MAX Update No. 26: Seeking Ideas for More Horsepower

| 3/26/2009 12:16:31 AM

Tags: MAX, Auto X Prize, 100 mpg, horesepower, acceleration, gas mileage,

The rules for the Progressive Insurance Automotive X Prize have been under development for some years now, and all us entrants are on pins and needles — waiting for their release. We've had looks at rule proposals all along the way, given to us in confidence. That's really been the only challenge I've faced as a combination entrant/journalist: there have been times I've had burn-after-reading documents and had to resist my urge to blab.

But now that the latest draft of the Auto X Prize Competition Guidelines have been made available to the public, I'm going to ask for your advice.

The final rules are pretty certain to require we meet a performance standard of zero to 60 mph in under 18 seconds. Not much under, 17.999 will do, but for MAX, that's going to be tough.

What? 18 seconds to 60 mph isn't very fast, but you'd be surprised how many vehicles on the road can't do it. Fully loaded, my four-cylinder Dodge Caravan can't do it, and while it's hardly a performance car, it's adequate. Anyway, this 18 second thing is a fairly recent requirement. It wasn't in the projections when we signed up, so we had designed MAX from the get-go to hit 60 mph in 20 seconds.

Why 20 seconds? Because that's in keeping with the low budget sports cars you could buy new when I was young (and quicker than some, such as the Bugeye Sprites and the Karman Ghias) and I thought it could be done today with a 100-mpg, low-budget sports car. I'll confess we haven't hit 60 mph in 20 seconds yet. On paper it looks like streamlining will get us down to that, so I'm not worried. Or I wasn't before … but I am now.

To increase acceleration to a given speed by 10 percent (in this case, from 20 seconds to 18 seconds) requires more than 20 percent more horsepower. To skim over the math, it would take 10 percent more thrust applied for the same length of time, but by definition it has to be accomplished in 10 percent less time.

jack mccornack
9/8/2010 7:38:58 AM

Thank you all for these thoughtful and inspirational comments. I'm going to try implementing some of these ideas when I get back from the MEN Fair late this month. I'll be making my choices based on cheap, light, harmless, and finally, whether they seem likely to work or not. But first I'm going to take MAX up to Washington State and get a smog check. I want to have a base line before I start messing with the motor. I haven't had success getting a smog check here in Southern Oregon, the state sets the fee at $10 (which ain't much) so nobody's real excited about testing a vehicle that doesn't require testing. But I want to know, so I can re-test after any engine mods and see that I haven't made emissions any worse. For example, resetting the governor to a higher RPM limit meets the cheap (free, actually) and light (no weight change at all) and will almost certainly increase power, but what will it do for NoX? I won't know unless I test first, make the change, and try it again. Ditto turbo adjustments. The only mod I believe is guaranteed to meet all my requirements is... Well, could the pilot be lightened? :) ...and Tom, that is such a great idea that I got right on it, and have shed a whopping 40 pounds since your comment hit the blog.

billy clark
9/7/2010 12:12:16 PM

Generally speaking, diesel tractor engines are easliy capible of additional horsepower as they stand. If you do a little checking you'll likely find that the exact same engine you're using comes in a range of horsepower configurations. Also, generally speaking a diesel gets BETTER, yes that's right, better fuel economy with increases in power, or fueling rates. My experience with large diesel engines has shown an easy 10% increase in economy with a 10-20% increase in fuel and a slight bump in timing. With more at the beck and call the engine calls for it and gets to it's target speed and backs off rather than puffing along for miles trying to get topped out. My '99 Dodge/Cummins will get 24mpg highway with a 50 hp increase via a computer flash/programming change. It comes rated at 215 hp in the stock truck, but the EXACT SAME ENGINE can be found making up to 400 hp in other applications So, do you have a manual injector pump, or an electronic one? It just determines whether you need to turn some screws, or find a way to "tweak" the programming. Most everything is electronic nowadays with all the emissions requirements and such. Hey, give it a shot. If the fuel mileage suffers you can always set it back to stock, but I'm betting you will be pleased with the results all the way around.

