I came to this channel because of the Honda Insight, and I’m sticking around to see it again! I’m ready to see what the Predator 670 will do in it

I had a brutal commute during the dubya gas crisis and with a vacuum gauge regularly averaged 41 mpg in my '90 Accord (27 EPA hwy rating). It's amazing what you can do with even basic instrumentation.

I think what you said about controlled testing is VERY important. The hardest thing is recreating a test under "real world" driving conditions. As much as you can reduce the human differences in testing, the better. PS - That Saturn wagon looks like a candidate for EV conversion. Lotta room for batteries, :) .

I have a vacuum gauge mounted next to the tach in my old truck. It's amazing all the information you can get if you think about it. Thanks again for the best Sunday Morning Cartoons on TV.

You could add a safety like having an emergency stop button disabling fuel injection. No fuel = no power... For full power you could disable the fuel economy mode if the pedal is over 80% depressed.

Your acceleration runs are getting better fuel economy than my pickup truck. Man I miss those days when all I had to cart around was my own skinny ass and I was getting 30+ mpg doing it.

THIS is the most entertaining stuff I have seen on KZfaq for a long time. Disclaimer: I have owned and used a Scan Gauge. I have owned 3 Prius (Prii?). I have added an aftermarket 6 kWhr battery pack to a 2014 Plug-in Prius. I have done a few of these tests myself, off-camera. Disclaimer: I have a degree in electrical engineering and a fetish for MPG. Keep up the fun!!!

That tiny gnome cameo was not enough! Where oh where am I going to get me gnome fix? 🤔

This channel is making me like Saturn's and insights. Neither of which are something I ever thought I'd say

You are one of the few KZfaq channels I look forward to seeing on a weekly basis and wanted to tell you thanks for the great content.

Can’t wait to see the robo throttle and lean burn working together and what fuel economy will be

You can set the auto off (mpg increase off if TPS) is over 70% WOT. So floor it and gives better acceleration. This makes more programming but does a away w the Pot. First 70% of accelerator position is only 40% of WOT. Last 30% is 60% of the added TB. To make it easy to know where the MPG change kicks in add an extra throttle return spring that kicks in only at the 70% WOT so you feel it in the foot too.

Great video! Add to Robo-throttle kick function similar like for automatic gearboxes.. Fast pedal release and then fast flooring deactivates fuel saving until next pedal release, holding Robo-throttle wide open.. 😉

Irony is, such feature (maintain an optimum MAP) was present in 80's Skoda 120, implemented in the way how the two barrel carburetter was controlled: There were two butterfly throttle "parallel" (so the mixture had two paths to go through), one (primary) was controlled from the pedal cable directly, but the second was controlled by a diaphragm responding to the MAP. But there were two links from the primary to the secondary: When nearly closed, a cam forced the secondary butterfly closed when you completely release the pedal (about below 20%). And then when you depress it (beyond about 70..80%), it forces the secondary open as well, to allow full power on a kind of "kick down". Overall when you maintain the pedal position between the 30..70%, the MAP was maintained at the optimum efficiency level. Drawback was, it felt like the car "had no response on gas" until you really fully depress it. And all that without any electronics... For your setup, I would implement the "robo throttle" to gradually open over the last ~20..30% of the pedal position, so you don't need to operate any switch when wanting to accelerate, just full pedal will effectively deactivate the "robo throttle"...

I suggest you leave it between gears as this is where the best MPG seems to reside!

Hillbilly proving grounds has to be the biggest misnomer for a place with no hills.

Very nice work! After some software tweaks it can be a very good way to upgrade an old car. The dual throttle body is a good failsafe solution.

I would have NEVER EVER thought so little on road HP would interest me so much.

I installed a turbo disable button on my 1.0L 3cyl Fiesta - caps it at basically 70whp by opening the wastegate fully. When I go WOT, the PCM opens throttle 100% which is fun to watch - only after 30 seconds it will trigger an under boost code, but by then I'm already going above 60mph. Turbo disable will guarantee 52mpg.

At the heart of gratitude, kindness and compassion can be found.

I lol'd at the Uno part

Discovered this channel when it was a little smaller. Happy to see Robert cantina taking off!

My 1991 Mercedes 300SE has an "Economy" gauge that is driven by vacuum pressure. That was the last year of the last old school S class that was way out of date in 1991.

Thank you for applying a logical application to your experiments.

"Uno means one in Italian, but thats not relevant to our story." Gave you a like.

This maybe a bit sadistic but I love tuning PID's. That feeling when the stars line up is just the best.

