Before you go crazy about which heat sink and fan or fans you want to use...I don't want to disappoint you, E4RS does not allow TOO MUCH of room for you to mount the heat sink and fan, you can only mount the heat sink/fan pointing straight UP position, not to mention, hope your heat sink is not the full length type cause it will rub the rear little pulley.
The best heat sink to fit on E4RS is the K-Factory duo fan unit...HOWEVER, if you are using brushless motor (which you are)...your 3 wires, has to solder toward the REAR side of the motor instead of the shaft side like you used to do on your cyclone...
Get the car, mount your motor, and you will immediately realized what I was talking about...
I have not yet using any heat sink or fan to cool down my 17.5 E4RS...kinda good cause I want to see the actual temperature reading of the motor and I can push it to the limit. With a fan and heat sink...I might be able to gear 1 or 2 tooth more, but probably won't make too much of a different.
Awhile ago my friend did this to his E4RS just to hang it on the wall....I called it a ComEd edition E4RS...how many fans, plugs and wires can you found in this E4RS...? LOL
