Functional Ram Air Hood
1 - 11 of 11 Posts
Joined
·
4,205 Posts
RamAirHood.com as mentioned. It is fiberglass, and functional.
![]()
Joined
·
4,205 Posts
Joined
·
315 Posts
The hood looks great, I wish I had one....
That being said the site makes HUGE claims that are untrue and exaggerated. The site states you can "pressurize" the air box (essentially getting boost) from use of their hoods (at 50 mph no less).
*I dont mean to be a dick about my upcoming explanations....but I feel there is so much BS about HP and power adders if I can help dispel any myths about products or claims I will.
-While not impossible to gain a small amount of positive pressure with ram air, there are factors that are not taken in account with this system and make their claims impossible.
Correct placement of a 'functional' ram air setup is derived from a HUGE amount of R&D and engineering. It is not simply taking a tube and pointing it forward and getting benefits (*seems so easy...but...it aint), elements of intake size, intake tract length, intake tract taper, air box size, engine displacement, volumetric efficiency, RPM, obtainable speed and HUNDREDS of other factors are needed to be optimized to take advantage of the ram air affect.
![]()
Firstly, you can see from the F150 example there is a CLEAR separation of the air stream over the hood body where the hoods 'ram air' intakes are. This is due to the boundary layer (*this is also subsequently why water droplets sit on your hood at 100 mph) and the air looping over the top of the hood from turbulence after the wetted surface area and the immediate hard angle from grill to hood (wont explain, just trust me). To be functional you would need to have the intake ABOVE this separation area. (This is why you will see the intercooler intakes on the WRX STi sitting a ridiculous 8" off and aft the hood).
To have a truly functional ram air intake, you must first determine where the highest pressure area is on the tundra (or any vehicle) is. This is often located at the base of the windshield, and many people have ironically found they have achieved higher HP levels by turning their ram air intakes backwards and point them at the base of the windshield. (this can also be supported with the F150 pic). (*also another high pressure area is located low and in the middle of the front bumper.)
Once the high pressure area is located you would then need to determine the correct size of the air scoop for the engine and obtainable speed.
The Mayfield Company Homepage - Automotive Analyses
After this you must make an intake tract, with correct taper to an airbox designed with H. Helmholtz principles.
(If done, I could see a 15% HP increase over OEM possible, and WHY the (in box) CAI makes more HP over a filter on a tube) [if flow is not a factor], and why cutting holes or adding tubes to OEM airboxes wont always add HP and can often times loose HP even though they sound louder. (*let the shout'en begin!!!)
-Again its possible to go positive numbers with ram air.....I am making almost 1.3 psi @ 210 mph.
I think the hood looks great (and would put one on my truck)....but its site claims more HP and MPG....and I personally believe its very possible to loose HP by their choice in placement.
-Sorry for the long post.....
~JH
That being said the site makes HUGE claims that are untrue and exaggerated. The site states you can "pressurize" the air box (essentially getting boost) from use of their hoods (at 50 mph no less).
*I dont mean to be a dick about my upcoming explanations....but I feel there is so much BS about HP and power adders if I can help dispel any myths about products or claims I will.
-While not impossible to gain a small amount of positive pressure with ram air, there are factors that are not taken in account with this system and make their claims impossible.
Correct placement of a 'functional' ram air setup is derived from a HUGE amount of R&D and engineering. It is not simply taking a tube and pointing it forward and getting benefits (*seems so easy...but...it aint), elements of intake size, intake tract length, intake tract taper, air box size, engine displacement, volumetric efficiency, RPM, obtainable speed and HUNDREDS of other factors are needed to be optimized to take advantage of the ram air affect.
Firstly, you can see from the F150 example there is a CLEAR separation of the air stream over the hood body where the hoods 'ram air' intakes are. This is due to the boundary layer (*this is also subsequently why water droplets sit on your hood at 100 mph) and the air looping over the top of the hood from turbulence after the wetted surface area and the immediate hard angle from grill to hood (wont explain, just trust me). To be functional you would need to have the intake ABOVE this separation area. (This is why you will see the intercooler intakes on the WRX STi sitting a ridiculous 8" off and aft the hood).
To have a truly functional ram air intake, you must first determine where the highest pressure area is on the tundra (or any vehicle) is. This is often located at the base of the windshield, and many people have ironically found they have achieved higher HP levels by turning their ram air intakes backwards and point them at the base of the windshield. (this can also be supported with the F150 pic). (*also another high pressure area is located low and in the middle of the front bumper.)
Once the high pressure area is located you would then need to determine the correct size of the air scoop for the engine and obtainable speed.
The Mayfield Company Homepage - Automotive Analyses
After this you must make an intake tract, with correct taper to an airbox designed with H. Helmholtz principles.
(If done, I could see a 15% HP increase over OEM possible, and WHY the (in box) CAI makes more HP over a filter on a tube) [if flow is not a factor], and why cutting holes or adding tubes to OEM airboxes wont always add HP and can often times loose HP even though they sound louder. (*let the shout'en begin!!!)
-Again its possible to go positive numbers with ram air.....I am making almost 1.3 psi @ 210 mph.
I think the hood looks great (and would put one on my truck)....but its site claims more HP and MPG....and I personally believe its very possible to loose HP by their choice in placement.
-Sorry for the long post.....
~JH
Joined
·
4,205 Posts
You have to go over 150MPH to gain anything from a RamAir Hood. While it does make for a mean growl coupled with an intake and my exhaust, it is just for cosmetics as with any RamAir Hood whether factory or not. But it is functional, just not to maybe what most people might think.
Joined
·
1,171 Posts
Good read for those interested...
![]()
Joined
·
736 Posts
thanks for that info...
Joined
·
297 Posts
Points sent. Awesome post :tu:
1 - 11 of 11 Posts
