Fun with RAM Air... or not

[itjstagame]

Ok, so I have been playing with a couple different setups on my Saturn SW2. I started with HAI pulling from behind the exhaust manifold and then thought that maybe I should pull from the air dam and run behind the header and then in, so maybe I could get heated ram air.

I have since actually read up on ram air and how little you can expect (I think I saw something like 0.1psi at 60mph or so and 0.2psi at 120mph).

Anyway, the 'ram' was a 3" hole in my air dam through 3" heating duct past exhaust header and into a new hole in side of stock air box. Ducting taping everything liberally, but clearly not 'sealed'.

I did 1 run to/from work with HAI, then 1 with RAM and today back to HAI. I have numbers but they are not super telling:

Date of Run	Direction		Mins	Gallons		Miles 	MPG		Idle gal/hr	AVG IAT		Mode IAT	Max IAT	AVG Boost	Mode Boost	Max Boost
5/2/2012	To Work		HAI	60	1.002		54.6	54.49101796	0.2		122.9		122		136.4	-7.528		-10.784		0.239
5/2/2012	From Work	HAI	45	0.7238		37.802	52.22713457	0.209		129.26		127.4		156.2	-7.392		-10.784		0.09385
5/3/2012	To Work		RAM	45	0.825511111	38.281	46.37248304	0.22		78.46		78.8		95	-7.44		-10.639		-0.05
5/4/2012	To Work		HAI	68	0.924584444	49.42	53.45103987	0.188		166.29		168.8		185	-7.6153		-10.639		0.239

All of these runs are engine on P+G from 50-60mph, although looking at the mins >60 is due to stop+go traffic for 10-20 mins everyday. My From work didn't go through from RAM, phone was spasing out, but I did have gauges for a while and it was the same thing. Clearly more vacuum and could see/feel the less MPGs. The average vacuum looks higher, but I think that's because I was pulsing longer (with less power). I can definitely feel more power with the HAI, I need to do a run with stock to confirm but it really feels like more power than stock too. I did read that cooling the exhaust header should increase power and scavenging (helping 'pull' exhaust from the cylinder to the cooled header), although I doubt my HAI is having that much of an effect, it does make me wonder what heatsinking to the hood would do :-).

Basically, I dropped MPG with the RAM Air and noticed increased vacuum probably due to colder air and longer pipe. I then thought, maybe I just need a larger scoop, information online suggests that somehow the scoop size doesn't matter, but I don't fully understand that.

So I did some before/after runs with 3" RAM and with a 4"x10-12" ducting that reduces to the same 3" pipe (I can post a picture if it doesn't make sense, looks like a vacuum cleaner).
Anyway, I have numbers for that too, but not much too see, it looks like it might have .2psi less vacuum at idle and maybe .1psi less at speed but never went positive at 65mph. Either way the HAI had less vacuum (probably due to less density).

One of the suggestions I read was pulling the ram air from behind the radiator. This might still be something I try, moving the fan just a little bit will give me 4"x10" for my 'scoop' and then I'd have warmer air, sort of 'rammed' and could still run past exhaust header. I know any gain would be super minuscule though so definitely not a top priority.

Of course it might be 'easier' to just put a small turbo and somehow resist the urge to run boost (my goal is just to decrease vacuum and warm air, turbo would do both but more money and more involved).

Anyway, thoughts, comments, suggestions?

[Frank Lee]

HHO and VGs next on the list?

[t vago]

Uhm... What's the point of ram air for eco-driving?

[itjstagame]

Well I am just playing around now that I have Torque to get data and things. The point of Ram air would be to decrease vacuum/increase VE. Same reasoning of a turbo, except turbo also gives better thermal efficiency. Clearly though, ram air doesn't work at all in the sub 60mph we drive :-).

As for HHO, I played with that in HS to try to increase the 8MPG my Caprice 9C1 got :-), but that was long ago and instantly lead to the 'why does it rev down like its under load when connected'. I still think there could be something there and have read plenty of different plans with pulsing the power to the unit, using PWM, and maybe if you can control the power consumption and somehow a 'very little' HHO actually aids combustion somehow then maybe it'd do something. Still I don't have the time to mess with such things now.

Next on the list is warming the fuel from the heater hose and putting in a 195 thermostat. See if that combined with HAI will help or not.

