Robot Cantina: I hate doing fuel economy tests! Proceeds to do 5 fuel economy tests in one video.

This IS the only channel on KZfaq with this kind of content.

The saturn turbo diesel is the most incredible car ever ! ❤

You know, its current acceleration makes it a perfectly acceptable "around town" driver that would beat the pants off most cars for gas mileage. I really like this little car. :)

I'm very jealous that you can spent your time working on these projects. Thanks for documenting the fun and sharing with us!

The air-cooled Volkwagens are known for using CV-style carburetors as well... hence why they typically got such good feul economy from the factory. And at one point, they decided to go with a variant of Bosch's Jetronic EFI system. (Every multi-point EFI on the road pretty-much is...!😉) It worked well... until they discovered American CB-radios were able to generate a strong signal on the same operating frequency as the un-shielded ECM that it employed, resulting in many frustrated VW owners on the roadside wondering "Why the F@$# did it suddenly shut-down!?!"😆

I drive an Excursion, and after seeing all the fun with this car it makes me want to consider something tiny to tinker on.

I’m happy you’re going with a variable Venturi carb. My British cars have SU carburetters which are variable Venturi.

The ram air failed because you did not adjust the mixture to compensate. Gotta richen that mixture. But I agree to get the carb you’re going to use first. Once you pick a carb, the ram air can be a focus. Good job. Fun stuff.

Loving every bit of this series. And I 'm sure the Saturn will get a decent farewell.

Dude, I love the fuel consumption figures. Please don't stop doing those! I want to do an in line hybrid of sorts and that helps me out a lot!

Thanks for the recap of the progress so far. It's hard to believe you've been able to make such an improvement with relatively little modification. I totally understand wanting to tune the engine performance before tuning the transmission. The engine develops the power according to the load, while the transmission converts it to the appropriate torque for the current speed. The tuning of the transmission will greatly depend on the power curve of the engine, whereas getting power out of the engine is its own thing. And whatever you do, you don't want to change a bunch of things at once, otherwise you won't know what change made the difference.

Note to OP: Re: Cowl Induction. It's well-used in NASCAR as a way to create a "Ram-Air" effect with inlet air to the engine.😉

Tune in next time when Jimbo powers a M1 Abrams tank with a 3.5cc 4 stroke Toyan engine! Joking aside, I love this channel and the thorough testing- it never ceases to amaze me with what you can get away with yet still be drivable.

If you are interested in what fuel costs in Germany. Conversion rate is $1.09 for 1€ Today here in Bavaria/Germany: Gas= 7,82$ Diesel= 7,08$ for 1Gallon I think twice about taking out my Corvette😊 . Thanks for the conversions to the metric system. Great Video👌👍.

That last 55 mph test was great! The car sounded like it stayed in the power band and kept pulling! I am enjoying this project! Very impressive gains!

As always, this was a amazing and enjoyable video. I love the concept of slapping together a car and getting the most out of it. Makes me want to do it sometime.

So I love the straight edge across with fuel cell with the combi square for measuring the fuel level, but to increase the accuracy how about a little gnome in a boat acting as a float holding up a stick, fill the fuel cell up until the end of the stick reaches the same point on the combi square every time

I usually finish my Saturday evening watching some carnage in an I Do Cars engine teardown, and then enjoy my morning coffee on Sunday catching up with what Jimbo and the crew have done with lawnmower powered classic French tourers. It's a nice contrast of things that don't work, and things that do even if they shouldn't. Love it! Heat this week is no joke, stay frosty, gentlemen!

With the "Ram-Air" system a friend built on my '85 S-10 pickup, it drew from the "clean" air seen by the lower front-end air dam. Also: The GM/Bosch TBI system (EFI) was able to compensate for the change in inlet air mass & temperature by constantly monitoring and adjusting the A/F-ratio in accordance to input from the numerous inputs it employed, as well as referencing the programmed fuel mapping "burned" into its PROM (Programmable Read-Only Memory) chip. The result: Avg. 25-mpg@77-mph cruising speed!😁

We need more episodes of this, I know it's difficult. But really.. We need more Great job as always and keep it up

The pressure from the ram air system also needs to connect to the vent of the float bowl. The jets work on the pressure difference.

