An idea for added airflow in 1FZ engine

[Romer]

I just went out and sipping a beer had an idea on increasing airflow, supercharger or not. More airflow is good no matter what you are running.

The 2nd battery tray is blocking air flow. The radiator overflow blocked some before the tray was there. I do notice it being hotter in the engine bay.

So, here is what I am thinking:
1) Move the Radiator overflow to the drivers side in front of the primary battery. Lots of room to do this.
2) Trim the battery tray so that it is only 7" from the fender to the end. Still need to figure the best way to do this and provide the protection of the tray.
3) Turn the battery 90 deg up against the Fender. Build a mount to hold it in place.

This will open up a clear path of 4 inches across for airflow from the fender well to the hood around the pass side of the radiator. I think this is more than before the 2nd tray was installed due to the overflow bottle. In fact, the 2nd battery now won't be blocking any additional airflow based on the airfilter being next in line. The new location of the overflow won't be block any additional flow due to the primary battery tray. I have a Yellow Top in the Primary tray and there is lots of room there.

Again, this for any application, stock engine, TRD or Supercharger.

I also think wrapping the exhaust is a good idea.


Thoughts?

 

[LX_TREME]

No scoop? here's mine added airflow into 1FZ and psstt...Slee Turbo soon

 

[nakman]

I like the thought, but it's going to be tricky to slide the battery tray over. Remember how those mounting points are all at different elevations on the bottom, would take a while to get it secure again. Someone posted the idea of just removing the gasket at the back of the engine hood on another post not too long ago, which allows more hot air to exit the engine bay. To me that makes a lot of sense, and comes with an easy "undo" if you change your mind.

Why are you worried about under hood temps? Or are you trying to shove more air through your filter.. don't make it too cool in there or the corn dogs won't get done.

 

[landtank]

No scoop? here's mine added airflow into 1FZ and psstt...Slee Turbo soon

I know you are very fond of this scoop, but I think it's counter productive. What we're looking for is an exhaust for the engine compartment and that scoop would pressurize it, the opposite of what we're looking for.

 

[Rusty Phillips]

re: cutting the hood to put scoops or louvers

did a lot of thinking during a long road trip this past weekend staring at my manifold vacuum gauge..... wondering just what point to cut a hole in my hood

we need to rig up a low vacuum (inches of water not inches mercury like my manifold) gauge to tubing & position the end of the tube at various points along the hood to see where the air pressure is negative and where it goes positive....... ideally I would run cord from the front of the tube forward to my brush guard (and back to the cabin) & thus be able to move the tube back and forth while trucking down the road

think cowl induction scoops - too far back on the hood close to the windshield and you are positive

but up close to the nose and (bernouli principle) you will get a slight negative

I really think just a simple cutout towards the front of the hood would suffice with some sort of grill to keep stuff from falling in the engine compartment (- ok - the grill is really to put corn dogs or foil wrapped burritos on)]

another project for another day

 

[Romer]

I like the thought, but it's going to be tricky to slide the battery tray over. Remember how those mounting points are all at different elevations on the bottom, would take a while to get it secure again. .

I would not change any of the mounting holes and trim it right were it is. Either the side to wards the engine will be exposed or I will figure out how to take what I trimmed off and cover the side. Lots of trucks have the battery exposed in the engine bay, but my goal would be to work something up with the trimmings

This just seems easy simple and almost Free! I am going to try it this weekend, I'll take pics. I don't have a temp sensor, so I will not have any before and after temps other than feel. I know when I open the hood now, it feels hotter than before I had my dual battery.

Anyone know what size of hose I need to get for the overflow? Will need to extend the hose a bit so it won't kink going to the other side.

 

[MaddBaggins]

You know, if you succeed in your mod and remove the seal on the back of the hood, you could get some good flow-thru in there.

 

[fzj80kidpen]

Interesting,
Romer - if you get 4" of opening there then you have succeeded.
LX_TREME - I drove for 3 hours with a small stick in the middle of hood at 75mph. It finally blew off only when a big semi passed me and the cross wind blew it off. My point being that I would bet you that you hood scoop is actually doing the complete opposite of what you may think. I bet that hot air is blowing out that vent/scoop even with that filter sucking air right under it.
As for 2nd battery placement, if it were me I would put it up under the driver next to the transfer. Plenty of room there or up under the back spare tire cavity.

 

[SUMOTOY]

I know you are very fond of this scoop, but I think it's counter productive. What we're looking for is an exhaust for the engine compartment and that scoop would pressurize it, the opposite of what we're looking for.

completely agree. Ducting air to a cone filter is pretty easy without using hood scoop. Adding more air pressure to the engine bay reduces the cooling efficiency of the radiator, and traps more of the airflow.