Aside from that I'm slowly working on wiring in an old Megasquirt 1 I have from an ancient project that never materialized. The goal would be to buy a wideband and try to lean out my cruise within reason and at least have control over fuel that gets used.
I'm also trying to get a '98+ MP2 5th gearset that I think will prove useful for the times I need to go 60-70MPH instead of 50-60MPH.

As for as less proven ideas, something I've always wanted to try but requires more time and money that I have an doesn't make sense on my daily; would be to put a small turbo on it. Turbo can definitely help with efficiency, and once megasquirt is already wired in shouldn't be that hard to tune for. The 'less proven' part would be that I would like to put an injector before the turbo and have the intake runner get heated by the exhaust manifold some. The goal being to try to mix the fuel as much as possible and have the intake charge already have some fuel in it, say at 25:1 or 20:1 or something and then we can add more fuel from the main injectors while intake closing. Basically try to stratify the charge a bit while following the turbo/heated intake idea of Smokey Yunik.

Beside that, something that I've never seen attempted before, would be to make a parallel hybrid, remove the starter, rewind or buy a motor, build a motor controller, hook to flywheel (at something better than the stock 7:217 ratio (off the top of my head, but have looked it up before)) or use chain drive to output shaft from engine or something. Or, just thought of, but some engines you have easier access to front of crank shaft. Maybe could use a platter style motor (like in electric fan or clothes washing machine) and replace/hook to the harmonic balancer. Goal being that we can remove starter and alternator and have one 3-phase drive with regenerative capabilities. Hardest part is programming the controller, my 'dream' would be to leave the car in 5th gear all the time, at a light, engine is off, at <25mph I am using electric motor to drive the car and the 'dead' engine (which shouldn't be too bad at the <1krpm) and light off engine when above 25mph/1krpm. The goal while actively driving >45mph would that I can use this to help with P+G. That is, if I am clutch in and not in gear then engine off, 0rpm, if I am in gear, clutch in, then let CPU/motor controller/something rev match the engine using electric so I can engage clutch and pulse. It also adds the possibility that if I have enough battery charge and only a slight hill that I could electrically assist the glide, same as warp stealth on gen 3 Prius.

I'm working on the motor-controller/programming now because I see that as the hardest part, but it only gets spare time and I'm not really a microcontroller programmer and electronic/circuit knowledge is average at best. So it'll probably be another project that never happens, but everytime I'm stuck in stop and go traffic I think about how nice it'd be to use 0gph the entire time and only electrically 'pulse' a little as we crawl along at 5-15mph.

[t vago]

Originally Posted by itjstagame

The point of Ram air would be to decrease vacuum/increase VE.

How does ram air manage to do this?

Keep in mind that there's a restriction in the intake, that was deliberately placed there so as to throttle the air going into the engine. The point of this throttling is to cause the engine to output a set amount of power that is much below its maximum power potential.

[gone-ot]

..."pushing / ramming" more air into the engine means it shouldn't have to work as hard during its "intake" cycle...remember, the ICE is just a "...self-propelled air pump..."

...however, cold air is best for power, not FE.

[t vago]

Originally Posted by Old Tele man

..."pushing / ramming" more air into the engine means it shouldn't have to work as hard during its "intake" cycle...remember, the ICE is just a "...self-propelled air pump..."

Isn't that kind of pointless, if there's a restriction deliberately placed there that serves to artificially increase the pumping losses? So as to limit engine output below its maximum capability?

[Frank Lee]

Originally Posted by Old Tele man

..."pushing / ramming" more air into the engine means it shouldn't have to work as hard during its "intake" cycle...remember, the ICE is just a "...self-propelled air pump..."

...however, cold air is best for power, not FE.

This is a road well traveled- haven't you been down it already?

[gone-ot]

Originally Posted by Frank Lee

This is a road well traveled- haven't you been down it already?

...how so, Frank? Let's hear your 'road-song' on this subject.

FWIW, an ICE engine being operated for maximum power output is commonly at full-throttle and thus basically has NO throttle-restriction (anymore). And, under such conditions cold air is more beneficial to increased HP --which is part of the OP's experiment -- while, conversely, hot air is better for FE, which is what he sought (I believe).

[Frank Lee]

Not even OP's goal is max power at WOT. Tvago summed it up pretty well already in #5.