hood popped
#21
Boost Pope
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Cutting a well placed vent in the hood decreases the air pressure behind the radiator.
The net effect of either is to increase the pressure differential across the radiator, and that's what leads to increased airflow through the radiator.
#23
Alright, home from work and reading all these posts. I think the question was a legitimate one and i'm sure i'm not the only one to ever ponder the idea?
I will admit that the idea came to me shortly after a few bong hits while out in the garage but nevertheless.
To stoke the fire...since the front bumper is basically a half moon shape wouldn't air still be directed downward and into the radiator while also upward and under the popped hood? And to add gasoline...perhaps the incoming air entering the popped hood and forcing air down and out of the engine compartment may create a venturi effect on the air entering the radiator and help to suck even more air in?
Awaiting my beating.
I will admit that the idea came to me shortly after a few bong hits while out in the garage but nevertheless.
To stoke the fire...since the front bumper is basically a half moon shape wouldn't air still be directed downward and into the radiator while also upward and under the popped hood? And to add gasoline...perhaps the incoming air entering the popped hood and forcing air down and out of the engine compartment may create a venturi effect on the air entering the radiator and help to suck even more air in?
Awaiting my beating.
#24
To stoke the fire...since the front bumper is basically a half moon shape wouldn't air still be directed downward and into the radiator while also upward and under the popped hood? And to add gasoline...perhaps the incoming air entering the popped hood and forcing air down and out of the engine compartment may create a venturi effect on the air entering the radiator and help to suck even more air in?
Make it more simple. You do not want air under the hood. Is bad. No no.
#26
We used to have to pop the hood on our 84' Ford F-150 when hauling wagons with 300+ square bails (23,000+ pounds at some points). If you didn't, it would overheat. We were also traveling at 15-20mph MAX, so that could have something to do with it. When your traveling at anything above those speeds, as others have said, your better off with it closed.
#30
Man, you guys need to shake the sand out of your vagina's.
I'm not overheating at all but I'm not really making much boost at the moment since I don't have an actuator yet. The wastegate is tied loosely shut, and I'm seeing like 3psi max. Half *** yes, but I'm impatient.
I did see a big difference in the temp of the intake pipe after popping the hood on back to back runs, the second run was almost cool to the touch while the first almost burned me. This was all in 90 degree weather but only at speeds up to about 60.
I realize the engine is not air cooled, hustler. But cool air over the intake pipe, air filter, and turbo can't be a bad thing. I guess I'll be that guy, and keep messing with it and see if I start overheating.
I'm not overheating at all but I'm not really making much boost at the moment since I don't have an actuator yet. The wastegate is tied loosely shut, and I'm seeing like 3psi max. Half *** yes, but I'm impatient.
I did see a big difference in the temp of the intake pipe after popping the hood on back to back runs, the second run was almost cool to the touch while the first almost burned me. This was all in 90 degree weather but only at speeds up to about 60.
I realize the engine is not air cooled, hustler. But cool air over the intake pipe, air filter, and turbo can't be a bad thing. I guess I'll be that guy, and keep messing with it and see if I start overheating.
#31
#32
Tour de Franzia
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Um...the temp of the turbo and piping has nothing to do with water temp. You need to read first, ask questions later. We've already told you and everyone else what to do a few dozen times now. We usually help out the first time you ask, but no one is going to spoon feed you...don't make me thin the herd.
#33
I'm more or less just looking for ways to keep the charge cooler to help avoid knock while my system is not yet intercooled. The intake pipe is setup directly across the hood opening, it literally gets blasted with cool air while driving. Cooler air in, cooler air out, cooler engine overall.
You would think that the amount of air that would be rushing past the engine, would minimize the negative effects of having less positive pressure at the radiator mouth. Since the turbo is water cooled as well, keeping the turbo cooler would help to pull heat from the coolant.
I mean were talking about less than 2in of an opening with the hood popped. It's not like i'm racing around with the hood off.
You would think that the amount of air that would be rushing past the engine, would minimize the negative effects of having less positive pressure at the radiator mouth. Since the turbo is water cooled as well, keeping the turbo cooler would help to pull heat from the coolant.
I mean were talking about less than 2in of an opening with the hood popped. It's not like i'm racing around with the hood off.
#34
Tour de Franzia
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I can't do hide the conspiracy any longer, you caught us...popping the hood is the "secret intercooler" that we've been using to make so much power and lower water temps. I must admit that I stole the idea from McLaren F1.
#37
I'm more or less just looking for ways to keep the charge cooler to help avoid knock while my system is not yet intercooled. The intake pipe is setup directly across the hood opening, it literally gets blasted with cool air while driving. Cooler air in, cooler air out, cooler engine overall.
You would think that the amount of air that would be rushing past the engine, would minimize the negative effects of having less positive pressure at the radiator mouth. Since the turbo is water cooled as well, keeping the turbo cooler would help to pull heat from the coolant.
I mean were talking about less than 2in of an opening with the hood popped. It's not like i'm racing around with the hood off.
You would think that the amount of air that would be rushing past the engine, would minimize the negative effects of having less positive pressure at the radiator mouth. Since the turbo is water cooled as well, keeping the turbo cooler would help to pull heat from the coolant.
I mean were talking about less than 2in of an opening with the hood popped. It's not like i'm racing around with the hood off.
#39
Pop the hood. While youre at it, another trick to lower compression and cool everything down at the same time us jb welding pennies to the top if your pistons. Ask joe perez. He can further edjucate you on this
#40
another hour of comparison-
Took it out today along with my digital pyrometer and did some before/after testing with the same route and time frame. Temp outside is sunny and around 85F and running a rich tune of around 10.5-11.00to1, max boost 3-4psi. Timing retarded by 1-3 degrees from 3k-7k and i'm not hearing any knock either way.
Testing after first run with hood closed-
Temp at filter-131f
temp at last bend before TB-155f
temp at turbine-660f
temp at compressor 138f
Testing after second run with hood popped and safety wired-
at filter 113f
at last bend-134f
at turbine-630f
at compressor-122f
I never went over 60mph and my water temp gauge never went past half.
IDK? It seems to work at least a lower speeds, kinda afraid to go any faster with the hood up.
Are you guys seeing temps in the 750's at the collector on the log manifolds? Not used to that.
Took it out today along with my digital pyrometer and did some before/after testing with the same route and time frame. Temp outside is sunny and around 85F and running a rich tune of around 10.5-11.00to1, max boost 3-4psi. Timing retarded by 1-3 degrees from 3k-7k and i'm not hearing any knock either way.
Testing after first run with hood closed-
Temp at filter-131f
temp at last bend before TB-155f
temp at turbine-660f
temp at compressor 138f
Testing after second run with hood popped and safety wired-
at filter 113f
at last bend-134f
at turbine-630f
at compressor-122f
I never went over 60mph and my water temp gauge never went past half.
IDK? It seems to work at least a lower speeds, kinda afraid to go any faster with the hood up.
Are you guys seeing temps in the 750's at the collector on the log manifolds? Not used to that.
Last edited by flounder; 07-17-2010 at 12:08 PM.