For the past month or so I have been working on trying to lower the air intake temperature for the carburetor intake in my stock 82 FJ45 for the brutal summer temperatures that are just starting.
I used a turbo remote temperature analyzer that I use on checking aircraft turbo’s and other things. Pretty handy device for this check.
I installed the remote sender at the inlet of my air horn on the air filter housing to see what kind of temps were under the hood while stopped and while driving at different speeds.
Without a doubt I was not surprised on the outcome.
When stopped at a light after 20 minutes of driving - at idle with an OAT (our side air temp) of 85 deg the analyzer read 132 deg of hot air entering the air cleaner’s inlet horn. While driving at around 45 MPH the reading from ram air into the stock engine compartment was 97 deg a 35 deg difference. At a higher speed the reading was 95 deg with same OAT. While in four wheel drive and in LOW the temp was up around close to 200 deg. So I had to find a cold air intake device other than a snorkel.
A snorkel is mainly just for crossing deep water and needs a cretin amount of ram airspeed to travel the length of the tube to the carbs inbox to make some difference in temp in the summer. At low off road speeds on dry land pretty much just helps with any dust but still susceptible and so far I have had no need for a snorkel, maybe one day.
I needed close forced cool air. So what I am about to contribute to my fellow 45 and 40 owners is my attempt to beat the heat. For what its worth.
With my finding for my rig, the closer the better for a cold intake set up. My engine air filter housing inlet horn is pretty much right up front but not enough cold air entering due mostly the radiator sets just to the right side of the intake horn blocking or causing a vortex of incoming ram air.
Step one - need to be close to the housing inlet horn, so cut a 3 1/8” hole at the lower part of the left fender skirt.
Step two - cleaned up the edge of the hole and installed edging trim around the inside of the hole.
Step three - found 3” x 3’ round flex tube.
Step four - cut a 2.5” x 3” section of exhaust tube I had left over form my Ford Bronco days. Used as a splicer section between tube and tube inlet.
Step five - I had a aircraft 3” instrument mount that I converted to the tube inlet holder.
Step six - used two 3.25” hose clamps for tube.
Step seven - install as seen. Temporally pushed the end of the 3” tube into the air filter
housing horn until I can fix it were can be disconnected/installed with some ease .
Grant you to everything good there is a bad, I just have to work around the bad.
The good - The cold/warm ram air inlet seems to be in a good spot for ram air.
Tested at 94 degs OAT- at light, stopped – 76 deg, driving 60 degs. It works.
(I'm sure each FJ is different this is just my findings)
Water from road wheel in a turn has no effect as ingesting water spray “so far”.
Oh yes lots better on the throttle responses, enough to notice.
The bad - Stay ahead or way back of any vehicles on dirt roads as the inlet is bumper high and will ingest dust. I have a cyclone air filter system with a K&N filter so I am not too concerned, yet.
If you cross deep water streams disconnect the system.
On rainy days or winter disconnect. I suspect that carb icing may happen. My tube has a high vertical climb to the inlet so small amounts of water droplets will vaporize before entering the engine.
So there you go something to think about when you’re out off roaming around in the heat or just around town.
Please - comments are truly welcome as maybe I missed something or someone has a better way, that’s what I like about this web site; we are all in it together.
Stay cool.
I used a turbo remote temperature analyzer that I use on checking aircraft turbo’s and other things. Pretty handy device for this check.
I installed the remote sender at the inlet of my air horn on the air filter housing to see what kind of temps were under the hood while stopped and while driving at different speeds.
Without a doubt I was not surprised on the outcome.
When stopped at a light after 20 minutes of driving - at idle with an OAT (our side air temp) of 85 deg the analyzer read 132 deg of hot air entering the air cleaner’s inlet horn. While driving at around 45 MPH the reading from ram air into the stock engine compartment was 97 deg a 35 deg difference. At a higher speed the reading was 95 deg with same OAT. While in four wheel drive and in LOW the temp was up around close to 200 deg. So I had to find a cold air intake device other than a snorkel.
A snorkel is mainly just for crossing deep water and needs a cretin amount of ram airspeed to travel the length of the tube to the carbs inbox to make some difference in temp in the summer. At low off road speeds on dry land pretty much just helps with any dust but still susceptible and so far I have had no need for a snorkel, maybe one day.
I needed close forced cool air. So what I am about to contribute to my fellow 45 and 40 owners is my attempt to beat the heat. For what its worth.
With my finding for my rig, the closer the better for a cold intake set up. My engine air filter housing inlet horn is pretty much right up front but not enough cold air entering due mostly the radiator sets just to the right side of the intake horn blocking or causing a vortex of incoming ram air.
Step one - need to be close to the housing inlet horn, so cut a 3 1/8” hole at the lower part of the left fender skirt.
Step two - cleaned up the edge of the hole and installed edging trim around the inside of the hole.
Step three - found 3” x 3’ round flex tube.
Step four - cut a 2.5” x 3” section of exhaust tube I had left over form my Ford Bronco days. Used as a splicer section between tube and tube inlet.
Step five - I had a aircraft 3” instrument mount that I converted to the tube inlet holder.
Step six - used two 3.25” hose clamps for tube.
Step seven - install as seen. Temporally pushed the end of the 3” tube into the air filter
housing horn until I can fix it were can be disconnected/installed with some ease .
Grant you to everything good there is a bad, I just have to work around the bad.
The good - The cold/warm ram air inlet seems to be in a good spot for ram air.
Tested at 94 degs OAT- at light, stopped – 76 deg, driving 60 degs. It works.
(I'm sure each FJ is different this is just my findings)
Water from road wheel in a turn has no effect as ingesting water spray “so far”.
Oh yes lots better on the throttle responses, enough to notice.
The bad - Stay ahead or way back of any vehicles on dirt roads as the inlet is bumper high and will ingest dust. I have a cyclone air filter system with a K&N filter so I am not too concerned, yet.
If you cross deep water streams disconnect the system.
On rainy days or winter disconnect. I suspect that carb icing may happen. My tube has a high vertical climb to the inlet so small amounts of water droplets will vaporize before entering the engine.
So there you go something to think about when you’re out off roaming around in the heat or just around town.
Please - comments are truly welcome as maybe I missed something or someone has a better way, that’s what I like about this web site; we are all in it together.
Stay cool.
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Hi Kevin, yeah as stated in the initial part of this post I wanted a more direct and a shorter avenue to the air cleaner housing inlet with cooler air. The snorkel at idle only pulls some much air and has a bit of a distance to travel and also needs to be at a speed where the engine is pulling all the air in with the assist of some ram air. My friend with a Jeep has a snorkel installed and it looks cool and it does pull air with the V8 but it travels so far to the air box. We put a piece of toilet paper up to his intake on the snorkel at idle and it barely draws air but for my short run it pulls a bit more than his telling me less travel better draw of air and more. I just finished this install of the outside air cooling tube on this 45 and I must say it really does help. We have had temps in the 98-99 and it is performing much better that sucking the very hot air in the engine compartment especially at idle such as at a stop light as last year in the heat. I properly will install a snorkel at a later date for the river crossings but for now I am only wanting that cooler air for that old 2F beast.
