Tiny engine, insane power

[goldie]

Hello there!

I know that for most of you this sounds ridiculous but-..
I have a Renault Clio 3, 1.2l 16v 75hp aspirated. The car that I learnt how to drive in and had so much fun driving because of how nimble and fast it feels. Didn't get this sensation in 150hp cars.

I want to start an unique project, modifying this car to insane powers.
Let's set things straight. I don't care about fuel consumption (it will most probably run on ethanol or other race fuels anyway), it won't be street-legal and yes, I do have the money required to get into this. Not F1 budget, but enough to make this project come to reality.
I know that the whole car will need to be modified. Brake system, transmission, clutch, whole engine (the whole point of it is that I'll keep the 1.2l engine, same design, but rebuild everything, stronger block, forged internals, etc..), even the chassis.
Unfortunately I'm not that experienced in technical stuff. I want to modify it myself as much as I possibly can, but I know that the engine and other parts will need to be rebuilt by professionals, costing a lot of money.

The goal of this thread is to help me understand the basics of what will need to be modified and the process of it. What fuels would be better suited for this, supercharger or turbocharger, what needs to be done on the inside, transmission, exhaust, etc..
My (unrealistic and probably not even possible) goal is 750hp (10x). A more reasonable goal will be around 400-500hp.
There are already cars that achieved numbers like these. An Audi A4 making 400hp, Seat Ibiza 300hp / 350hp+, VW Lupo 250hp+, etc.. so IT IS possible.

Hope you all have a great day, a great new year and thank you.

 

[obi_waynne]

Anything over 240hp and realistically around 200hp will struggle on a FWD setup, there is just no way to get the power down, so AWD or 4WD or RWD conversion would be a must over this.

Part of the fun is the lightness of the engine block itself, higher powered engines are much heavier so don't feel quite as nimble.

I'll have a think and post more thoughts later on when I get some spare time.

 

[goldie]

Anything over 240hp and realistically around 200hp will struggle on a FWD setup, there is just no way to get the power down, so AWD or 4WD or RWD conversion would be a must over this.

Part of the fun is the lightness of the engine block itself, higher powered engines are much heavier so don't feel quite as nimble.

I'll have a think and post more thoughts later on when I get some spare time.

I was thinking about an awd conversion and personally I thought I'd get an A3 quattro system and try to fit it on the car, since the A3 is the closest to the clio when talking about size, but would a 1.2, even if I get it to 240hp+, be able to handle turning 2 more wheels?

About the engine block, what material should it be made from? Right now it's purely my curiosity because when it comes to the engine I'll send it to a shop, I'm not qualified enough neither have the tools to rebuild a block.

 

[SLEEPER]

Now I am all for doing crazy engine builds but i am afraid your aims are just too optomistic.
First 750 just wont happen with 1.2 litres and I cant see 500 or even 400.

The limiting factor is air flow not materials - If you stick with a normal production 1.2 engine it just wont physiocally flow enough air and that doesnt just limit the power it determines it .
And once you get anywhere near the theoretical limit of an engine each percentage gets way moe difficult.
If you are serious and cost isnt an issue then get a 172 engine then you can reach your lower figures for sure because it is 2 litre with a very good head design.

 

[goldie]

Now I am all for doing crazy engine builds but i am afraid your aims are just too optomistic.
First 750 just wont happen with 1.2 litres and I cant see 500 or even 400.

The limiting factor is air flow not materials - If you stick with a normal production 1.2 engine it just wont physiocally flow enough air and that doesnt just limit the power it determines it .
And once you get anywhere near the theoretical limit of an engine each percentage gets way moe difficult.
If you are serious and cost isnt an issue then get a 172 engine then you can reach your lower figures for sure because it is 2 litre with a very good head design.

As said, 750 is just a 'dream' right now. I'm sure a 1.2l engine can reach that, but only with F1 level budgets, which I don't obviously have. Though, seeing 300-400+hp 1.2l builds on the internet, not made by teams with huge budgets, felt like that's a more reasonable power.

I don't really want to switch to another engine mainly because the whole 'magic' of this crazy build is for people to say 'nah stop joking, tell me what engine you really have' when you tell them the horsepower.

The engine will have to be modified anyway, new block and all that. Maybe it can be modified to allow more airflow and be able to achieve those powers, while still keeping the 1.2l capacity?

