270 horsepower from a 1.6 litre engine?

[Lowtimer]

Jonny_ said:

Wonder what the service intervals are? That's a very stressed little engine. Biggest reason for manufacturers keeping specific outputs down is longevity.

And weight, and cost.

You can make a 1.6 do pretty much any power you like if you are prepared to make it strong enough (therefore heavy enough and expensive enough) to rev very highly and/or run extremely high boost levels.

However this is not necessarily a satisfying thing to do, or to own. A reliable 200,000 mile life 450 hp 2.0 turbo four cylinder with all the turbos, intercoolers and other gubbins it needs, is perfectly achievable but the poverall package will have greater weight and bulk than a 450 bhp 6 litre plus Chevy LSx, will sound like a hairdryer, and will definitely cost a lot more.

There is really no inherent virtue in making small engines produce a lot of horsepower. It's only popular because when they are run at very low power settings (i.e. during emissions testing) they record better CO2 figures than big engines.

[robinessex]

IanCress said:

robinessex said:

IanCress said:

To be fair, 10 or 20 years ago a car like the RCZ-R wouldn't be possible. If you wanted 270bhp from an engine back then, you'd have to stick a 4 Litre V8 under the bonnet, which wouldn't be possible in a car the size of the Peugeot. Same goes for all the modern 250-300bhp hot hatches.

Not True. The Turbo F1 era produced 1,500 bhp from 1.5LTRS. Easy to detune down to 270bhp. Once an engine is supercharged by any means, it's size becomes irrelevant. It's just a fuel digesting device. The more you stuff in, the more bhp that comes out. You don't revs either.

My point still stands. How many of those 1.5 turbos were capable of 150k miles, with oil changes 20k miles apart? We didn't see them filtering down to road cars, because they weren't suitable.

All you need to do is reduce the boost. The highest loads in an engine are Inertia loads, a function of rpm. Keep the rpm levels to normal, sy 6,500 max, and the engind load peaks aren't any higher.

[ikarl]

IanCress said:

robinessex said:

IanCress said:

To be fair, 10 or 20 years ago a car like the RCZ-R wouldn't be possible. If you wanted 270bhp from an engine back then, you'd have to stick a 4 Litre V8 under the bonnet, which wouldn't be possible in a car the size of the Peugeot. Same goes for all the modern 250-300bhp hot hatches.

Not True. The Turbo F1 era produced 1,500 bhp from 1.5LTRS. Easy to detune down to 270bhp. Once an engine is supercharged by any means, it's size becomes irrelevant. It's just a fuel digesting device. The more you stuff in, the more bhp that comes out. You don't revs either.

My point still stands. How many of those 1.5 turbos were capable of 150k miles, with oil changes 20k miles apart? We didn't see them filtering down to road cars, because they weren't suitable.

In 1994 (20 years ago) you could buy a Subaru Impreza WRX STi which produced a reliable 300bhp from a 2ltr - you certainly didn't need a 4l V8

[Lowtimer]

robinessex said:

All you need to do is reduce the boost. The highest loads in an engine are Inertia loads, a function of rpm. Keep the rpm levels to normal, sy 6,500 max, and the engind load peaks aren't any higher.

That's just not right. If you run a standard shopping car 1.6 at 6500 rpm normally aspirated (around 0.95 bar absolute manifold pressure) and get 120 hp, and again at 6500 rpm it will need more like 3 bar absolute manifold pressure to get 270 hp (allowing for the pumping losses of the supercharging or turbocharging etc). A lot of the forces on the second engine are much higher, and the internals will have to be very substantially uprated from what would be optimum cost-effective engineering in the normally aspirated engine.

There is a lot more to engineering a highly turbocharged engine than dropping the static compression and slapping a massive blower on it, if you want it to work for a long time.

[IanCress]

ikarl said:

In 1994 (20 years ago) you could buy a Subaru Impreza WRX STi which produced a reliable 300bhp from a 2ltr - you certainly didn't need a 4l V8

This is the Impreza that has no power below 3000rpm, then goes utterly mental above it? Whilst Impreza buyers from the mid 90's may have been happy with this power delivery, it won't wash with modern buyers who want the torque of a large engine with the economy of a small one.