Commenting for the algorithm, because Jimbo deserves it. Cars + science = Fun

Ahh, J.C. Whitney! Bought quite a few things from that catalogue in the 1980s. When I was a younger lad I had (and still have) a garage sale vacuum gauge, a huge thing with a brass bezel, clearly not aimed at automotive diagnostic tool use. On my 1970 Volvo 145S and a later 1979 Volvo 240 wagon, I'd string a hose from the engine and set the gauge on my dash where I could watch it. It made a little bit of difference on the 79' to watch it but 1970 with its ZS 175CDS carbs flushing fuel down their gulet just wasn't precise enough to get much of a milage tweak from watching engine load with the gauge. Sorta wild today to think I have a 1970 Volvo (a rather ragged 142S) again, I've come full circle.

Another gold standard film mr

I live near Topeka Kansas and for over a decade I have been building gadgets for my car . Hydrogen scam stuff and now I run my car with Propane.. I used basic stamp MC to manage my AF ratio... I am absolutely loving every precious minute of your show.. Following in your footsteps I got a 1995 ford escord wagon and just got it running on propane.. horrible mpg ... 22.... need that robo throttle.. maybe I will try and lean my propane mixer down a touch.. my propane mixer is a pvc T and a water valve.. slightly close it a bit and it goes leaner... stone age technology!..

Future Jimbo: It works! 😆

You Seriously need more subscribers I’m liking a sharing as much as Possible

GAHHHDDDDD I love your videos. I learn so much and your, "fuck it, lets try this" attitude is so appreciated.

I’ll be honest, idk why I watch you videos, but I think I’ve watched most of them. Good job! Been teaching me about things I wasn’t motivated to learn myself even though I’m in a relevant industry.

It's been a while, but I could swear that a '98 BMW 540i that I owned also had 2 throttle bodies. One was a manual connected to the pedal and it was mounted on the upstream side (closer to the airbox). Then there was another throttle body behind it that was normally open which I think was used as part of the traction control system. I could be remembering wrong, but I thought it was a pretty cool way to implement TC and still not be full drive-by-wire.

I've seen the mpg gauges that ran off vacuum, I always thought they were a scam, i didn't realize it was actually good. Uhaul trucks use them a lot too.

Very cool work. I hope to put more of my programming and electronics experience to good use in the future like you!

Some older cars with primitive traction control systems actually used systems fairly similar to this (with the combination of mechanical and electronic throttle bodies) but the implementation was a little different. The mechanical throttle body was used for most operations and the electronic throttle body would be wide open most of the time, but when wheel slip was detected, a separate module controlling the electronic throttle body would command the electronic throttle body partially or fully closed to reduce engine power output and reduce the wheel slip. Some early electronic throttle body systems would also use remote mounted accelerator position sensors that were connected to the throttle pedal with a traditional throttle cable. Some of them even mounted the APP sensor directly on the throttle body. Honda mounted the APP sensor on the firewall, and I think some Toyota, VW and Audi models mounted it on the throttle body.

Good work Jimbo, I appreciate your efforts.

I learn alot from this, and i want to learn more of how to tune mega squirt. so that is how i found this channel👍

"Even I am uncomfortable with this experiment"... Sounds like fun.

Some motorcycles today have modes, such as "Economy," "Normal," "Sport," and "Performance" or "Race" that probably work similarly, also taking wheelspin into account by reading the anit-lock brake tonewheel/encoder on the front and back wheels. A lot of these technologies have been used in industrial automation for decades, and as an industrial electrician, I'm quite familiar with the concepts, if not so much with the code used. I did have to write a program for a can crusher in a class years ago that used a crude encoder, 2 sensors to determine direction, a motor, and threaded rod. I kept tweaking the code for features and efficiency long after the project was done and graded, because I had so much fun doing it.

Tbi map sensors in mopar 2.2’s. Bane of my teen existence

Most people have no idea how exhausting it can be to hypermile, ESPECIALLY on long distance trips.

This is basically an electronic engine governor. That's pretty cool.

Hey mr Jimbo, I think you may have had better results with lower manifold pressures but shifting earlier. I think the main reason that vacuum gauges worked so well on carbureted engines is because of the enrichment that occurs at wider throttle. if the saturn were leaned out but had a wider throttle and shifted earlier, you'd have much lower pumping losses, fewer ignition events/meter travelled, and much lower internal friction due to having to move the pistons up and down fewer times/meter travelled. also cam timing, exhaust/intake manifold/port design are much suited to lower rpm as well. i think just a purely vacuum based robo-throttle would yeild better results on a primary/secondary throttle style carburettor than on a modern MPFI system. i always love these experiments, please continue making them!

If KZfaq is correct, this will be available at 11:00pm Australian Eastern time! Do I sleep and wait till tomorrow or stay up late and maybe sleep in tomorrow if I am unlucky and possibly be late for work, what to do, what to do??

