Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Build Thread - "Carl Winslow"

mechcd · 04-30-2016, 07:45 PM

Fair warning, this posts rambles on and on and on

The cardboard grill block didn't make any appreciable differences

However, I did go whole hog on the heated intake. I got a heater core for a '93 Geo Metro on sale for $10 locally and decided to give it a try

Most people either just remove the trumpet cone thing and make a cut on one side of the box like this. I had already cut the entire bottom out of the air cleaner box to promote airflow.

Mine is well-gutted. The aluminum angle is to keep the filter sealing edge straight. Even before gutting it, it would warp and let unfiltered air into the engine.

The heater core was a very tight fit. It sits just below the filter. The open area by the tubes was blocked with some aluminum chimney flashing. I then just used silver tape to attach the heater core to the air box and seal any leaks. All air entering has to pass through the heater core before going through the filter. The whole assembly is actually pretty sturdy once the top of the air box is snapped on. It doesn't quite fit right because the heater core sticks out 2 inches from the bottom. The tubes and hose are very close to being pinched on the fender liner but are ok for now. Everything just lays in place since the mounting studs are broken due to age. The snorkel seems to keep it all from moving very much.

Once everything was warmed up, the cruise IAT was around 110-120F. I noticed that the throttle needed to be open about 1%-2% more to maintain speed. LFTs stayed between -3% and +4% so the computer's fuel tables are probably correct for the higher temperature range. I'm assuming it also uses less fuel as the temps go up.

At idle, the IAT starts to creep up into the 130F range and the LFTs go down to -12%. This makes me think the IAT isn't accurate since the computer is subtracting fuel. It is stuck in a corner of the airbox and isn't really in the air stream. It's circled in red and the MAF is blue. I used a thermometer to measure the center of the air box temperature through the IAT opening and got readings about 20F higher. The temperatures were close to the IAT values when I put the thermometer in the same spot as the IAT. Time to relocate it?

City driving and traffic lights might be a problem because the temperature keeps going up. Obviously it can't get higher than the coolant temp, but how high is too high? I don't want the already fickle plastic intake manifold to get damaged. I would love to get a nice aluminum aftermarket one but they are phenomenally expensive compared to most other engines. I'm also not sure what the higher temperature would do to the intake valves. The cylinder head is usually around 220F, so probably nothing? I might do some test runs and measure the head temps

(not my car but similar)

I have a few ideas to control the temperature but haven't went through with any of them due to cost and complexity. There is no room to add a fresh air vent or damper to bypass the heater core, so that's out.

Electric solenoid heater valve w/ click-on thermo-switch- $$$ - Least complex
Vacuum operated heater valve - $$ - medium complexity
Cable actuated or manual heater valve - $ - high complexity

The electric valve would use a coffee maker style switch to turn on and off the valve based on temperature. These switches can be found in just about any temperature. Splice in the valve, run 12V to it, maybe a manual off switch, and call it a day. Crude, but quite simple and reliable.

I think an arduino or similar would add too much complexity and potential for it to not work right.

Vac controlled - I was actually considering using a thermac valve or a temp. sensitive vacuum switch for vacuum advance distributors for control. The switch and vac. operated heater valve would make an analog control system. I can't find any switches that go much over 116F though. The valve and actuator would need to be mounted solidly in the vicinity of the air box.

The manual option would use a manual heater valve with a choke cable in the passenger compartment to allow manual adjustment of the coolant. This would also require several brackets to hold everything in place, plus figuring out how to run the choke cable to the dash without it binding up or getting pinched

Now for the numbers!!!!

Run 1 - no WAI
Ambient 52F
Trans: 152F
Engine 186F
IAT - 54F (ambient +2)
Distance - 10.1 mi
Speed - 55 mph
MPG - 22.8

Run 2 - WAI
Ambient 54F
Trans: 149F
Engine 186F
IAT - 116F - the sensor is in a bad spot, it is probably getting much hotter
Distance - 10.1 mi
Speed - 55 mph
MPG - 26.2

Run 3 - WAI
Ambient 50F
Trans: 149F
Engine 186F
IAT - 114F
Distance - 10.1 mi
Speed - 55 mph
MPG - 25.8

Run 4 - no WAI
Ambient 51F
Trans: 160F
Engine 186F
IAT - 52F
Distance - 10.1 mi
Speed - 55 mph
MPG - 24.1

Looks like a success to me!