 

[Druidoak60]

Turbo would be the way to go, supercharger would be to much of a parasitic draw on that small of an engine. Your going to need a forged bottom end, also see if the engine can be bored to a larger size, bigger bores would help a lot. Fully ported heads, bigger valves, better cam shaft. Bigger valves, meth injection and nitrous oxide.

 

[Fabia17]

As said, 750 is just a 'dream' right now. I'm sure a 1.2l engine can reach that, but only with F1 level budgets, which I don't obviously have. Though, seeing 300-400+hp 1.2l builds on the internet, not made by teams with huge budgets, felt like that's a more reasonable power.

I don't really want to switch to another engine mainly because the whole 'magic' of this crazy build is for people to say 'nah stop joking, tell me what engine you really have' when you tell them the horsepower.

The engine will have to be modified anyway, new block and all that. Maybe it can be modified to allow more airflow and be able to achieve those powers, while still keeping the 1.2l capacity?

Hi, I get where you are coming from and understand your ideas. I'm a small engine big hp nutter to. I run a street legal 1.2tsi Skoda Fabia Monte Carlo Estate, which is currently running at 160hp.

However you are failing to see the fundamentals, especially with what @SLEEPER says.

A 1200cc engine is just that, no more, no less, so air flow will always be 1200cc, there is this thing called swept volume but for simplicity we'll just call it 1200cc.

You can improve air flow, by modifying intakes etc, but it is still 1200cc

You can increase the amount of charge you can squeeze into each cylinder but using a supercharger or turbo, or both, but it's still only 1200cc.

Changing up fuels helps you extract more energy per power stroke, but it's still only 1200cc.

So there is a point at which the laws of physics will determine how much power you can extract from 1200cc because there is a finite amount of energy available in each power stroke.

All you can do is to spend your money on extracting as much power from each power stroke and no more.

It's a numbers game.

I don't think it's unreasonable to expect 250hp from a highly modified 1200. I have a hybrid turbo lined up, which is a bolt on that will put me just top side of 200hp on my Skoda engine. And that's with no internal mods.

I have not sat down and worked out the theoretical max hp from 1200cc, but you can.

My suggestion to you, is to spend some of the money burning a hole in your pocket on college, and learn the fundamentals of motor vehicle engineering. It's vital if you want to move forward successfully.

If you can afford to start having blocks manufactured from billet, along with cranks, rods, pistons and heads, you are in a very priveliged position, and if I were there, I would contact a company in the UK called Millington Race Engines (if memory serves) they design and build race engines, not modify, but manufacturer their own engine. Not that expensive either at around £20000 which is what you would easily spend bashing a stock 1200cc motor into shape.

I don't think you have thought any of this through at all. I have been in the industry most of my life and carried out some serious engineering works. But chasing mega figures from small engines is a fun game but comes at huge expense. Least of all in the motor.

I applaud your enthusiasm and I admire your budget, I certainly wish I had an almost bottomless pit into which to dip. I have just ploughed through £10000 in less than 9 months on my persuit for small engine power, most has gone on brakes, chassis and suspension. The motor always comes last but alas the coffers are almost depleted now.... But 200hp is easily doable on another £2500.

So my friend you see, money goes absolutely nowhere, especially when you are paying other people to do the work. I have to these days due to serious health problems, £50/hour to £200/hour is what to expect when you hire good people.

Sit down, learn, then learn some more. Then spend wisely. If you want 500hp+ then you need to work very hard. And probably look at a 1.4 or 1.5 (2.0l would not be a huge challenge but would be more reliable) reliability is another important subject... You might squeeze 300 or 350 hp from a 1.2 but will it be drivable, or reliable? I doubt it. It might last a dozen runs on a dyno, or the strip but you'd be forever rebuilding it.

Good luck.

 

[TCJBOLDIE]

IIRC The 4 cylinder BMW F1 qualifying motors put out something like 1500hp but the race motor app 800hp.

BMW M12 - Wikipedia

en.wikipedia.org

 

[Fabia17]

IIRC The 4 cylinder BMW F1 qualifying motors put out something like 1500hp but the race motor app 800hp.

https://en.wikipedia.org/wiki|BMW_M12

This is a fine example of what a bottomless pit can create. This is engineering at the cutting edge (at its time) and we still see the F1 engines banging out over 1000hp, but at what experience, and cost.

