what is the most efficient way to reduce underhood temps in our efs? especially during city driving etc.

 

ceramic coat your exhaust system, proven to drop temps a lot, run a proper oil cooler setup with thermostat, this not only cools your oil, it also reduces coolant temp and engine operating temp, and basic stuff like make sure your cooling system is operating right, dont believe in the myth of the lower temp thermostat, a lower temp thermostat only lowers the minimum temp your engine will run, not the maximum, maximum temp is set by the cooling system and everything around it, if you put a 170 degree thermostat in, the car will just run 170 as the lowest temp it can run, the temp can still go above that, it just means at any time above 170, the thermostat is wide open

 

thanks lost,... it seems like most of the heat is from exhaust manifold area i was thinking of venting my hood above that area is this a good idea??

 

won't do you much good, the cars are designed to vent under the car. the hood is sealed by design, as are the wheel wells. airflow is directed through the rad and under the car; venting elsewhere will disturb this path.

I used to wonder why the hell there was a giant plastic plate where my a/c condenser would be (half size rads in EJ6 chassis), so being 17 and very clever back in 1998 i took it off. 3 years later i understood airflow and path of least resistance, and put the plate back in. point of the long story being, honda knows best.

a rad in good shape, a working rad fan with the shroud, exhaust heat shield (or equivalent ceramic coating or wrap) are all good steps to take toward a cooler engine bay esp if you run a n/a SOHC as your signature indicates.

 

I've seen people use spacers on the back side of the hood (@the hinges) so that hot air can escape there. I wouldn't really suggest that unless you have some power adder to account for higher temps. Most things you do to the body will reduce highway gas milage, and only really help cooling on the highway. I know you said city...but this modification really wouldn't help you much there.

 

if there is a lot of city driving going on, you can hook up some pusher fans in front of the rad and wire them constantly on, or run them off a thermostat that you locate wherever you think your temperature problem is.

 

seems like when i switched to plm header thats when the heat issue began, i already have the hood proped about 1 inch. im goin to hook up a pusher fan like you recommended in front of the exhaust manifold. Im really concerned about the intake's iat i guess.
heres a pic for visuals

 

Lol, dude you must run a fan shroud. That slim fan is useless right now. And pushers can become a restriction at higher speeds. You have all the room in the world there to be able to run oem fan with shroud. As for better iats, run a cold air intake with a proper filter and ditch the short ram with screen.

 

if you are serious on reducing temps under the hood, spend the cash,ship your header to Jett Hot and have it coated, they coat the inside and outside with ceramic, this not only makes the header last forever, it keeps the heat where it belongs and stops radiant heat, I'm going to do mine this summer, but I'm taking them in person,as my header is too rare to risk shipping,also that fan has to go, factory fan and possibly AC fan too, wire them with a relay to both run, and use the shroud

 

im going to go to the junkyard and find a good working oem fan and put it on, then im goin to move this slim fan over and to the front as a pusher and see how that goes. im also goin to vent my hood around the exhaust mani