christina ward_2
8/26/2009 12:02:56 PM

There are alot of really good ideas, here. The first thing that came to my mind was the addition of the hydrogen generator (water is cheaper than gas!). Hydrogen would give you that extra boost with either a gas or diesel powered engine combo. I don't think it'd be so great with an electric generation system,though. I'm only an intermediate "gear head", not a pro by any means. I hear the Hydrogen system actually will increase your mpg a great deal. Good Luck, Jack!!! Christi

8/2/2009 5:58:17 PM

Lighten the car and keep streamlining. I thought about suggesting gear and rear end ratios but have to discount that idea because your argument for horsepower overrides. Herb Adams in his book "Chassis Engineering" suggests making every rotating part as light as possible. There is a nice chart showing the possible gains. This means gears, flywheel, driveshaft, axles, brake disks and/or drums, wheels and tires (including the front).

jason phillips
7/31/2009 10:39:12 PM

More boost via compound turbocharging. Meaning a larger turbo feeding air to a normally-sized turbo that then feeds the engine. Forget intercooling as this will hurt fuel economy in a diesel and it'll make an already-complex system even more so. I have a SAE paper addressing the intercooling and aftercooling issue somewhere around here.... I'll see if I can locate that for you. Beyond that: you've got a windshield right? That means you likely have a windshield WIPER....right? And THAT means a windshield WASHER would only make sense. So what about using all that stuff to inject a little windshield washer fluid into the intake during full-throttle conditions ONLY. Use a pump, fluid, and reservoir you already have for a different purpose. A simple on/off switch under the accelerator pedal should do the trick. Alternatively, have the water/methanol injection tied to turbo boost like the M. Goudard device (patent no. 2,290,610) illustrated on page 133 of "Turbochargers" by Hugh MacInnes, the Dick Griffin system shown on page 135, or the system developed by M&W Gear Company of Gibson City, IL shown on page 137 of the same book. No electric pump and no added wiring. (I'm a big fan of the K.I.S.S. principle whenever applicable.)

5/2/2009 8:46:15 AM

Tractor engines are built to go slow and last decades, not go fast efficiently. To accomplish this, they build them big, heavy, and underpowered. I rejected Kubota engines for my project because the of their power to weight ratio. I recommend looking into Isuzu diesel engines. I believe you can find similar horse power in a much smaller, lighter package.

mike lutz
4/6/2009 10:10:40 AM

i would start with a hydrogen set up

tom whitehead
4/5/2009 8:53:47 PM

hi Jack, I think using a propane injection system could be cheap and effective. You only need the propane for when you're trying to pass the test. So I would hook up a barbecue bottle, and an adjustable regulator. If you hooked a couple of springs up to your throttle, you could make a two-stage throttle. The first stage would be your normal engine control, no propane. After you've bottomed out on that, you would press a little further and make contact with the gas solenoid switches. You could use two or even three. So the first switch opens up and shoots a metered jet of propane into the manifold. Push a little harder, and open the second switch. That would open a similar solenoid, so now you'd be running 2 jets of propane. And the third would act similarly. so the whole thing would probably cost you less than a hundred bucks. Give me an e-mail if you need any solenoid valves, I'm not sure if I have any in 12 V, but I know I have some bodies. Best wishes, Tom

4/4/2009 12:27:05 PM

Howdy Jack! I love this project- been following your progress since the beginning... Lot's of good ideas presented already, just tossing in an easy one- electric cooling fan as opposed to the standard belt driven critter. The HP return on this isn't all that big, but combined with some of the other efficiency ideas (reducing friction, cold air intake, etc) you probally can "steal back" enough HP to hit your goal. Just like living with alternative energy sources, there is not a single magic bullet. The sum total of efficiency improvements will get you (and hopefully soon the rest of us) where we are going. Thanks for the project- you've inspired a lot of grass roots projects out here.

