TDYI

iTrader: (2)

Ok so i have an 87 na, i was interested in more space in my engine bay, my friend happened to have a black magic fan which he sold me for $10. I installed aluminum brackets that span the radiator and bolt on at the shroud mounting points on either side. I then attached the fan to those brackets so it it about half an inch above the radiator. It is wired to a relay to be on when the car is on, I have read the myth of the e fan and how to properly install one. ( http://www.aaroncake.net/rx-7/efanmyth.htm ) i plan on wiring it to the thermostat when i get a chance. My question is this, why does my car run hot at cruising speed only and not at idle and city driving? i know the fan is supposed to only run at low speeds, is the fan working against the air flowing through the radiator at cruising speed? or do i need a larger shroud to cover the radiator? This is the model of fan that i have http://www.flex-a-lite.com/auto/html/trimline-fan.html the straight blade one. it is mounted on the engine side of the radiator and is wired to pull air off. any comments are welcome including criticism.

clokker

iTrader: (2)

Have to see a pic of your install to have any idea.

Looking at the specs of the fans you cite, none of them pull nearly as much air as the stocker or an OEM unit like the Taurus (but that shouldn't matter on the highway).

Zomg-Rx7

Do you have the fan pulling air through or pushing?

Zomg-Rx7

Never mind didnt see you said that already first time I read it my bad

clokker

iTrader: (2)

Pulling is inherently more efficient and always the preferred first choice.

HotRodMex

iTrader: (3)

I think you solved this a bit yourself. Having the fan running while at highway speeds (Since you have it wired to "always-on") can lower airflow through the radiator, IIRC.

sharingan 19

iTrader: (16)

Without a shroud blocking airflow it makes no sense why it would run hotter at interstate speeds.

Black Knight RX7 FC3S

iTrader: (7)

Air flow will be a problem if your fan is also running. It will create turbulence. Something is causing the airflow to not flow through the radiator.

TDYI

iTrader: (2)

ok, so i was just out on the highway with it and it started to heat up so i turned the fan off, i dont think i was at cruising speed long enough though to really see any drop or gain in heat. i'll have to check the part number on the fan, but that type can range from 500 to 2500 cfm. i know it was on an rx7 before, so i'll have to find out what setup they had. i guess i'll just put the clutch fan back on for now because i daily it.

dimitry04

so wait. if you have the factory fan and fan shroud on. is it bad to drive it on highway? sorry dont mean to ask my own question in your thread but. highway driving is important to me since i go to school 25 mins away and to get ther in 25 mins i need highway...

jgrewe

iTrader: (1)

What do you have in front of the radiator? If you have removed any of the shroud there, that is your problem. The air needs to be forced through the radiator at high speeds, give it a small chance to go around and it will.

We don't even run fans on the race cars, but we are never below 4o mph. Any air that goes through the grill has to go through a cooler to exit. Fill every opening.

TDYI

iTrader: (2)

if you have the factory fan and shroud on you have nothing to worry about, your car is fine on the highway. i'm posting because i took them off and put on an e fan that is causing it to heat up at cruising speeds.

TDYI

iTrader: (2)

in front of the radiator is completely stock, as in between the front bumper and it, i will experiment more today on the highway for a longer distance with the fan shut off. if it acts like it should and cools without the fan i will just have to wire the relay to the thermostat.

dimitry04

oh. ok. i was just wondering. sorry man. i really didnt want to commandere your post. that would be a good thing to try. i think they are right that it may be doin more bad then good on highway or higher speeds. itll probably be fine if you have it off during highway

TDYI

iTrader: (2)

no worries, just wanted to make sure you knew your stock setup is fine. mine was fine too i just like how much space it frees up when you take the shroud off and if you're only running one belt, deleting the fan keeps the drag off the pulley.