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The plastic intake ram air box running across the top of the radiator becomes uncomfortably hot to the touch...because it's dual purpose as air intake and 4th side of ductig atop a 185 degree radiator.
Engine components beneath airbox, the water inlet/thermostat housing, radiator hoses could be insulated to reduce intake charge temperature therby increasing power.
Interested in receiving input on engineered solutions for materials and applications
This chart courtesy of David Vizard.
My conservative estimate is temperature reduction of 40 Degrees F....about 4% torque increase through insulating intake conduit to throttle body... Ram air box sits astride radiator.. Ram air box removed depicts 185 degree F: Radiator, Water inlet housing (mine is from an LS430) ,; upper radiator hose..all export heat into intake stream.(Aftermarket hose came with car....will replace) Bottom image of plastic ram air box...adequate room for a thin sheet of composite insulation...however aluminum foil composite material will require barrier that will not react (dissimilar metal corrosion) with metal radiator support.
Will contact DESIGN ENGINEERING INC for recommendations and report.
I think more than a ram air which yeah it does, it is the first part of the induction silencer system. And yes not good for the performance minded. Also remove the plastic cover on top of the engine, and get rid of the heat conduction aluminum intake manifold. The plastic cover helps make it an oven for that manifold.
people in the past have removed the pass side headlight gasket to route air directly into the intake box. I think JBrady was the originator of this idea.
get rid of the heat conduction aluminum intake manifold
And replace it with?
A nice printed plastic job of course. Al conducts and holds the heat then transfers it to the air flowing into the engine and is why some folks like in the F1 crowd use carbon fiber induction systems. So if someone is really concerned about thermal management for increased power that is an important contribution. Also any effort that can be made to enhance cooling around the top of the engine, maybe air scoops in the hood etc.
The plastic intake ram air box running across the top of the radiator becomes uncomfortably hot to the touch...because it's dual purpose as air intake and 4th side of ductig atop a 185 degree radiator.
Engine components beneath airbox, the water inlet/thermostat housing, radiator hoses could be insulated to reduce intake charge temperature therby increasing power.
Interested in receiving input on engineered solutions for materials and applications
This chart courtesy of David Vizard.
My conservative estimate is temperature reduction of 40 Degrees F....about 4% torque increase through insulating intake conduit to throttle body... Ram air box sits astride radiator.. Ram air box removed depicts 185 degree F: Radiator, Water inlet housing (mine is from an LS430) ,; upper radiator hose..all export heat into intake stream.(Aftermarket hose came with car....will replace) Bottom image of plastic ram air box...adequate room for a thin sheet of composite insulation...however aluminum foil composite material will require barrier that will not react (dissimilar metal corrosion) with metal radiator support.
Will contact DESIGN ENGINEERING INC for recommendations and report.
http://www.designengineering.com
DEI suggests SKU: 050501 3/16" thick aluminium faced-insulating composite with high temperature pressure sensitive adhesive
I wonder how much heat the is picked up by the air before it reaches the afm housing. I dont think we would gain any noticeable power, but cold air is always better
I wonder how much heat the is picked up by the air before it reaches the afm housing. I dont think we would gain any noticeable power, but cold air is always better
So David Vizard's temperature chart provides achieved temperature reduction vs % of power increase..
The plastic ram air box (spanning atop radiator) is hot to touch-and that is with ambient air flowing through it.
The raim air junctuons with the air filter box is isolated via a foam rubber gasket, so temperature rise is from radiator.
Insulating between the ram air box and radiator suggests reduced temperature of intake charge.
Will take before and after temperature readings of top right and tleft of ram air housing.
So David Vizard's temperature chart provides achieved temperature reduction vs % of power increase..
The plastic ram air box (spanning atop radiator) is hot to touch-and that is with ambient air flowing through it.
The raim air junctuons with the air filter box is isolated via a foam rubber gasket, so temperature rise is from radiator.
Insulating between the ram air box and radiator suggests reduced temperature of intake charge.
Will take before and after temperature readings of top right and tleft of ram air housing.
Acquired Heat & Sound Barrier in 21" X 48" X 3/16" roll from DEI (Design Engineering, Inc.) Performance Products, Part # 050502.