jeremy wyatt_2
4/4/2009 11:25:51 AM

Several posters have gone down the same logical path. I believe you want to focus on a means of storing energy for launches rather than worrying about trying to find the extra power in the engine directly. Improved lubrication is always good but your friction losses are probably in the range of 1.5kW to 2kW. Amsoil for instance claims about an 8.2% improvement in friction losses for a diesel engine. So you might recover .34 HP at best from better lubrication. Increasing fuel pressure will increase fuel consumption so that is likely to hurt the 100 MPG target. For the same reason, other engine modifications should be carefully considered. One direction to consider here though is the camshaft design. If you can get some help from a university with an automotive engineering program, a camshaft designed for your power-band requirements could be promising. To overcome the inertia, some means of storing energy seems most likely to succeed. Electric is an obvious approach but will add significant weight and complexity. Using nitrous or propane may be very effective but conceptually undesirable since the objective is to create a practical design. Any vehicle that requires the operator to manage multiple fuel sources is probably not going to appeal to anyone other than us gear-heads. I would suggest looking at a flywheel storage approach. The following article might interest you: Good luck!

4/4/2009 1:58:06 AM

Check out the onboard generator that adds a small amount of hydrogen to a gas or diesel fueled engine prompting a cleaner, more efficient combustion. Is right up your alley as it can be home built for easily under $175, is small and is light weight. Talk directly to Ozzie @ and I am sure he'd be glad to help. Or think way out of the box and change the world by Switching engines over to the non-polluting Aerodynamic Air Turbine Engine (AATE) as shown via the developers site: This nation, economy, environment, our children and future generations will greatly benefit from what you can do. Keep up the great job! John B.

robert thomas
4/4/2009 12:54:36 AM

I've followed the development of Max from near the beginning and a mechanical lock up CVT as mentioned earlier is a great idea along with the minimization of internal and rolling friction. After increasing your efficiency using these methods focus on increasing the torque at a specific RPM and you should attain your acceleration goals. The increase in efficiency should also help you MPG goal especially if you have a method for adjusting the CVT while driving.

pat miketinac
4/3/2009 9:18:19 PM

As a former aircraft mech., I have often wondered if a twin engine concept could work in cars. The cruise engine would be just big enough to maintain level speed for max economy. The other engine would be big enough to meet acceleration or climb requirements when both run together. The second engine could be mounted alongside the first connected to it with a supercharger style belt and an electric clutch as used to drive car a/c compressors. Throttles could be linked and fuel and ignition controlled electrically. The first engine could start the second one when the electric clutch was engaged. There may be a better way to do this so you can keep going if either one quits, like aircraft or some hybrids can do.

roger l. osgood
4/3/2009 4:41:27 PM

Put an electric motor in the middle of the drive shaft and add batteries! Lots of electric motors are available! My Locost will be totally electric! with an generator added to charge it when stopped! I am working on it now! If you want to get too fancy, front wheel motors on each wheel will also do it! Roger

4/3/2009 2:43:26 PM

Oh and no need to mess around with adjustable wastegates. A simple bleeder valve will suffice. In fact, I've seen guys use an aquarium valve to bleed off air going to the wastegate. That way the wastegate "sees" less boost than is actually being produced by the turbo. A poor man's boost controller if you will.

4/3/2009 2:40:29 PM

First of all, I think your 25 horses are to be found in the turbo. Changing rear ends, the frame, adding electric motors, is opening up a whole can of worms in my opinion. You've got a turbocharged diesel... focus there. If you're not intercooling then by all means do that first. Giving your engine cooler/denser air makes a huge difference. What are the specs on your turbo? TD04 based? You could swap your turbo for one with a different A/R ratio, compressor, exhaust turbine, housing, etc. Is the turbo for additional power in the lower portion of your power band or higher? I'd confirm that you've properly matched the turbo to the engine and your torque requirements. Then make changes accordingly. If you end up with too big of a tradeoff in low vs. high end power you could consider a sequential turbo system similar to a Mazda RX-7. You could have a quicker spooling turbo for 0-60 (or 0-30 even) and then the second turbo for higher speeds. It'd be a little more piping and additional complexity but just wanted to throw it out there.