Well done to Performance 670, it made your life much easier. That said, $3.50 a gallon is only about $1 per litre, you get no sympathy from me :-) It's great to see this quirky French car back on the road.

I like the "dare to be different" approach to the carburetor selection. And I hope the Saturn gets another motor. Try to find something really weird that nobody has heard of ever to put in it.

This is probably my favorite channel on KZfaq. I stumbled upon it at the beginning of the Saturn build. I look forward to every video! Keep up the good work!

An old trick I've seen done to help with the fuel's phase change is to heat the fuel before it enters the carburetor, done "quick & cheap" by running the fuel through a length of copper tubing wrapped around a "waste" heat source (heater hose or an under-hood exhaust part) placed in a point along the fuel line's delivery path AFTER the fuel pump or fuel filter.

Thanks for producing such interesting content. I look forward to Sundays so I can watch your latest efforts. Phil

$3.5 dollar a gallon is a great deal. Here in the Netherlands we pay €2 euro a liter....😮

Thanks for the sunday moneing entertainment jimbo! Coffee and robot cantina is my favorite way to start the day

I just love that old car. You still find some of them in Denmark.

I used to drive a Renault R10 back when I was in High School (1974-75). I loved the front seats in it and it also got great gas mileage back then. When I came to driving it in the snow it was much better than than rear wheel drive cars of the time. It also had Michelin X radial tires on it. Radial tires were unheard of back then. My dad later replaced the back tires with a set of bias-ply tires. This made the car extremely unstable to drive as the rear of the car wanted to fishtail on every curve. It would be neat if you could find a person who still owned an original R10 and have a race between yours and the original car with the 4-cylinder engine. Thanks for posting these interesting videos.

Cool, i hadn't seen one of those constant velocity something carbs before, but it immediately reminded me of the legendary 'constant depression' SU carb. Cheers Jimbo!

For you who cares😅 - I was the owner of an BMW 530d A (e39) it had a 3.0 turbo diesel and ran 5.7ltr/ 100km at around 100km/h (60 miles) the car weight was 1880kg and had a topspeed 247kmh and 0-100 at around 6,7sek. I kept that engine for a boat but sold it cheap before knowing this channel.

Thanks Jimbo, I always enjoy checking in on the Cantina!

The reason VW probably found the exhaust thingy to improve power is because you don't want your fuel to vaporize before getting into the combustion chamber; if possible while still getting good atomisation. It's one of the reasons direct injection is better for fuel efficiency and why it lends itself well to higher compression engines. Latent heat of vaporization is a pretty powerful thing when it comes down to engine performance and even though petrol/gasoline is almost laughably weak at pulling heat from the air around it to do so, it still makes a massive difference for engines. It's also why you can make more power on E85 even though the specific energy of E85 is far lower than petrol/gasoline, the simple fact that ethanol pulls much more heat out of the air to vaporize cools down the combustion chamber enough to provide an actual performance benefit over petrol/gasoline, even though absolutely everything else about E85 should make your car less powerful. Also ram air intakes need to be very carefully designed to get a decent amount of more air forced into the intake. On modern cars it's easier (and less aerodynamically problematic) to use intake manifold resonaces to achieve a similar amount of extra manifold pressure. Even then you'll be looking at maybe 15% more air which is speed dependent and a nuisance to manage on a car without some sort of system to monitor and adjust the AFR constantly, like say, an EFI system. You could also go the old plane route and add a lever or dial in the interior to let you adjust AFR on the fly, which could make it work. Probably doable somehow with some cables and whatnot going through the firewall and looking like a tripwire inside the car lol. The carb spacer is also a bad idea on principle alone. You want as short of a distance between the throttle and intake valve as possible to reduce the distance of vacuum between the two to reduce pumping losses. It's why things like ITB's exist. They won't make any more power than a good intake plenum, usually, but they improve throttle response for that reason. There's a reason BMW dumped a whole lot of money and time into developing valvetronic. Having the intake valves be the throttle bodies themselves does a whole lot for throttle response.