Take that scoop and turn it around, I'd bet you'd see a performance gain.

Scott Justusson

 

[SUMOTOY]

re: cutting the hood to put scoops or louvers

did a lot of thinking during a long road trip this past weekend staring at my manifold vacuum gauge..... wondering just what point to cut a hole in my hood

we need to rig up a low vacuum (inches of water not inches mercury like my manifold) gauge to tubing & position the end of the tube at various points along the hood to see where the air pressure is negative and where it goes positive....... ideally I would run cord from the front of the tube forward to my brush guard (and back to the cabin) & thus be able to move the tube back and forth while trucking down the road

think cowl induction scoops - too far back on the hood close to the windshield and you are positive



but up close to the nose and (bernouli principle) you will get a slight negative

I really think just a simple cutout towards the front of the hood would suffice with some sort of grill to keep stuff from falling in the engine compartment (- ok - the grill is really to put corn dogs or foil wrapped burritos on)]

another project for another day

A lot of testing on track cars, I've found that the best low pressure zone with highest trapped heat is about 6in in front of the windshield at the back quarters of the hood. Any vents before the radiator will be positive presssure. In fact there is a lot of positive (or zero) pressure about 1/3 back from the front of the hood.

A properly designed hood vent system, should be mounted to the sides of the hood (to the outside of the raised portion). You should also always allow a vent for the exhaust system (exhaust manifold), the heat that thing generates is unreal. Vents into the wheel well are good alternatives to slicing hoods, but are less effective at lower speeds. Spinning wheels are great low pressure zones.

I posted a great technical writeup from some jeep guy several months ago during this whole hood vent discussion. The guy put 50 some temp sensors under his hood, and confirmed that the outside rear quarters of the hood is the best place to get heat out.

Make sure you are doing the right thing to get what you want. Most race cars are great places to look for ideas on venting.

Scott Justusson

 

[Romer]

Is there some cheap and easy to use temp snesor I can get at Checker or Pepboys? I could put the sensor on the air can to get before and after temps.

edit: I see some stuff at Harbor Frieght. I'll drop by there at lunch and the auto parts store.

 

[MDarius]

...3) Turn the battery 90 deg up against the Fender. Build a mount to hold it in place...

The plates in the battery require fluid for the electrons to flow correctly. I don't know much about gel batteries, but I would think this wouldn't be good for a regular battery. As they discharge the fluids cooks off and you end up with an air pocket. With it at the top, no big deal (to some extent). On the side, an entire plate or set of plates would not be covered.

Can anybody confirm/or deny this theory? Feel free to educate me.

 

[SWCruiser]

Questions

Scott,
Great info. On lxtremes vent- isn't that also a potential issue with dust (not on his particular truck , but generally speaking ).

I have another question- It seems venting in the opposite direction would allow for better venting of air flowing through the radiator but doesn't the absence of hood vents also control movement of dust from carrying up into the engine as the air must flow downward?

 

[gnx7]

Here is a basic mod I do on my road race cars: remove the rubber seal attached to the back of the firewall that seals to the hood. Great way to let air escape. It will work better at speed.

 

[Romer]

The plates in the battery require fluid for the electrons to flow correctly. I don't know much about gel batteries, but I would think this wouldn't be good for a regular battery. As they discharge the fluids cooks off and you end up with an air pocket. With it at the top, no big deal (to some extent). On the side, an entire plate or set of plates would not be covered.

Can anybody confirm/or deny this theory? Feel free to educate me.

Thats not the 90 deg I am talking about. The cables would still be on top. Here is a pic of someone elses engine bay to illustrate

 

[MaddBaggins]

Sealed batteries, like the Optima can be mounted in any position.

 

[Tools R Us]

Is there some cheap and easy to use temp snesor I can get at Checker or Pepboys? I could put the sensor on the air can to get before and after temps.

edit: I see some stuff at Harbor Frieght. I'll drop by there at lunch and the auto parts store.

I am using weather stations from wally world and Fry's. The plain ones only go to 120F, some are available with a wired probe that is made to go in soil, pool, etc that goes to 150-170F. They cost from $5-$15 depending on wireless or wired, with or without the probe.

 

[FirstToy]

This is the informative website of a jeep owner and lessons in hood venting
http://www.oman4x4.com/hoodvents.htm

 

[bigbrowndog]

Nissan seems to think the scoops are ok , also the Pajero from Mitsubishi wears them.It looks to me like the cold air is going in to the intercooler on the patrol for cooling not letting it out.

 

[cpg]

I would mount the second battery under the driver area. Plenty of room, short cable to starter, weight lower. Better air circulation in engine bay.