4/3/2009 1:39:40 PM

What will work? Hydraulic hybrid addition.If you have any question as to whether it will work, just go to the EPA, Ford, Eaton, web sites devoted to them. Ask UPS, Waste Management, Ford, BMW, etc. whether they work. They work! You can reduce the current engine size because during times of low power need the accumulator will be steadily charging to give the boost you will require for acceleration from stop, accelerating while rolling, and passing. Smaller engine size and more potential energy. We can and must stop the importation of oil from countries which want to kill us. Make this work and put it on the market! I'll buy one! I have been putting off purchasing a new truck for 3 years now. I'm waiting and Detroit keeps going bankrupt producing gas guzzlers. Do you get the feeling that they don't want to save fuel? I certainly do.

4/3/2009 1:32:06 PM

Yes...I KNOW..I Misspelled "Radiator"...Unless you are using a Dyslectic I do

4/3/2009 1:20:36 PM

A few ideas to consider.... "Better" Injectors...(Like the Kubota Engine gives you a lot of options) Higher Fuel Pressure...(Again..Limited Options) Higher Boost Pressure..(combined with Intercooler below A "Non-Convential" Intercooler I read about this in on of the Drag Magazines a few years ago (Hot Rod, Car Craft..etc.) Instead of the standard "Raidator" style of intercooler...A company in SoCal "Re-developed" an Intercooling Method that was used on Turbocharged German Fighter Aircraft during WWII. (Move the Turbo away from the Engine) Run an exaust pipe down the underside of the car to an area just forward of the rear wheels..and install the turbo at that point...the air intake is also moved to the rear (protected from the elements)The Return air to the motor begins as a small pipe and about 1/2 to 1/3rd of the expands into a pipe of at least twice the original diameter (cooling the an air conditioner works..OK)Also the surface area of the return pipe FAR exceeds the surface area of a standard this method takes the the intake air away from the heat of the engine compartment... I know what you are thinking...TURBO LAG+.... but the articles stated that the "Spool-Up" time was equal or LESS than a engine with a standard Turbo/intercooler setup. Last but not least...The "Still Born" Top Gear USA television program took a VW Rabbit Diesel (AKA The Sipster) and were able to "tweek" it to 84mpg with a 0-60 time of 7 SECONDS! May be time to send the Kubota...packing With Electronic Fuel Timing..etc. A 100mpg Locost 7 is in easy reach.

vin dicator
4/3/2009 1:16:17 PM

Make it a hybrid and use the electric motor to get you up to speed that much faster.

4/3/2009 12:51:55 PM

Why don't you see about adding an intercooler? Remember, turbo engines always produce the most HP when the air temp is cool, so run your 0-60 test with a cold motor. You can even pack the air intake runner (outside, of course!) with dry ice to increase air density that increases HP. Open up the air intake, route it where it gets the coolest air, and put the biggest K&N air filter you can fit on it (toss the two stage stock filter designed for ag work). Port and open up the exhaust (ever hear of a dump pipe?). You can increase the boost since you will only increase fuel consumption when your foot is in it. Have your injectors balanced for flow. Be sure to work on your reaction time as well. These are some of the tricks we use on our turbo Buicks. Good luck!

4/3/2009 12:03:38 PM

Dont know if you would get all 20%, but one thing that is common is bearing friction, If you have not done so, check and see if the bearings that you are now using are micro graded, the tolerance on the good bearings that are available do not come close to what is being manufactured today. As an example, one of the things Honda cars have done for many years is use better bearings, if you are old enough to remember the Civic when brought out got 50 MPG, and they lasted forever, and continue to. Another example that I delt with is heavy equipment, the reason that Caterpiller has been so sucessfull is the fact that they use better bearings than others, the resulting lifespan of a Cat is well documented. Again just a suggestion but who knows, Network Thinking YES!

