Hood spacers, gave it a try.

[bigbrowndog]

It would get you a defect notice in Queensland.That or add on rear facing scoops as if a hose bursts your vision will be obscured.It must also be letting engine fumes down the airvent .cheers

 

[SUMOTOY]

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.

Exactly. For more on this read Toys R Us report on removing the headlight to increase pressure in the air inlet. My suspicion why that didn't work is the same concept, high pressure air offset by engine bay high pressure air trying to get out.

Cowl induction can work, but usually it's not used for any type of airflow for cooling. It is used for intake air, and some intercoolers installs.

Hood vents can be placed in low pressure zones at speed. This gives good heat release at all speeds. Raising the hood only addresses low speed IMO. There is a lot of pressure in your HVAC from cowl induction, try turning the fan off, by 25mph it exceeds low speed fan velocity.

SJ

 

[alkaline747trio]

I'll do the yarn trick, and then I'll check my coolant temps, if it's negative then all in good testing, if positive then this is a good cheap mod.

 

[Jason Andrews]

747, have you tried the yarn trick yet at highway speeds? I dont have anything that is similar to test.

It might be working too well for me. I am now worried, with the cold weather on its way, this mod may effect time to reach normal operating conditions. (Supposed to snow here tonight)

The fan pushes the air to the back and it vents right out Not so great for warming up a cold truck in the winter. It is taking a little longer than I would like to heat up.

But my rig is taking 6-7 minutes after starting and driving to reach mid level. Didn't used to do that.

I think some vents from the quarter panel of a 60/62 would work great, or the very rear of the 100 series. IIRC, the quarter panel is a low pressure area. Everything new from BMW's, to Escalades, Tahoe?, to Range Rover's all have a passive heat venting solution like this on them. Look around and see.

 

[trojan_knight]

i removed the rubber and did about 1/2 inch spacers and noticed a significant air temperature drop on top of the head. with no spacers it was 220-250 degrees F all the time. now it is 120-160 around town and 100 or less on the highway.

 

[FirstToy]

I think the GM products have vents for style only- non-functional. I didn't notice any vents on the BMW suv's...? They do have that big one across the hood like Mercedes sedans don't they?

RR has that big vertical one (2 strips of contrasting color). Is that functional or just looks?

I posted a pic of a Jeep hood that used 100 series rear vents in another thread. turned out ok-nice.

I would close down the hood in super cold weather. I remember back in Indiana, people would put a piece of cardboard over the grille on severe days so the engine could warm up and stay warm.

 

[hks3sgte]

That's old school!

 

[Jason Andrews]

I think the GM products have vents for style only- non-functional. I didn't notice any vents on the BMW suv's...? They do have that big one across the hood like Mercedes sedans don't they?

RR has that big vertical one (2 strips of contrasting color). Is that functional or just looks?

If its for looks I just have to say that is so poser ghey. The BMW ones I was reffering to are on the small convertable they are the stlye of the ones on the quarter panel and hood of FJ40's.

Yeah, the RR has one that I thought Looked real, similar to the front hood of an h2. Wonder if those are just for looks also? humm?

Yea, thanks for the suggestion. Better unspace the hood!

 

[alkaline747trio]

Got some spacer'd numbers.

My quage reads between 160 and 180* max of 190 after shutting down the engine w/ ambient being 70*.

It will fluctuate many times from 160-180 with about a 20 second pause at 160*, and an 8-10 second pause at 180*, taking less than 50 seconds to go from 160-180 and less than 30 from 180-160.

I'm assuming this is the thermostat opening and closing. If this is the case, ambient being 70*, no heat or AC, my cooling system is working very well.

I will remove the spacers next week and return back with those numbers and numbers from this weekend's Uwharrie trip. I only wish I could have had the quage installed durring the warmer months to see how my truck operates in 100* weather w/ AC on.

 

[CreeperSleeper]

747, did you run longer bolts for this? do you remember how long they were and what the thread pitch was? TIA

 

[SteveH]

Couple observations - with spacers, now the hood fits about as well as the hood on the average 1973-87 GM pickup .

Also, recall all the original VW Beetles with the mod to allow the top of the hood (at the rear) to stand 6" away from the vehicle. This hood lift is tame in comparison. Also, you could remove all the spacers all winter long in a colder climate, so it would only look this way during June/July/August, unless you live in a terminally hot climate.

It would be slick to make a labyrinth gasket that would stop rainwater from cascading down the firewall (when parked) but would allow the hot air to escape from the back of the engine compartment while driving.

 

[arbetrader]

just remove your fenderwells

 

[elhombre]

To add another bit of evidence that this doesn't work like one would think is to look at most all the new cars and pick-up trucks with the plastic air-dam hanging down in front. These increase the pressure in front of the plastic air-dam and inversly cause a reduction in pressure on the engine side of the air-dam. This causes the air to move into radiator at a higher pressure (volume) and the reduction side actually draws it into the engine compartment, thus moving more air through the radiator.

Picking the hood up would reduce the temperature under the hood because it removes the air that was heated up by convection. But this is done at the expense of less air moving through the radiator at speed.

If you want to reduce hood temperatures, tack/ glue on some aluminumized radiate barrier on the under side of the hood.

 

[alkaline747trio]

This mod does work, as an escape for air at low speeds and as ram air at higher speeds. The ram air doesn't work against the grain like you would think and overall temps are lower, 185º max 3000rpms 70mph max a/c hoodspacers, 195º+ is common without them, trail speed temp difference is even greater, about 210º a/c on without spacers, 190º with spacers.

 

[re_guderian]

This mod does work, as an escape for air at low speeds and as ram air at higher speeds. The ram air doesn't work against the grain like you would think and overall temps are lower, 185º max 3000rpms 70mph max a/c hoodspacers, 195º+ is common without them, trail speed temp difference is even greater, about 210º a/c on without spacers, 190º with spacers.

Are you quoting coolant temps, or underhood ambient temps?


edit - > never mind, I see upon re-reading you are talking about coolant temps.

 

[alkaline747trio]

Coolant, this is with a mechanical gauge with sender in the upper radiator hose.

 

[mason]

Would removing the fender skirts allow more heat to pass through the compartment? I know mine hasn't ever overheated, but the center console is always warm to the touch.

-Eddie

 

[CreeperSleeper]

Coolant, this is with a mechanical gauge with sender in the upper radiator hose.

Yeah, but what hardware did you use!!!

 

[alkaline747trio]

What do you mean creeper?

 

[CreeperSleeper]

747, did you run longer bolts for this? do you remember how long they were and what the thread pitch was? TIA

This is what I mean...