04-30-2016, 07:45 PM	#7 (permalink)
mechcd EcoModding Lurker Join Date: Dec 2014 Location: Ohio Posts: 11 Carl Winslow - '02 Ford Crown Victoria Police Interceptor 90 day: 23.89 mpg (US) Penelope - '99 Pontiac Grand Prix GTP 90 day: 31.96 mpg (US) The Saabray - '84 Honda VF700S Sabre 90 day: 30.36 mpg (US) The (Silver) Ghost - '99 Ford Crown Victoria Police Interceptor 90 day: 24.26 mpg (US) Thanks: 0 Thanked 4 Times in 3 Posts	Warm Air Intake Fair warning, this posts rambles on and on and on The cardboard grill block didn't make any appreciable differences However, I did go whole hog on the heated intake. I got a heater core for a '93 Geo Metro on sale for $10 locally and decided to give it a try Most people either just remove the trumpet cone thing and make a cut on one side of the box like this. I had already cut the entire bottom out of the air cleaner box to promote airflow. Mine is well-gutted. The aluminum angle is to keep the filter sealing edge straight. Even before gutting it, it would warp and let unfiltered air into the engine. The heater core was a very tight fit. It sits just below the filter. The open area by the tubes was blocked with some aluminum chimney flashing. I then just used silver tape to attach the heater core to the air box and seal any leaks. All air entering has to pass through the heater core before going through the filter. The whole assembly is actually pretty sturdy once the top of the air box is snapped on. It doesn't quite fit right because the heater core sticks out 2 inches from the bottom. The tubes and hose are very close to being pinched on the fender liner but are ok for now. Everything just lays in place since the mounting studs are broken due to age. The snorkel seems to keep it all from moving very much. Once everything was warmed up, the cruise IAT was around 110-120F. I noticed that the throttle needed to be open about 1%-2% more to maintain speed. LFTs stayed between -3% and +4% so the computer's fuel tables are probably correct for the higher temperature range. I'm assuming it also uses less fuel as the temps go up. At idle, the IAT starts to creep up into the 130F range and the LFTs go down to -12%. This makes me think the IAT isn't accurate since the computer is subtracting fuel. It is stuck in a corner of the airbox and isn't really in the air stream. It's circled in red and the MAF is blue. I used a thermometer to measure the center of the air box temperature through the IAT opening and got readings about 20F higher. The temperatures were close to the IAT values when I put the thermometer in the same spot as the IAT. Time to relocate it? City driving and traffic lights might be a problem because the temperature keeps going up. Obviously it can't get higher than the coolant temp, but how high is too high? I don't want the already fickle plastic intake manifold to get damaged. I would love to get a nice aluminum aftermarket one but they are phenomenally expensive compared to most other engines. I'm also not sure what the higher temperature would do to the intake valves. The cylinder head is usually around 220F, so probably nothing? I might do some test runs and measure the head temps (not my car but similar) I have a few ideas to control the temperature but haven't went through with any of them due to cost and complexity. There is no room to add a fresh air vent or damper to bypass the heater core, so that's out. Electric solenoid heater valve w/ click-on thermo-switch- $$$ - Least complex Vacuum operated heater valve - $$ - medium complexity Cable actuated or manual heater valve - $ - high complexity The electric valve would use a coffee maker style switch to turn on and off the valve based on temperature. These switches can be found in just about any temperature. Splice in the valve, run 12V to it, maybe a manual off switch, and call it a day. Crude, but quite simple and reliable. I think an arduino or similar would add too much complexity and potential for it to not work right. Vac controlled - I was actually considering using a thermac valve or a temp. sensitive vacuum switch for vacuum advance distributors for control. The switch and vac. operated heater valve would make an analog control system. I can't find any switches that go much over 116F though. The valve and actuator would need to be mounted solidly in the vicinity of the air box. The manual option would use a manual heater valve with a choke cable in the passenger compartment to allow manual adjustment of the coolant. This would also require several brackets to hold everything in place, plus figuring out how to run the choke cable to the dash without it binding up or getting pinched Now for the numbers!!!! Run 1 - no WAI Ambient 52F Trans: 152F Engine 186F IAT - 54F (ambient +2) Distance - 10.1 mi Speed - 55 mph MPG - 22.8 Run 2 - WAI Ambient 54F Trans: 149F Engine 186F IAT - 116F - the sensor is in a bad spot, it is probably getting much hotter Distance - 10.1 mi Speed - 55 mph MPG - 26.2 Run 3 - WAI Ambient 50F Trans: 149F Engine 186F IAT - 114F Distance - 10.1 mi Speed - 55 mph MPG - 25.8 Run 4 - no WAI Ambient 51F Trans: 160F Engine 186F IAT - 52F Distance - 10.1 mi Speed - 55 mph MPG - 24.1 Looks like a success to me!