the two smaller ICs on my D1SC setup to help improve their efficiency at low speeds. I would only go to the FMIC as a last resort because of mounting/airflow issues. I don't want to cut up my bumper or bumper cover. Thinking about something like this:

ATI Intercooler Fan Kit

click on LS1 Fan Kit.

This will likely require a higher output alternator (as will any fan setup for a FMIC), but I have found 200 amp units for the LS1s.

Sorry dial up users, this can be a little slow.

 

If you are running that high amp fans on a FMIC, I have no idea why you're doing it. If you want an extra 70 Amps of power at 12VDC, that'd be enough juice to do a LOT of things, many of which more efficient then a FMIC ever would be. You could get a small air conditioner running 12VDC and have it chill a water tank to -20degF with coolant in it, or something like that.

70A is a rediculous amount of power. You're talking more power added then many imported cars have (not the factory use of 65A alternators) That's just stupid.

Proper ducting is the key to any intercooler, radiator etc. Our cars suck for space and ducting of a FMIC. We know this. Honestly considering the size of an air/air core needed, and thusly the fans, if you really want to do that, your best bet is to go air/water and do it that way. Then you are only limited by the heat exchangers - and a pair of 11"x11"x1.5" heat exchangers for air to flow through will be more then enough to keep things running in an air/water setup.

If you have ducting done really well, you take the core front surface area and divide by 3. That is the approx frontal surface needed. More is better sure, but not really necessary. That assumes GOOD ducting.

Also no matter what you do with fans, if you havent ducted well, you will change the pressure diff across the fans and core - which may drop your cfm numbers dramatically. Those guys have ideas, but they dont seem as concerned with getting air out as getting it in.

If you dont want to hack up your nose at all - go air/water. Otherwise, hack away and do air/air. Anything else will be a lot of finesse to work properly. It can be done, but it's not easy. And when it's done properly, you dont need fans, or want them at all.

A FMIC at high speeds will do great. I bet the fans will be a restriction though at that point, and you wont be at low speeds for long.

 

I did not mean to imply that a 200 amp alternator would be required to run the fans, rather that these are the only replacement alts I have found. The stock alt only puts out 102-106 amps. This barely runs what comes on the car, let alone anything else. The 200 amp will run the additional fans with plenty left over for big or multiple fuel pumps, a sick sound system, whatever. Also, they can be had in natural, black powdercoat, or chrome. Unfortunately, they are expesive running from around $350 for the natural to around $435 for the chrome. This, plus the fan setup, and you are easily looking at $500+. This much money may very well best be spent on alternative IAT solutions. It is just another option for to consider, and I agree that fans mounted on any IC will likely become flow restrictions at higher speeds....good point....unless they are big honkin' fans. Fans can be noisy, too.

Tom

 

True.

My 135A Alternator however runs my car just fine. I will admit I do not have an aftermarket audio system, and never will. I do have an electric water pump that runs all the time though.

However in contrast I have an additional pump running to circulate my water in the intercooler, though that draw is not large.

During WOT runs though, I pick up a 2nd fuel pump, a methanol injection pump, and several other devices. I also have fans on the heat exchangers for my intercooler setup, but those are temperature sensative and I am guessing at most a 50% duty cycle while the car is running, and they probably will run much less then that.

I have plenty of current to spare. It is possible - though when it comes down to splitting hairs, I actually think gettings fans is a poor solution to the ducting problem that plagues our cars. It is a solution though, just as sticking the turbo in the back of the car. It will work, but not necessarily as efficient as something more ideal.

We'd be better off getting vented hoods me thinks.