07:12 - Hahaha yeah, I suffered 'Carb Icing' once. Many years a go I had a 1991 VW Polo Classic 1.3 Litre (2 door saloon). I had removed the large circular metal air filter & housing (the design that had a 'Summer/Winter' flap that would allow heat to be directed up through to the air filter housing for warm air to stop the carb feezing in winter), and had installed a home made sponge air filter... ALL WAS FINE in the summer months (could hear the induction roar sound nicely too 😏😉), but, one time during a cold November night driving home from a girlfirends place, the car suddenly coughed and died miles from home. I though "FAAAAK! How am I gonna get home!?" Anyhew, checked under the bonnet, nothing seemed out of place, tried starting the car again and, hey presto! She started! And so, gingerly drove her home expecting a total breakdown... Well, this happened a few times, and after some research I was starting to get a few ideas (fueling? Blockage? Carb Icing?) until one night, torch and screwdriver at hand, I was ready for it. Yup, she died, so I quickly pulled over, popped the bonnet (hood - for you guys lol), unscrewed my DIY air filter, and yup! There it was... FROZEN FUEL in the top of the carb! Hahaha. Being a biker too I felt such a dope as I SHOULD have recognised this from the start! hahaha. So, I swapped back to the original filter & housing for winter, then back to the DIY foam one for Summer. Ohhh what a numpty eh? Hahaha 😉 Sadly, I miss that car 😟, it's one of a few that I SHOULD have kept... 😎🇬🇧

"Nested" intake and exhaust manifolds on inline engines was common from the early 1900's untill fuel injection and multi valve crossflow heads became more mainstream.

I drive an air cooled VW and I swear I don't think my carburetor is any bigger that the ones you've been using. So now you got me thinking...

The carb on my parent's early 80's Ford LTD Station Wagon was a variable venturi carb, too. From what I remember, my father said it worked really well really liked it. His only complaint was at the time, it wasn't rebuildable. So, when it was time for a rebuild, he ended up having to replace it instead. Really neat design: Good power, good fuel economy, and minimal maintenance.

Ram air is doing exactly what it should do

5:26 Treee Fiddy! Dat got dam Loch Ness monster..

the tinyest tires are 125/80R15 who are use on Citroën 2cv...But the best quality (Michelin) tires this size are very expansive (91€ for ONE tire in France).Carb pipes heater are relative similar to the VW on the 2cv flat twin air cooled engine...

i must say I appreciate the amount of effort you put in. and also the metric conversions, they help me out alot!😊

My wife says she enjoys the fuel economy runs because she gets to see a part of Kansas.

09:38 - For the 'Ram Air' to work more effectively, you'd have to install some form of fuel injection system setup, driven by a seperate 'Stand alone' ECU with various sensors to monitor and adjust fueling to suit the increasing air flow the faster you drove. It CAN be done, but, it's not cheap as, well, you'd have to buy the gear, install it, and then book the car in for a coupla runs on a Dyno to tune it correctly & effectivly... So... Sadly a little too much for this kind of project. Though yeah, it would be intriguing how that route would go with regards to power & economy. 🤔 😎🇬🇧

In my experience with tuning cars, fuel ratio is only half of the equation. The perfect (stoichiometric) ratio is 14.7:1 at this ratio you get the most efficient burn. The other half of it is ignition timing you want the timing to be advanced to the point the motor creates the most power as possible then take a degree or so out for safety. The more power the motor makes the less throttle and fuel you need to supply to get the same results. Don’t know if you’ll read this or not but hope it gets to you and possibly help :) awesome project

Driving around on a 100 degree day in my girlfriends Austin America the engine suddenly died. I got out and opened the hood to find that the carb(constant velocity) was a large block of ice. I chipped some away and as soon as it was mostly thawed I discovered that the heater band that was wrapped around the top had the wire broken off. I thought it only worked to warm it up during cold weather. Apparently that particular carb was very efficient at vaporizing the fuel. No wonder it got a solid 35mpg all of the time. Hooked the wire back and away we went !

