Hood spacers, gave it a try.

[alkaline747trio]

Well, everyone talks about hood spacers being bad and HVAC problems and "what ifs", so I decided to run with it being the stubborn young gun I am. I am reasonably pleased with the results.

I always thought my truck ran warm, it never overheated according to my needle, but opening the hood it just felt way warmer than anything I have ever driven. That's definately not the case now, I estimate a good 20* drop in average underhood temps. I'll get some numbers once my water temp guage adapter comes in, for more solid results.

Been driving like this for over a month now, and the only problem I have is with the windows down pulling away from a stop I can sometimes catch a whif of "engine smell", same with running fresh air through the vents. No smell at speed, no feelings associated with fumes, passengers haven't commented on it either.

I used a 1" steel spacer and a 1/2" nylon spacer with washers at both ends of the nylon.

Here are some pics, 1" steel spacer, 1/2" nylon spacer, and washers.

 

[CodyRx7]

I don't know if you'd even have to go that high to get significant heat extraction...

You can probably eliminate the "engine smell" in the cab with some of the plastic ventshades that go along the top of the door windows.

 

[airlaird]

Good on ya for trying it out..If I may, aesthetically it looks .. ...waaaay too high Heat will find the smallest area to escape from....there's no need to jack up the hood 2"inches. I almost did it last month with mine...I was going to use a 1" spacer..which was plenty enough. I think it looks like your hood is broken with it that high. I think a little more subtle might do the trick.
airlaird

 

[gbell210]

With it at that height... if you were in a collision, I'd think it would be a hazard. You'd be better off with some reverse hood scoops, and look better as well. But I think this is fine for testing purposes.

Or maybe remove the rubber seal at the back of the hood?

 

[alkaline747trio]

Being just a test, I wasn't too worried about "too high" or looks quite yet. I do plan to try just the 1/2" nylon spacer with the rubber seal removed (only if it can be easily put back on) to see how it looks. After I get some coolant temp numbers I'll give my final thoughts on this, but I figured I'd throw this out there and let people know that the in cab experience isn't nearly as bad as predicted.

 

[airlaird]

Again great job on it..we just thought that was the completed job... I look forward to your results on temps! Did your hood get "skijawed" or out of alignment when you put on all four washers?
airlaird

 

[Jason Andrews]

nice, I have wanted someone to see just how much that helps with some numbers. I have had mine spaced for two months now...it is spaced up about 3/4" which I think is plenty, OR too much IMO.

I have an aux fan infront of the condensor and when I turn it on so much heat flows out it is almost unbelievable. My temp gauge got to the red once and that was scary enuf for me to do some QUICK work! Whew!...I think my 3FE and I got lucky.

No bad smells from the HVAC that I notice.

 

[SUMOTOY]

The biggest issue I see with this mod is that possibly changes from a low pressure release to a cowl induction at speed. For low speed operation, there is no question in my mind it should work. What I suspect happens above say 30mph, this becomes a cowl induction setup. I know when I turn my HVAC fan off and go highway speeds, I have a LOT of high cowl induction pressure. Given the rear of the hood is only another inch or two forward, I would bet it does the same to a raised hood.

Easy to ck, take some yarn and tape it to the trailing edge of the hood. See if it disapears down the engine bay at speed.

Scott Justusson

 

[FirstToy]

alkaline747trio,
thanks for posting the info and pics, very informative.
Please do post some followup after you do your adjustments. your results fall in line w/ my friend w/ a turbo 4Runner- runs w/ a slight gap w/ spacers as you have it.

NYC taxi's pop the hood for summer heat so I'm sure it releases alot of trapped heat...

 

[lowtideride]

Instead of putting spacers on just remove the rubber seal on the cowl...It works the same way but without looking goofy.

 

[airlaird]

confused

[The biggest issue I see with this mod is that possibly changes from a low pressure release to a cowl induction at speed.

Scott, what if it does act like an induction...that will bring in cooler air from outside right?...I don't see how it being a cowl induction being a problem...can you explain for the layman such as I. If it sucks in air ...thats even better..right?
airlaird

 

[alkaline747trio]

FirstToy, I'm on top of that as soon as I can. lowtide, I kinda like the goofy popped look.

 

[lowtideride]

No worry brotha...to each there own.

 

[pulse98]

I don't think we need a hood (maybe except for when it rains). Our aerodynamics can't get any worse

 

[stayalert]

not my cuppa but all this talk reminds me of following my friend to the shop so he could droip of his dad's fiat when I was in highschool....hood popped up...ripped off the fiat, did a couple of cartwheels as we (the fiat and the subaru that we were following the fiat in) drove under it....we both stopped went 2x carried the hood back to the fiat and drove the rest of the way uneventfully.

 

[mot]

I was looking for a way to create more downforce w/o adding a spoiler or anything. This should take care of it. THANKS!

 

[nakman]

[The biggest issue I see with this mod is that possibly changes from a low pressure release to a cowl induction at speed.

Scott, what if it does act like an induction...that will bring in cooler air from outside right?...I don't see how it being a cowl induction being a problem...can you explain for the layman such as I. If it sucks in air ...thats even better..right?
airlaird

I had the exact same thought. So if it releases hot air when going slow and sucks in cool air when going fast that's a win-win. Great idea!

 

[e9999]

good point above, in a frontal collision, wouldn't this hood become a guillotine...?

 

[OZCAL]

I was looking for a way to create more downforce w/o adding a spoiler or anything. This should take care of it. THANKS!

Actually Mot the way it's tilted I think it would cause lift!

 

[Rich]

If air gets pushed into the engine compartment from a high pressure area at the base of the windshield, then the additional pressure in the engine compartment will reduce the airflow through the radiator, reducing the efficiency of the radiator, with a likely increase in engine temperature during high load, high ambient temp conditions. Could adversely affect ac temp, engine temp, and transmission temp.