Vented Hood
06-25-14, 05:05 PM
#26
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George,
I have the same issue and I have a vented hood, my car has the complete Tamon designs front end on it.
It's stacked as such: FMIC, stock oil cooler, stock A/C coil, Koyo rad. It runs plenty cool at sustained speeds but as soon as. I get on the highway and the car gets hot from getting on it good, it stays hot. I think part of it is due to the e-fan I have not turning off and free spinning and highway speed, if I turn the ignition off and coast then cut the car back on it will cool down. Does your e-fan shut off at speed?
I have the same issue and I have a vented hood, my car has the complete Tamon designs front end on it.
It's stacked as such: FMIC, stock oil cooler, stock A/C coil, Koyo rad. It runs plenty cool at sustained speeds but as soon as. I get on the highway and the car gets hot from getting on it good, it stays hot. I think part of it is due to the e-fan I have not turning off and free spinning and highway speed, if I turn the ignition off and coast then cut the car back on it will cool down. Does your e-fan shut off at speed?
I think I'm going to try temporarily wiring a switch into the relay power circuit to cut the fan off on the highway and see how it affects things. If it works I would like to look into figuring out a way to wire the fan relay power into some sort of speed activated switch.
No. I have a GT35R on my 1st gen, but I haven't sold one.
06-25-14, 05:08 PM
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I haven't measured it, but it's artic cold...for about 10 seconds. Then I have to shut it down and turn on the heater and fan full blast to help cool the engine. In 98-degree weather, you can imagine how much fun that is. 
06-25-14, 05:10 PM
#28
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Attila, check John Huijben's build thread, he put a nice hood duct into his 4 rotor FC, he moved the top of the radiator forward to give a bit more room:
https://www.rx7club.com/build-thread...-build-974831/
https://www.rx7club.com/build-thread...-build-974831/
06-25-14, 05:19 PM
#29
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Progress Update
I dropped off the Mitsubishi hood and a spare RX-7 convertible hood at the body shop. The initial reaction from the owner was not positive.
-Both hoods are thin aluminum. Welding would cause lots of deformation.
-There are a lot of struts and braces to be dealt with.
I suggested that we could join the two with certain adhesives. The owner was happier with that approach. At this point, he is going to sit down with a tape measure and some drawing paper to see how the various pieces would line up. Worst case scenario: The total cost of the job would be prohibitive.
-Both hoods are thin aluminum. Welding would cause lots of deformation.
-There are a lot of struts and braces to be dealt with.
I suggested that we could join the two with certain adhesives. The owner was happier with that approach. At this point, he is going to sit down with a tape measure and some drawing paper to see how the various pieces would line up. Worst case scenario: The total cost of the job would be prohibitive.
06-25-14, 06:59 PM
#31
George,
I have the same issue and I have a vented hood, my car has the complete Tamon designs front end on it.
It's stacked as such: FMIC, stock oil cooler, stock A/C coil, Koyo rad. It runs plenty cool at sustained speeds but as soon as. I get on the highway and the car gets hot from getting on it good, it stays hot. I think part of it is due to the e-fan I have not turning off and free spinning and highway speed, if I turn the ignition off and coast then cut the car back on it will cool down. Does your e-fan shut off at speed?
I think I'm going to try temporarily wiring a switch into the relay power circuit to cut the fan off on the highway and see how it affects things. If it works I would like to look into figuring out a way to wire the fan relay power into some sort of speed activated switch.
Also, did you sell Fritz a GT35R turbo kit years ago? If you did I'm pretty sure it's on my Vert!
I have the same issue and I have a vented hood, my car has the complete Tamon designs front end on it.
It's stacked as such: FMIC, stock oil cooler, stock A/C coil, Koyo rad. It runs plenty cool at sustained speeds but as soon as. I get on the highway and the car gets hot from getting on it good, it stays hot. I think part of it is due to the e-fan I have not turning off and free spinning and highway speed, if I turn the ignition off and coast then cut the car back on it will cool down. Does your e-fan shut off at speed?
I think I'm going to try temporarily wiring a switch into the relay power circuit to cut the fan off on the highway and see how it affects things. If it works I would like to look into figuring out a way to wire the fan relay power into some sort of speed activated switch.
Also, did you sell Fritz a GT35R turbo kit years ago? If you did I'm pretty sure it's on my Vert!