Prepared paper templates, cut material to size and installed heat & sound barrier to the underside of the ram air box that runs across the top of the 185-200 F radiator.
As the material is 3/16" thick, it fit underneath the ram air assembly without clearance issues.
After removing roll from box, allowed it to flatten overnight.before installing. 1st paper template
and second template.. Paper template shown on bottom of ram air assembly...There are three planes on the bottom so am applying material in three sections. Close up showing slits cut in material to prevent puckering of material and facilitate conformity around curves. Material cut to size and ready to remove pressure sensitive adhesive liner for installation. Bottom of ram air assembly after intallation of heat barrier.
Used outdoor rated high temperature foil tape to seal slits and cover any gaps (nominal)
The DEI material incorporates a high temperature, high surface energy adhesive that works well with plastic.
Very satisfied with the results.
The ram air assembly fit without clearance issues..
Notice I worked around the OEM rubber isolation/damping strip..same material thickness as heat barrier.
Will acquire and present temperature readings soon
Acquired Heat & Sound Barrier in 21" X 48" X 3/16" roll from DEI (Design Engineering, Inc.) Performance Products, Part # 050502.
Prepared paper templates, cut material to size and installed heat & sound barrier to the underside of the ram air box that runs across the top of the 185-200 F radiator.
As the material is 3/16" thick, it fit underneath the ram air assembly without clearance issues.
After removing roll from box, allowed it to flatten overnight.before installing. 1st paper template
and second template.. Paper template shown on bottom of ram air assembly...There are three planes on the bottom so am applying material in three sections. Close up showing slits cut in material to prevent puckering of material and facilitate conformity around curves. Material cut to size and ready to remove pressure sensitive adhesive liner for installation. Bottom of ram air assembly after intallation of heat barrier.
Used outdoor rated high temperature foil tape to seal slits and cover any gaps (nominal)
The DEI material incorporates a high temperature, high surface energy adhesive that works well with plastic.
Very satisfied with the results.
The ram air assembly fit without clearance issues..
Notice I worked around the OEM rubber isolation/damping strip..same material thickness as heat barrier.
Will acquire and present temperature readings soon
While the ram air intake assembly is much cooler, the resonator air intake assembly attaching to the throttle body is very hot.
It runs atop.the 200 F water crossover and near thr upper radiator hose.
Insulating the front (and rear) water crossover should reduce temperature of intake airm
Insulating the upper radiator hose should reduce heat imparted on intake system Front crossover shown below inlet of where throttle body resides Front and rear water crossovers depicted...200 F coolant
While the ram air intake assembly is much cooler, the resonator air intake assembly attaching to the throttle body is very hot.
It runs atop.the 200 F water crossover and near thr upper radiator hose.
Insulating the front (and rear) water crossover should reduce temperature of intake airm
Insulating the upper radiator hose should reduce heat imparted on intake system Front crossover shown below inlet of where throttle body resides Front and rear water crossovers depicted...200 F coolant
1998 Lexus LS400 incorporated ACIS manifold to improve engine performance across the power curve.
A new heat barrier inake manifold gasket sandwiched resin in between two metal.gaakets...thereby reducing heat transfer from cylinder head to intake manifold.
However, Totota did not put the ribbon on the package.
The relatively enclosed area of the engine valley(where starter resides) reaches engine operating temperature of 185-200 F.....and has little if any ventilation, so as heat rises it is absorbed into bottom surface area of intake manifold...and dispersed into the manifold.
The intake manifold top area (visible through engine cover) is uncomfortably hot to the touch..
To remedy this problem and increase power across the curve (reduced temperature of intake charge increases power) , a thermal barrier applied underside the intake to shield it from engine heat..
Some images;
This image depicts the heat barrier intake manifold gasket used on 1998 LS400. .. Bottom view of ACIS intake manifold...while Lexus thermally isolated the intake manifold from the head at the ports with the new gasket design, it seemingly ignored the rest of the underside of the intake....
Both coolant crossover pipes run in close proximity tmparting heat.into intake DEI Performane Products offers a thermal barrier that will block heat absorption ithrough bottom of intake manifold..