4/3/2009 11:45:39 AM

These all seem to be really good suggestions. 1 that I don't see is the idea of HHO generators mentioned. I have been using an HHO w/electronic modulator and have a Pontiac Montana that's now getting 26-27mpg, and although I have no way of proving it, I feel that I'm getting better response out of it.

doug smith
4/3/2009 11:38:27 AM

Seems to me as though you are trying to do this as environmentally friendly as possible? If so you can rule out the nitrous and Propane. You could inject natural gas made with an environmentally friendly process. Water injection is another idea, but requires an additional tank and weight to overcome. The best and least expensive mode you can start with is bigger intake and exhaust. This is the biggest loss area for most newer vehicles. I liken it to you being restricted to breathing through a straw. Try it sometime it is pretty hard. Those cyclonic air inducers give you better atomization, which would work great on the veggie rig of yours (correct me if I am wrong on your fuel of choice). regearing would be another option that would not be harmful to the environment. I have a friend that lives close to me that has invented a CV transmission that is both durable and efficient. It is not the belt type you see in most cv trannies, it uses two cones with helical gears driven by a computer system (must be automatic). You can look him up it is called the vancor transmission. Can you construct a suitable roll over protection system with aluminum? I agree with the tire mod as well, but I will take it one step further and suggest you research better wheel bearings. Most all os these ideas don't require a major overhaul of max. If you are open to a major overhaul, I might suggest you think like a train and do a Diesel electric hybrid. with that small engine, and those electric motors that fit at each wheel would be nice, and you would not need any transmission. Wow, I have gone on haven't I. Good luck on your project, wish I was there to help!!

terry burns
4/3/2009 11:06:34 AM

Diesels are pretty tough.Check out some drag racing diesels on You Tube. Raise the operating rpm. Use higher rpm for more HP at 0-60, and stick to lower rpm for MPG. I can't remember if you have a turbo or not. If not a turbo will also maybe improve the mpg on a diesel.

4/3/2009 10:16:13 AM

Increase the efficiency of the airflow to the engine, and out of the engine. Air that is spinning cylindrically like a tornado is highly efficient and produces more power. There is an air intake product on the market called the Tornado. Look at it. Adopt this idea for your intake and also at the last foot and a half of your exhaust. Do both of these things and you'll be surprised at the performance gain you achieve. From a retired Space Shuttle Quality Control Inspector.

4/3/2009 9:55:16 AM

Jack, You could add UNIGLIDE to the motor oil. UNIGLIDE is a friction reducing concentrate which may release as much as 10% additional power and it is available in the USA. I drive a '97 BMW 323 (2,5L) which has received the Uniglide treatment. On a dyno the power increase @ 5000r.p.m. was in the order of 8% and fuel consumption improved by 6.5% overall. I have now driven over 50 000kms on Uniglide and if anything the engine is smoother and quieter than ever before. How about Nitrous injection for the acceleration bits only as well? This is a simple set up.

4/3/2009 9:53:59 AM

air induction

4/3/2009 9:43:10 AM

Maybe a change of rear gear ratio and an overdrive/underdrive unit? Also, years ago my Dad have several Model T Fords that were made into homemade tractors. Some of them used two transmissions inline to get the necessary gear reduction. Maybe a taller rear gear ratio with an auxiliary transmission would do the trick, by providing a low, medium and high range similar to the way big rig truck transmissions operate. It would increase off the line torque and performance and still allow for low rpm cruising speeds.

4/2/2009 5:37:02 AM

I agree with using the hub wheel moter in the front wheels for a power assist. This keeps it simple. Also instead of heavy batteries I would go with ultra capasitors. Their light and take regen breaking with great effeciency. If you only need it for acceleration then they will give you plenty of power. Plus they will not need the maintenance or costly replacement every few years. They can virtually last forever. A cool bonus, a major manufacturer with the name of MAXwell makes some. ;)

bill m
4/1/2009 10:57:03 PM

Propane may be the way to go, you could use it for the acceleration runs and then turn it off so that it wouldn't penalize you on mileage.