The engines are stripped and rebuilt after every race with no expense spared towards replacing parts, it's a throw away society at its worst. We could not operate like this.

When I was drag racing back in the 70s we used to strip and rebuild after every event (which would last the day) but the guys next to us in the pits running Nitro rails were rebuilding after every run.... It was crazy money.

I guess it comes do to what you want from the end product? Do you want an engine to be a "let's just see what we can get out of it before it destructs" or is it an engine to drag race, circuit race, or a reliable daily?

The answer to this question will determine what type of engine you build.

If I had another £20000 I would build a mind blowing 1.2, I would expect around 400 to 500 hp but be a road usable engine. But I would need to change all my running gear and transmission, it would have to be four wheel drive. There is no other way to get that much power to the road in such a small car.

I can see what I would need to do, and it's doable. But money is the limiting factor.

Could you squeeze 700hp out, possibly not on a stock block and certainly not with stock anything else.

It would need to be a ground up design imo. I'm not sure a stock block and head would take the punishment but it would be intesting to see how far one would go before it blew the head off or punched out the side..... We may be surprised

 

[goldie]

Getting back to this topic after half a year, hoping that I can start this project in the summer.

The capacity of the engine is 1200cc and as you said, no matter how many modifications you make to it, it cannot get past that capacity. However, one liter of water is less dense than one liter of, let's say, syrup.

Following this line of thinking, with a different type of fuel (ethanol, nitromethane, kerosene?, maybe nitrous injection) and a solution to compress a large amount of air into that tiny engine, would it still be far from possible to reach 750hp?

I didn't plan to keep anything stock. Turning a car from 75hp from 750hp is impossible without modifying every functional part of it. My only requirement was that, if possible, I'd like to keep the same engine 'layout' or 'structure' or whatever it's called. Meaning that, I want the car to still have something reminding of it's origins.

Everyone can take a car and change out absolutely everything for massive amounts of power, but there's no 'legacy' in that. I want to be able to say 'yeah, we rebuilt the engine with better materials, we optimized the cooling channels and whatever else needs to be modified, but overall it's still the same engineering the french put into this engine'.

This will not be a road-legal car, will not be daily driven and will not participate in any competitions. This car is very close to my heart and I wanted something special to it. It's more of a.. media stunt if I can call it that.

I want it to be able to put out 750hp but won't be driven daily to that power. It will be more of a showroom car that, if I want to prove it's power to anyone, it will be capable of 750hp.

The fact that I work 14 hours a day with very few days off and one of my jobs revolves around the motorsport media scene means that I have the budget and the potential sponsors to support a project like this financially.

As a bottom note, I absolutely love the replies I've got from this forum. Everywhere else I went I was viewed as an insane guy who isn't worth people's time, criticized for the idea and all that comes with it. I know this isn't an ordinary idea for a build, I know it's very close to impossible to achieve without having some sort of F1 development team behind, but I also know there's a small chance it may work, which is good enough for me to try.

 

[obi_waynne]

I like your style, please keep us posted with your progress.

We champion the trailblazers and original thinkers. The first person to put a H20 into a Civic was ridiculed and now it's a commonplace upgrade. It takes someone like you to push the envelope for others and this is how we progress as a car building community.

Good to hear from you again.

 

[jbrickman0000]

OK, @goldie . You did mention interesting fuels in the original post, so clearly you're game for more or less anything-goes. We'll want to make sure you have a very good engine block and innards and all, because even 3x is three times OEM rating! So maybe that comes first, high-end alloy replacements for most of what's in your block, and checking of that block to make sure it's not going to just blow up or crack or ruin rings or something. Maybe really you do need a new small engine to start with, maybe not, but I'd get some input from the real engineering folks.

But back to the fuels. I really do wonder. If you went with nitro and pressure-aspiration and appropriate spark, you should be able to raise it a whole lot. I have to wonder if there are more arcane fuels which could do better. Anyone know?

And then there's the question of computer control of timing and mixture and all. You'll need a fully custom setup for that, made by one of the companies I've read about on these forums which does it. I imagine that using non-street fuels reduces the options a lot, at least for partially-turnkey kits.

And oddly I have something to offer you to give you a boost on top of everything else you do For a project like yours I'm eager to donate! https://motormercy.ponderworthy.com Do let me know!