Smokey Yunick developed the Hot Vapor Engine back in the 1980's ,he used the waste exhaust heat to preheat the fuel charge so the fuel was fully vaporized before entering the cylinder and got 50+ MPG out of the awful Iron Duke 4 cylinder engine made by General Motors.

Im looking forward to seeing how the CVK carb works!

On the ram air idea, there is a difference in pressure between the fuel in the float bowl and the air in the intake pipe. If you connect the float bowl vent to the intake, I'll bet the mixture will be more stable. Rotax used to use this trick to their advantage in the 90s to tune their carbureted snowmobiles for higher altitudes. It was called a H.A.C. or high altitude compensator. Early versions used some kind of mechanical vacuum regulator, but later versions used a solenoid to regulate the negative pressure on the float bowl.

The "work" you've done on various cars has always looked so fun. If I was your neighbor I'd be over at your garage so often, you'd probably get a restraining order against me. Oh, and I love the shots of those blue skies and green vistas. 😃

I had variable venturi carbs (with diaphragms) when I owned a 1980 R80/7 BMW motorcycle. One carb each side (one for each cylinder). Yeah, they were pretty good.

excellent testing

Garage 54 did a test when they did heat up the fuel to its boiling point and did get almost 2/3 the mileage as with the ambient temp fuel. Sure, the test subject was fuel injected. Our old moskvitch 412 had also problems when it was below freezing. It also had a pipe connected from the exhaust manifold to the air filter. On summer, many drivers(my Dad also) disconnected the pipe to get better performance and mileage. But in autumn, if you forgot to connect the pipe back, then you where sitting beside the road waiting to the carb to heatsoak a bit and drive forward few km/miles if you did nod had the pipe with you.

The basic rule of thumb when experimenting is to concentrate on one thing at a time, otherwise it's easy to get lost. You are talented and it's fun to follow the channel. Thank you

You have to have the carb vents in the ram air tube to keep the float chamber pressure the same as the ram air.

Excellent work. Now I look forward to Sundays.

Man i really like all your vids, they're very technical and illustrative, thanks for taking the time to do what most of us wanted to but can't, appreciate it budd

Your channel is one reason why I LOVE Sunday mornings!

Thank you for your time and effort, this is quickly becoming my favorite weekly show.

This is some fascinating testing in the real world very well explained and carried out.

Your videos have become a sunday tradition for me, keep up the good work!

Intro music!!! I miss the Season 1 intro music. It was short, not too serious, and delivered good vibes.

Worked on air cooled engines for many years as a Porsche tech up in Dallas. Almost every carburated motor I worked on had down draft mikuni or weber. Individual runner for each cylinder, not very long runner either. How about a set of regular mikuni carbs on short manifolds for each cylinder? Those long, bendy manifolds are not helping peak power for sure. Call me crazy but I always enjoyed syncing up the carbs. 3 barrel down draft weber on each side. Great fun.

This is the most interesting experimental engineering channel out there imo. It’s crap like this, that I want to work with daily.

These projects are always entertaining.

about jumped out of my chair w/ excitement when you mentioned you would be giving us at least one last video with the saturn. that little thing is one of the coolest cars on youtube IMO

This is the absolute best way to start off a Sunday morning! 👍🏼

Thanks for another great video.

I have found your voice double, even the manner of speech is the same! While watching coverage of the California hurricane a weather guy came on named Josh Breslow who works for FOX Now. Pretty amazing. The car is coming along well 👍

Best videos on Sundays!

BMW used these CV carbs on their Airhead boxer engine bikes from the 70's and 80's. The carbs were made by BING. I have two on my bike and the carbs are fiddly, but work well when they are dialed in. Throttle response is slower by my experience to traditional carbs.

This is just what I needed a great video to relax and enjoy thank you for sharing buddy hope you have a great day

Hey Jimbo, back for more like all the others here. Just a great Sunday vid, thanks man! 👍💪✌

Enjoy your show, keep up the good work

Great as always!!