3/31/2009 12:48:30 AM

I'd suggest finding a wrecked Honda Insight, and using the powertrain from that. It can push my Insight (1850 lbs + about 250 lbs driver & dog) to 60 mph in about 10 seconds, so should be able to do better with the lighter MAX. Even if you don't want to use the hybrid part, the IC engine is about the lightest you'll find, so should knock off a bit of weight. Also has the best fuel economy - I've gotten 70.9 mpg average over almost 6 years & 85K miles of mostly mountain driving. You might also look at the Insight's lightweight wheels and low rolling resistance tires. As I'm sure you know, the wheels are the hardest part to accelerate, because they have rotational inertia in addition to weight.

mark wintermute
3/30/2009 5:22:05 PM

Your 35HP diesel allows CVT possibilities that are challenging to larger motors. Look at or better yet contact them and see if they would modify or create a CVT specific to Max. This would also give everybody a source for the transmission rather than looking for a salvage donor. I also like the idea of a centrifical clutch that would allow free wheeling of the engine. You lose engine braking but you can roll forever. Mark Wintermute

3/29/2009 12:11:52 AM

I seem to recall Jack saying something like "for a million dollars we could be 25% better..." and I hope we're not there yet. So besides all the good suggestions above hopefully one of these might get you a couple horsepower or lower some weight or rolling resistance: - can you "port" the intake manifold? - perhaps you could you use an "underdrive pulley" on the alternator? - perhaps an "absorbed glass mat" light weight "racing" battery? - lower rolling resistance tires? possibly thinner tires? - lighter weight (magnesium?) wheels? - You might also consider reducing the fuel tank size and load for the competition. (what range do you need?) regarding the gear ratios, from your articles it seemed like first was lower than needed. Would it make sense to optimize 1st, 2nd, and 3rd to a fairly "close ratio" (assuming you can reach 60 in third while near peak torque ) and have 4th a real "tall" gear for cruising and highway mileage? one less shift to 60 mph?

john adams_2
3/28/2009 11:34:54 AM

Well, Propane will add to the performance of a Diesel (check the drag racing sites on the WWW). Additional boost from the turbo will help but will use more fuel because in order to make more power an engine must use more fuel. Adding an electric assist could be cool, since it will be a hybrid, but you'll have to lug those batteries and controller around. How about this: Attach a pump to the drive shaft or axle. Connect it so that when you press on the brake the pump forces fluid into an accumulator - See link( ) . Then when it is time to accelerate again, the accumulator pushed the fluid back into the pump (causing it to become a motor) and returning some of the energy stored from braking and using it for acceleration. Maybe not as Ueber-tech as an electric system, but it's pretty simple. Yes there is a pump and hoses, fluid, and the accumulator, but I may end up weighing less that a similarly capable electric system.

bas doeksen
3/28/2009 5:31:15 AM

Having looked at the performance curves at it seems to me there is some room for higher power beyond 3000 rpm. Replacing the spring in the governor as Kimer6 at the ecomodder forum has done seems to be the easiest modification. It's not bad for the driving experience either.

frederick sullivan_2
3/26/2009 8:40:58 PM

Jack, how about a.aluminum frame b.higher rear axle for quick acceleration combined with higher overdrive trans say a 6 speed from a newer mazda miata.c.4 cyl Kubota turbodiesel with same on lower rear( from what I've read thats what honda did on their civic diesel 2.2L or 2.5L and it improve mpg). d. do they still make external overdrive units?

frederick sullivan_2
3/26/2009 8:39:38 PM

Jack, how about a.aluminum frame b.higher rear axle for quick acceleration combined with higher overdrive trans say a 6 speed from a newer mazda miata.c.4 cyl Kubota turbodiesel with same on lower rear( from what I've read thats what honda did on their civic diesel 2.2L or 2.5L and it improve mpg). d. do they still make external overdrive units?