This is identical material used underside of plastic ram air assembly shown earlier in this post.....it is not yet tailored but presents the general concept . Contemplating whether to fill the underside pockets of intake with expanding foam for further heat isolation. Upper half of ACIS manifold..
Another area that merits attention is the steel.gasket between upper and lower half of intake. Toyota determined that a non metallic gasket would reduce heat transfer between cylinder head to intake, but elected to not thermally isolate upper and lower half of intake manifold. Perhaps due to thickness and tolerance considerations. Anyone with suggestions here??.Spray coating thermal barrier compatible between Aluminum and steel??
Otherwise , suggestions on a thin yet durable non-metallic gasket material.
1998-2000 LS400 the plastic intake air connector pipe and intake silencer assembly runs across the hot thermostat housing/inlet assembly and is downwind from the radiator fan..
It is hot to touch at normal engine operating temperature with intake air running through it suggesting it is absorbing heat from the coolant crossover , thermostat housing assembly and radiator airstream.
Time to insulate....
Image depicts the molding seam between the upper and lower half of the intake tube assembly. I will insulate the lower half below this line. Bottom view of intake connector tube/resonator assembly Preparing paper template...necessary as there are numerous compound curves. Template on DEI Thermal barrier material. DEI thermal barrier composite after pattern cut. DEI thermal barrier shown from adhesive side depicting slits allowing material to lay flat over compound curves without puckering. Beginning of application of DEI thermal barrier to underside half of air intake connector tube. In process....a few slim triangular slivers are removed from inner curve of intake tube so material is not lumpen. Topside image of air intak connector tube..
Attempting to retain the overall black look of engine compartment by insulating bottom side only. Per DEI, the material can be painted black in lower temperature applications. (this qualifies) Intake connector tube assembly reinstalled.
The silver thermal insulating material is not too visible up top.. Will see if insulating only bottom half (closest to hot engine) provides results...However the hot radiator airstream flows over topside, so should it become necessary will insulate top half and paint black.
1998-2000 LS400 the plastic intake air connector pipe and intake silencer assembly runs across the hot thermostat housing/inlet assembly and is downwind from the radiator fan..
It is hot to touch at normal engine operating temperature with intake air running through it suggesting it is absorbing heat from the coolant crossover , thermostat housing assembly and radiator airstream.
Time to insulate....
Image depicts the molding seam between the upper and lower half of the intake tube assembly. I will insulate the lower half below this line. Bottom view of intake connector tube/resonator assembly Preparing paper template...necessary as there are numerous compound curves. Template on DEI Thermal barrier material. DEI thermal barrier composite after pattern cut. DEI thermal barrier shown from adhesive side depicting slits allowing material to lay flat over compound curves without puckering. Beginning of application of DEI thermal barrier to underside half of air intake connector tube. In process....a few slim triangular slivers are removed from inner curve of intake tube so material is not lumpen. Topside image of air intak connector tube..
Attempting to retain the overall black look of engine compartment by insulating bottom side only. Per DEI, the material can be painted black in lower temperature applications. (this qualifies) Intake connector tube assembly reinstalled.
The silver thermal insulating material is not too visible up top.. Will see if insulating only bottom half (closest to hot engine) provides results...However the hot radiator airstream flows over topside, so should it become necessary will insulate top half and paint black.
The coolant crossover/thermostat housing (195 - 200 F) is abour 1/4" - 3/8" below the intake manifold and throttle body assembly, with considerable radiant heat soak.
Next project will thermally isolate the water crossover and thermostat assembly..from intake components.
1998 LS400 image depicts intake manifold throttle body inlet with coolant crossover directly below. This is significantly heating the intake and cooking the throttle body (actuator motor and throttle position sensors)
The coolant crossover/thermostat housing (195 - 200 F) is abour 1/4" - 3/8" below the intake manifold and throttle body assembly, with considerable radiant heat soak.
Next project will thermally isolate the water crossover and thermostat assembly..from intake components.
1998 LS400 image depicts intake manifold throttle body inlet with coolant crossover directly below. This is significantly heating the intake and cooking the throttle body (actuator motor and throttle position sensors)
Air density vs. temperature chart and some supporting physics
Screenshot of physics of horsepower increase in relationship to increased air density (works from absolute zero)
09-24-17, 12:12 PM
Thermal management for increased power