You sir are living the dream! Love your channel. Hi from Australia 🇦🇺

I look forward to Sundays for my robot fix….

When I built my first 4-stroke motorized bike I added an aftermarket "free flow" air filter because it looked cool. It ran like absolute crap until one day I decided to put the stock air filter back on. It has run like a swiss watch since that day. DERP on me.

Tuned out for a while because I've been busy in life. But coming back to a RobotCantina video is like coming home. Love the content mate!

Brilliant...keep'em coming!!

Thanks Jimbo for another cutting edge tech update delving deeply into the world of D&D (Dittle and Develope). 😂 I wonder if Albert Einstein started this way? You might want to consider a fuel flow meter, coupled with road speed to yield an instant mpg at whatever steady state speed seems best, just to save huge amounts of time. Of course, then other factors start to weigh heavily, such as air temperature, humidity, tire pressure, wind speed & direction, windows open/shut, and road smoothness & grade. Those variable venturi carbs have been used on motor cycles since the late 1980's. With the fuel/air mixture going all over the place, exhaust gas temperature would be a nice parameter to know. I don't know how much extra effort/expense these ideas would add, just some thoughts. Combustion temps peak out at about 15:1, so 18:1 may be okay.

This car is a beast.

Can't wait for that carburator upgrade, your dedication to the science is admirable. It's always easier on paper.

Got me so excited for the next video!

This content strokes the best part of my ADD brain. Ive been watching for a long time and always look forward to your posts every week.

I love listening to that CVT change ratios

Thanks for another fun video y'all! It's quite fascinating watching all the experimenting. Many folk today have absolutely no clue how challenging it can be to tune a carb. Let alone an I4 sportbike. I am so grateful I grew up during the end of the analog days and into the digital days. Being able to tune a carb and yet use a laptop to adjust A/F mixtures is knowledge not too many have.

Good video, thanks for sharing 👍.

Tuned in a little late, but I certainly can't wait to see what the diesel engine goes into. I really enjoy these videos, and appreciate the work you put it.

Uncle Tony just learned about heating the intake on his slant 6 race car. It was causing stutter while doing 1/4 mile passes. Drove him nuts.

Very unique and enjoyable content!

I love this guy. I think everyone who works on engines should watch this as its valuable information.

This was another great video. I am looking forward to more on both this and the saturn. I like diesel engines so the saturn really peaks my interest.

The discussion about warm air intake reminds me of the "thermac"/thermal air cleaner/exhaust manifold heat shroud on a ton of GM cars from the late 60s and 70s. There was a vacuum modulating thermostat and a vacuum operated solenoid connected to a door on the air cleaner. The air cleaner had a normal under hood or front grille intake, and *also* an intake that connected to a flexible hose and shroud around the exhaust manifold. You can find some excellent 1960s service training videos from Chevy that explain this system in detail - it would blend the air intakes to target a 125°F intake temperature in all conditions. If I remember from the original EPA documents, this system reduced cold start carbon monoxide by *ninety* percent! That's a huge improvement on top of driveability and efficiency improvements.

We love the channel and the projects you are working on. Love Love Love the Saturn car wonderful design and execution of the Diesel engine happy some parts will get a second life. Thanks

Just drove my 2002 ford focus wagon with 285k miles on it to the junkyard 150 miles away in 3rd gear on local roads . Tranny shot they gave me 175 dollars for it delivered . A guy picked me up at the junkyard in his 2000 Honda insight manual transmission car as a test drive . I bought it, had to, no way to get home! I seems to run fine and gets great Milage . When the engine goes who knows what I will put in it….

I love this channel and this kind of experimentation! I look forward to each one of these videos, and I recon I ain't the only one. Looks like we are still in Kansas Toto. click click.

Hey Sir, i have a gnarly suggestion. Being that the Saturn is a Metro and a Metro is Toyota based and it's 850 lbs lighter than a Tercel (made from Pvc, fiberglass, polymer and recycled refrigerator doors. Convert the SL2 into a quasi hybrid meaning Prius electrical mixed with Predator vtwin. GNARLY for sure.

❤thanks again guys🎉