 

[goldie]

And oddly I have something to offer you to give you a boost on top of everything else you do For a project like yours I'm eager to donate! https://motormercy.ponderworthy.com Do let me know!

This is purely amazing and I absolutely love it. I'm quite young, 20 years old, and I've lived more than half my life on the internet, so I was a member of hundreds of forums until now. No forum showed such level of support towards crazy stuff like this. Absolutely amazing. However, I don't like free money, I'd be thankful if you could donate some knowledge instead. However, when I'll get started with this project and I'll be sure that I have something solid coming up, you can donate, if you wish, in return of some advertisment in the form of a sponsor. Just like in business, you can't go to investors with just an idea. The idea is worth next to nothing, the execution is what matters.



Back to the subject. I always hated school but I love doing research for my projects, here's what I managed to learn through the breaks I take while working on my jobs.



Octane (C8H18, known as Gasoline*)
* - pure gasoline, the gasoline at gas stations have additives, including up to 10%-15% ethanol
Molecular weight: 114.23
Energy: 47.9Mj/kg

Ethanol (C2H6O, known as E85*)
* - E85 consists of 85% Ethanol + 15% gasoline
Molecular weight: 46.07
Energy: 26.4Mj/kg

Nitromethane (CH3NO2, known as Top Fuel)
Molecular weight: 61.04
Energy: 11.6Mj/kg


Gasoline is out of question, at this moment, without a F1 / Rally budget and development team, it would be extremely hard and expensive for me to develop 750hp with just gasoline. Now, the difference between methanol, nitromethane and gasoline, is that the first 2 also contain oxygen, this meaning that you can fit more fuel inside the cylinders without having to also include more air. Nitromethane contains 2 times the oxygen of methanol, hence why it is largely used in drag cars. Compared to a gasoline-powered engine, nitromethane has a 4 times smaller energy production, meaning that, with some ghetto math, one liter of gasoline would produce 4 times more power than one liter of nitromethane. The benefit is that, however, you can fit 8 times more nitromethane into an engine (gasoline has 26 molecules, while nitromethane only 6), and because nitromethane also comes with oxygen, with a modified engine to support nitromethane, at the same capacity (1.2l in our case), you can produce about 2.5 times more power. This, again, comes with the downside that, besides the price of nitromethane being way more than gasoline, you also burn 8 times more of it, ruining your fuel consumption. This isn't a worry of mine so we'll go over it. If we do some ghetto math again, in theory, by making an engine support nitromethane in place of gasoline, you can have 2.5 times more power, which means an engine that produces 300hp with gasoline, can produce 750hp with nitromethane. See where I go with this?

Of course this isn't gonna be simple since nitromethane also comes with downsides. First of all, it burns much slower than gasoline, which means that a single ignition cycle isn't enough to burn all of it, so you can't produce that 2.5 times more power anymore. For this, drag cars use 2 magnetos / MSD ignition (V8 engine, 2 heads, 2 magnetos). We're playing with a inline-4 here so we're gonna need only one. One goes for around $2k-$4k, the only problem is that they deliver 44amps at 50k volts, which is enough to deep fry a human. For this reason, drag car mechanics also need to swap the wires after each run because, of course, they melt.

MSD stands for multi spark discharge. I haven't spent that much time on this yet, but to my understanding, instead of having spark plugs connected to a computer and to the battery, the MSD connects right to your engine, like an alternator, charging a capacitator which sends a bigger, hotter and more powerful spark / multiple sparks per each ignition cycle, thus burning more fuel than traditional spark plugs.

The plus side of nitromethane is that it has a high latent heat of vaporization, meaning that, through vaporization, it absorbs a lot of heat, letting drag cars run without cooling systems.

In RC cars, nitromethane allows them to run a 1:1 displacement to horsepower ratio (1cc = 1hp), however, when you scale up, this ratio changes and a nitromethane-powered engine becomes quite destructive in order to achieve high powers (drag cars or 750hp out of 1.2l). For this reason, I'd be more inclined to go towards ethanol / nitrous injection or anything else that wouldn't require me to rebuild the engine every time i go for a run. I'll need to do more research into these fuel options, including methanol, kerosene and any other options there is, so if anyone is experienced in any alternative fuels and can share some knowledge, I'd be thankful.