06-25-14, 10:03 PM
#34
Not my pic but visible here on the right of the fan.
They're just rubber flaps, "hinged" at the top and as incoming air increases, they open up to increase throughflow.
When the fan starts, its suction closes the flaps and the fan can only draw through the rad core.
They're just rubber flaps, "hinged" at the top and as incoming air increases, they open up to increase throughflow.
When the fan starts, its suction closes the flaps and the fan can only draw through the rad core.
06-26-14, 08:10 AM
#36
So the condenser is blocking airflow to the radiator? Why don't you just mount it somewhere else? A modern aftermarket parallel condenser may work better anyway. An AC shop should be able to recommend a good solution.
- Divergent inlet duct(s), 1/4 to 1/3 the cross-sectional area of the heat exchanger core(s).
- Convergent outlet duct(s), 15% larger cross-sectional area than the inlet duct.
- Try to avoid placing the heat exchangers in-line, stagger them if needed.
- If you don't run a duct to the hood vent, then be careful when driving the car at high speed until you are sure that no strange aerodynamic effects are trying to rip off the hood or lighten the front end to the point that steering or stability is affected. In theory, the front lip should help keep the front of the car planted and create a nice suction zone over the vent. However, if theory always worked, then there would be no such thing as test drivers or crash test dummies.
- Divergent inlet duct(s), 1/4 to 1/3 the cross-sectional area of the heat exchanger core(s).
- Convergent outlet duct(s), 15% larger cross-sectional area than the inlet duct.
- Try to avoid placing the heat exchangers in-line, stagger them if needed.
- If you don't run a duct to the hood vent, then be careful when driving the car at high speed until you are sure that no strange aerodynamic effects are trying to rip off the hood or lighten the front end to the point that steering or stability is affected. In theory, the front lip should help keep the front of the car planted and create a nice suction zone over the vent. However, if theory always worked, then there would be no such thing as test drivers or crash test dummies.
George,
I have the same issue and I have a vented hood, my car has the complete Tamon designs front end on it.
It's stacked as such: FMIC, stock oil cooler, stock A/C coil, Koyo rad. It runs plenty cool at sustained speeds but as soon as. I get on the highway and the car gets hot from getting on it good, it stays hot. I think part of it is due to the e-fan I have not turning off and free spinning and highway speed, if I turn the ignition off and coast then cut the car back on it will cool down. Does your e-fan shut off at speed?
I think I'm going to try temporarily wiring a switch into the relay power circuit to cut the fan off on the highway and see how it affects things. If it works I would like to look into figuring out a way to wire the fan relay power into some sort of speed activated switch.
Also, did you sell Fritz a GT35R turbo kit years ago? If you did I'm pretty sure it's on my Vert!
I have the same issue and I have a vented hood, my car has the complete Tamon designs front end on it.
It's stacked as such: FMIC, stock oil cooler, stock A/C coil, Koyo rad. It runs plenty cool at sustained speeds but as soon as. I get on the highway and the car gets hot from getting on it good, it stays hot. I think part of it is due to the e-fan I have not turning off and free spinning and highway speed, if I turn the ignition off and coast then cut the car back on it will cool down. Does your e-fan shut off at speed?
I think I'm going to try temporarily wiring a switch into the relay power circuit to cut the fan off on the highway and see how it affects things. If it works I would like to look into figuring out a way to wire the fan relay power into some sort of speed activated switch.
Also, did you sell Fritz a GT35R turbo kit years ago? If you did I'm pretty sure it's on my Vert!
Long story short, after going to FD oil coolers, vented hood, messing with the efan, I pulled that FMIC **** out of the way, and never looked back.
Wish I had the info Evil Aviator posted way back when!
I have been using one since 1996 or so. Granted, I am using the fan, and just the fan, not its shitty thermostat, my ECU takes care of turning on/off the fan.
06-29-14, 03:47 PM
#38
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Yes. There's a lot of history, and I didn't want to get this thread bogged down into a general "my car runs hot" free-for-all. That's why I just posted the question about the vented hood. There are sooooo many things that can affect cooling that I want to look at one issue at a time in order to keep my sanity.
06-29-14, 04:43 PM
#39
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Yes. There's a lot of history, and I didn't want to get this thread bogged down into a general "my car runs hot" free-for-all. That's why I just posted the question about the vented hood. There are sooooo many things that can affect cooling that I want to look at one issue at a time in order to keep my sanity.
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