Thread: hood spacers anyone doing this

When you guys say your temperatures were dropping were you paying attention to driving the same way in the same location with the following equivalent conditions?

Throttle/RPM
Oncoming wind speed
Road level
Sunlight angle and intensity
Ambient temperature
Ambient humidity

Because unless you can be sure about all of these things, it does not necessarily mean that big of a gain came from spacing the hood. I understand the fluid/heat transfer effects which cause the phenomenon, I just mean to say that some very controlled testing would be needed in order to verify that 10 degrees of drop was just due to spacers.


The flow conditions are not only impacted by the gap created, but by the hood angle. This is how it would be different.

Jen just pointed me in this direction, so here's what I have to say about it: I know this is lame to say, but I recall recently reading an article (more than likely Modified) and they tested the theory and only saw a 2-5 degree temp difference. Now if you need that little of a temp drop and you dont want to spend more than $5 then go for it, but I wouldn't go bragging about it. If you want significant temp drops, get a bigger radiator, an upgraded thermostat and a DIY oil cooler (the oil cooler can be done for $100 give or take).

Also I know the other argument is that it allows for a good amount of air to flow out of the engine compartment, but in my opinion...not really. In most cars/trucks the pressure area in front of the windshield/back of the hood isn't ideally placed to suck air from the engine compartment. Most engine compartments are meant to pull air through the rad/condenser cores and then get pulled back down from the bottom and it is engineered for that, not for going up through and around engine block and then out the hood.

Another note, if you're running without an engine undertray and do this mod it's probably even less effective considering your largest pressure release is below your engine and in most cars, people have seen benefitial temp results running OEM or modified/custom undertrays.

So I wouldnt go giving this "The cheap mod of the year award"

im running a koyo R radiator, nismo thermostat. but whole turbo setup is all custom and it doesnt give alot of room between the turbo and the radiator, so i have the turbo,radiator,downpipe,intercooler piping, all in close quarters which heat soaks alot of the parts. now its not heat soaking to the point where its a problem, but your normal heat soak. so a bigger radiator,better thermostat, isnt always going to be sufficent or efficent enough to cool down hte engine better when the application itssself generates a decent ammount of heat which all turbo applications do.

as far as my testing, no i havent taken ALL of those things into consideration and in reality, i havent taken ANY of those things into consideration, and while they might be suifficent in actually gauging weather or not this mod actually works.

so far i have noticed that at normal operating temps with the mod, the hood is alot less heat soaked, where the turbo and manifold is where as before it was really hot to the touch on the hood, it is now mildly warm, nowhere near the temp as it was. i do think it is working better for me, as like isaid my application has close quaters and non heat wrapped. it does seem like its working better.

ONCE AGAIN!!! Another trend the honda boys stole from the 240sx crowd dam the trend rippage just not stop for the honda boys huh? First the muffler charms >>http://www.sr20-forum.com/offtopic/21106-muffler-charms.html now the hood spacers.

topdog just go away your an idiot

be nice, hes had enough **** from people on here...lets not provoke a flamewar outta this thread...

Shhhad AP!

i went by all listed above as u listed and from making my hood flush factory to rising the back of it and removing seal, car went from 189f to 180f on a 95degree day at 85mph at around 4000 rpmish. These cars are notorious for heat soak. All temps where sourced from aem digital gauges and nissan data scan. I did mulitple freeway runs running with and without spacers and the most gain i saw was about - 10deg. If it didnt help that much i wouldnt do it but in the name of keeping the car running cooler and longer in this wicked fl climate, i dont care if my hood is lifted in the back. WHO GIVES A FLYING F***. if you dont like it then stfu. Once you fags talkin **** get into the boosted world, I bet you be looking for little tricks here and there to help cool the car down. U cant even talk if your na with a stock setup. These cars with ac run much hotter.AHHHH newbies

i have a very large turbo and the only true way to test it is to get rid of all variables that could change every time. You driving on the highway is not a test that will change my mind there are to many variables that you fail to see but im a newb so what do i know.

Relax, I'm not trying to bash your hood spacers. I was only trying to put them up to a fair test, just like you should with ANY mod from an air filter to a turbo. The fact that my car is N/A has absolutely no relevance to this discussion.



I agree, a highway test if done right (as s123nr claims to have) could give you a good idea of what to expect though. I would have to say a controlled dyno environment would be ideal, however.

But from what people say on here and from that article, I'd bet you could expect a 4-7 degree drop on average (on our cars anyway).