The double throttle actually “doubles” as a Saftey feature, if the robo throttle gets stuck open, your normal throttle still works, so you won’t ever runaway

You know what Sunday is, naps, Robot Cantina and potential for mayhem.

LOL on the Ferrari decals. I had an SC2 back in the day with the pop up headlights. The factory color was tan, which I hated, and the paint was pealing, so I spontaneously did an Autozone paintjob in my rental's garage over a weekend and painted it what turned out to be a very bright but matte red (the clear would not lay flat because it was reduced with acetone per the manufacturers recommendations, so it was drying before it hit the surface). Anyway, I had put a set of daisies on the car just prior and did a halfway decent silver metallic paint job with good wheel paint on those, so they looked really nice and shiny. The car actually didn't look too bad when I was done honestly, but I was just trying to get rid of the ugly color and those hideous turbine wheels. The car was a beater commuter car. Anyway, I was driving through the neighborhood one day after all the cosmetic work and I rolled up on some young kids playing in their front yard and so I slowed right down to like 10-15 mph to make sure I could stop if they darted out, and as I rolled by the younger boy goes "Hey look! There goes a Ferrari!" and his older sister goes "That's not a Ferrari!" all mad. I laughed all the way home when I heard that.

Those deer 🦌 didn't want robo throttle to have any fun.

Let this Sunday be a rainbow for your entire upcoming week🚴‍♀🚴‍♀🚴‍♀🚴‍♀🚴‍♀🚴‍♀

imagine the market out here that would buy this to put on their kids cars to limit their speed and lack of full throttle ability .. i really do think you are onto something great and am very much looking forward to see what kind of results you get when you have it tuned in

Very clever design. Always looking forward your updates.

Man, if you ever get pulled over in that thing, you're gonna have a LOT of explaining to do.

This is some of what I was looking at, but a bit further, for a commuter, if you use a datalogger and map the speeds, you can let the "robotic throttle" use an optimal acceleration based on situation. a more simple solution would be have it only modulate the throttle under 60% throttle, or use a data set to watch for acceleration requests vs constant speed. cool project though!!

you always get my like, i can see that 10 cents from my like goes a long way lol. keep it up jimbo!

I love whenever I see a new video from you. I am going to start doing similar projects on my 97 Passat TDI 😎

Great work Sir thank you

To correct the lag in performance, I would think to have it ignore fuel economy adaptations when tps is requested like over 65% or whatever. Or a neat way would be to have something like a kick down switch/range? I don't know for sure but I love these types of videos!!!

It’s always good to see another video in your project series. And from a fellow New York native who now lives in rural Kansas, I fully understand what you mean. 😅

I dream of souls that are always free, like clouds that soar.

the stacked throttle bodys reminds me of yamaha sport bikes right after they did away with the constant vac slides in the efi systems but right before they went full fly by wire

I don't always tell people where I hunt, but when I do it is a lie.

I have a 1996 cadillac 6 door limousine with the original 5.7l LT1. and i can get 30MPG out of it if i put effort into it, and if i have all the patience in the world i can get 35MPG, but this requires no hills or stops at around 40-50MPH with an ambient air temperature around 90f or higher.

Robot self driving

This would make a great way to keep your Teenager's from racing around in your car and you could put a key lock on it so you could lock it on or off.

Here is a crazy idea : an accelerator pedal accelerates , however if you don't press it the car should maintain speed. What I am trying so say is : use the robo-throttle to maintain speed in the most efficient way possible when the pedal is not pressed. For many reasons I will have to leave the really hard part to you because :1/ i don't have the car ,2/ the tools , 3/25 years of experience, or 4/ programing knowledge. Anyway I hope you find the idea sufficiently interesting to test it.

Omg this is something I've wanted to try for years!!! Thanks

Have you considered a project on reverse cruise control? Instead of not letting the car drop speed, just limit the speed you can achieve, have safety features of disabling it temporarily if the pedal is pressed substantially far or all the way. You could also add in a feature of throttle smoothing where minuscule changes in throttle would be ignored unless enough to account for a slight hill or preemptively adding throttle to go up a modest hill.

so basically you made a secondary throttle plate like there are in motorcycles (my 20yo gixxer has that), theoretically you could increase low down torque just a bit by making proper adjustments. love ur vids btw, keep up the work

Simply fascinating. I do appreciate your talents but I must admit I really miss the big block supercharged Honda and remain optimistic it will soon return. Thank you for continuing to make fun and enlightening videos.

i love this and i love saturns. such great cars.