3/26/2009 2:54:26 PM

Jack -- Is the fuel system mechanical or electronic? If you have, or can get an electronically controlled common-rail injection system, you could more than likely tune your way to sufficient HP with the existing engine. And with your laptop on board, you could change fueling pulse, frequency and duration on the fly to suit your needs. I really think you might get all you need from increasing boost and exhaust modifications. Does your induction system include an intercooler? They aren't that difficult to fabricate from a suitably sized radiator. How do you feel a bout the induction system's geometry? Is it as efficient as it can be? You might check with the folks at Banks Power: or Bully Dog: for ideas and sponsorship. Bully Dog already has some tractor tuning modules and the engineering side of Gale Banks' organization is all about diesel performance.

tim nelin
3/26/2009 11:35:31 AM

Effective ways to gain power from a diesel engine are 1)-increase turbo boost (waste gate adjustment or replace turbo) 2) increase size of exhaust tubing 3) Adjust injection pump for optimal advance and fuel delivery for application 4)-replace camshaft with one ground for more performance. The best part is that most modifications won't affect mileage to ant great extent! Great project, very inspiring!

3/26/2009 9:09:11 AM

Apparently, nitrous injection systems work very well in diesels. Propane systems also seem to work well and promise more power and better gas mileage and better emissions when used with regular diesel fuel. Happy motoring!

jack mccornack
3/26/2009 9:09:08 AM

Man, I can see I brought my question to the right crowd! Great ideas, folks, and don't stop there! I'll give every one of them some serious though. Okay, except for the rocket assist idea. Rockets are notoriously poor performers on emissions tests. :-)

3/26/2009 8:48:27 AM

Perhaps you can use a nitrous system on a diesel???

3/26/2009 8:37:30 AM

Perhaps a lower rear end ratio. Or a tighter gearbox. What parts of a Kubota turbodiesel are driven off of a belt or belts? Can these be replaced with electric motors? Is the turbo optimally placed? Can the intake air be cooled further? Does it need a different cam? Can you use lighter pistons, different valves? Can you use a dry sump system? Synthetic oil? Can you rebuild the engine? Is the fuel injection system optimal? Can you retrofit a direct injection system? Can you use a bigger engine and shut off fuel to cylinders when you don't need them? Dare you go hybrid with a 8 hp DC electric motor and associated batteries , controller, charger etc.? Would an available CVT be any help? I would call Kubota and see if they can be any help. I would check out tractor pullers like Tom suggested. They are all about diesels and acceleration. Be aggressive as you can with aero. If I can see your rear wheels, I'll know you're leaving money on the table. Perhaps a flywheel?? Good luck and happy motoring!

bas doeksen
3/26/2009 7:51:56 AM

Disabling the rev limiter would be great, but would only help if the added rev range (above 3000 rpm) would yield enough power (i.e. if the maximum torque does not drop too much). Other options: -Use a supercharger (bad for your fuel economy) -Add an electric motor. For example the Mars PM motor has plenty of power (around 10 kW peak) and weighs only 26 lbs. Retail price is $450 at Thunderstruck EV or Kelly controllers. It might be difficult mechanically to couple to the crankshaft though. An easier construction would be to use hub motors (as used for electric scooters) in the front wheels (10-15 kg each). That would be good for regenerative braking as well. You can get about 30 Nm of torque per motor, which translates to about 210 N of forward force on Miata wheels (15/195/50), giving a 1500 lbs vehicle an extra boost of 20 km/h in 18 seconds. You would need something like a 48V/20 Ah battery, speed controller for the motor and a DC/DC converter to keep that battery charged. It's all a bit complicated and not really in the Locost spirit. -Solid fuel rocket boosters. Do the rules specify how often you have to be able to accelerate to 60 mph in 18 seconds? ;-) Bas.

3/26/2009 1:24:22 AM

Well, could the pilot be lightened? :) I can only wonder if the turbo could be adjusted for a little more boost, and if you could disable the rev limiter. maybe you could get a couple hundred more rpms (not a diesel specialist, but had a vw one and it would rev). I ran across this dealer while googling for you, it came from a tractor pulling site. They have a turbo with adjustable waste gates for the Kubota RTV900 www dot swaginc dot com Good luck, anxious to see the top you have designed.

dairy goat


Aug. 5-6, 2017
Albany, Ore.

Discover a dazzling array of workshops and lectures designed to get you further down the path to independence and self-reliance.