The 2002 and later Acura TL Type S had a similar dual throttle body system. Acura's vehicle stability assist system needed some way to reduce engine power, and they weren't confident with going full drive by wire. So, vehicle stability assist would just close this secondary throttle body to limit the engine output, and thus limit wheelspin.

I’ve done a bit of ecu tuning for power on various cars. I noticed on older ecus, accelerator pedal position was basically linked to a desired throttle opening. Sometimes linear, sometimes not, but the relationship could be easily manipulated. Now the new ecus use accelerator pedal position to calculate a desired torque, which then correlates to a throttle opening. I think this video/experiment helps explain why OEMs are doing that. At lower pedal positions its effectively doing what you are where it’s removing the human error element for better mpg. But at higher pedal positions it can still give acceleration when needed.

Only the guy who isn't rowing has time to rock the boat. ⛵⛵⛵⛵⛵⛵

I'm pretty sure my 1995 Lexus LS400 has this from the factory and I will say it does work. My little 4.0l V8 gets around 20-22mpg on the highway and around 18 overall.

Absolutely insane. I love it so much. You're awesome.

Fun experiments!

I love this little Saturn. I'd love to see all your systems working together to see what kind of mpg you could get! You earned my sub

You are making this so interesting! Thanks for the effort, I’m really enjoying it.

Great result! This set up reminds me my 1997 E39 BMW 5 series also has a similar unusual double throttle bodies set up. The throttle body connected to the engine is a normal throttle cable controlled one, the extra throttle body is controlled by computer functioning as traction control (temporarily closed to take away power when the wheels slip).

Yeah, the Ferrari decals will definitely impress the chicks, at least that’s what they tell me. ;-)

Outstanding job on the explanation.. very insightful. 👍🏻👍🏻 But i'm dying of anticipation for the diesel swap. I just know it's gonna be great.

Wait, Future Jimbo visited you from the future? Did you put a Flux capacitor in the Saturn wagon? Do the Gnomes join forces with skynet to conquer humanity? Where is episode 13? Jokes aside I love the "what if" motivation behind all your projects.

"hopefully it'll impress the chicks." *has beevus and butthead mouse pad* 😍😍😍😍

An additional throttle body is capable of preventing poor driving behaviour, but it also adds to pumping losses for those who use their gas pedal wisely....I averaged 5.2 litres per 100 km on a stock saturn SL1 fully loaded with gear for a 2 week camping trip through the rockies, while drive up into the rockies! Truth is that these cars make great gas mileage from the get go

Wonder how the Saturn would perform with full maintenance, fluids, filters, oils, plugs, wires & coils. On top of all that a re-written ECU tune optimized for fuel economy. Could it possibly break into the 50MPG range?

Hoping for a two stroke diesel running on woodgas :D

I need a robot throttle for my pizza delivery cars. Save tire wear, save gas, maybe less repairs on the car.

This is pretty much what eco mode on many DBW cars do, only those aren't often optimized for responsiveness, and you'll have an over-ride switch activated at something like 1/2 to 3/4ths throttle, or, if you're driving a Mazda, via a joy buzzer on the floor under the pedal.

I forgot to mention this on the previous lean burn video: you probably want to add the offset to the wideband O2 sensor before the conversion, not after conversion to narrowband. With your previous setup I believe you were limiting the useful range of the sensor. Hopefully you consider this before the next episode.

MAP is absolute pressure, so I imagine that 7-8 PSIA is -8 to -7 PSIG on a "normal" gauge where 0 PSIG usually equates to around 14.7-ish PSIA. If you weren't (rightly) worried about endangering yourself and others, you could program the throttle ramp for perfectly repeatable test runs. Or could, I suppose, if someone didn't still need to shift the gears. If only someone would automate transmissions already...

Excellent as usual !

Great video, Jimbo! Keep the cool experiments coming. 👍

I think it's neat how you take the mystery out of some of these sensors and put together cool experiments at the same time.

Damn you're smart even when you dumb it down I still find it hard to understand. Awesome job and great content.

I love your channel and I sent some moola to show how much I appreciate it. You have gotten me through some dark days and this channel has been a spiritual re-awakening. Thank you so much!

Feeling blessed, never stressed... Got that groove on for my Sunday best. 😇😇😇

I think that you can essentially put a low velocity shutoff in the controller. If you are below 25 MPH your fuel economy is not optimal anyway (unless you own a prius and you dont use AC). Therefore doubling the power output is not seriously going to detract the feul economy since getting to an ideal 45 mph faster is going reduced the impact of maximizing MAP. However as you surpass 25 MPH the map sensor should incrementally increase the minimum optimal MAP pressure to 45 MPH when no more speed economies can be achieved. Alternatively you could link the Minimum MAP to the gear with so that MAP pressure range varies with transmission gear ratio.