[robinessex]

Lowtimer said:

robinessex said:

All you need to do is reduce the boost. The highest loads in an engine are Inertia loads, a function of rpm. Keep the rpm levels to normal, sy 6,500 max, and the engind load peaks aren't any higher.

That's just not right. If you run a standard shopping car 1.6 at 6500 rpm normally aspirated (around 0.95 bar absolute manifold pressure) and get 120 hp, and again at 6500 rpm it will need more like 3 bar absolute manifold pressure to get 270 hp (allowing for the pumping losses of the supercharging or turbocharging etc). A lot of the forces on the second engine are much higher, and the internals will have to be very substantially uprated from what would be optimum cost-effective engineering in the normally aspirated engine.

There is a lot more to engineering a highly turbocharged engine than dropping the static compression and slapping a massive blower on it, if you want it to work for a long time.

Each rev of the engine produces a positive and negative inertia load in the engine. Both the piston and the conrod see a compresion and tension load, whilst the crank sees varying torsion loads. These loads far exceed combustion loads, and they increase as the square of the rpm. At the top of the tree, the old +20,000rpm F1 engines produced acceleration levels of 10,000g!!! That's 10,000 times the mass seen as a force. Back of an envelope calc give a piston 'mass' at full chat of circa 2,500kg !!!

[ikarl]

IanCress said:

ikarl said:

In 1994 (20 years ago) you could buy a Subaru Impreza WRX STi which produced a reliable 300bhp from a 2ltr - you certainly didn't need a 4l V8

This is the Impreza that has no power below 3000rpm, then goes utterly mental above it? Whilst Impreza buyers from the mid 90's may have been happy with this power delivery, it won't wash with modern buyers who want the torque of a large engine with the economy of a small one.

Stop moving the goal posts, to try and make a point.

You said the only way to get that kind of power was with a big capacity engine. That is simply not true. The technology has come on since then, granted, but reliable power was available 20 years ago.

The power delivery from the v2 STi wasn't as bad as you make out. Power would come in from around 2,700rpm and was easily drivable day-2-day - you make out as if it was undrivable below 3k then a full whack of boost, which simply isn't the case.

What is the power delivery like in this 1.6 270bhp engine? How does it feel when you drive it?

[LotusOmega375D]

Years ago Mitsubishi sold the 2 litre EVO 8 FQ400 with 405bhp, so 202.5bhp per litre.

[baccalad]

I've just found this video of a 0 - top speed run of the RCZ R, I don't know if it's partially down to short gearing but the thing looks like it needs wings to take off.

It'd be interesting to see a power and torque against rpm graph from a dyno readout.

http://youtu.be/v8U4i_GGH3Y

[Mr2Mike]

VeeFource said:

Motorbike engines don't need to produce as much torque low down though which means they can rev which reduces the loads on the crank etc.

As mentioned, it's a longevity thing. I don't think "ghastly" is the right word (I'd like to see you design better!), certainly not until we've seen how the RCZ's engine lasts anyway.

That's because bike engines aren't turbocharged. It's much more difficult to get high specific output from a normally aspirated engine than one with a turbocharger, so your argument doesn't really hold water. High revs don't reduce the load on the crank at all, they increase the stress on everything.

[liner33]

thatdude said:

I'd like to add that service intervals on many japanese 1000 cc sports bikes are somewhere around 5000 - 6000 miles. Suzuki tend to recommend 4000-ish miles, yamaha tend to go for 6000 miles. Honda, I'm not sure...the press reports lots of numbers, some as high as 8000 miles between oil changes.

Consider that cars often have service intervals of greater than 10,000 miles, and it's easy to argue that motorcycles do need to be serviced more regularly.

Edited by thatdude on Thursday 2nd October 08:31

Thats true but the intervals arent due to the engine being highly stressed and needing frequent oil changes but tha fact the oil is shared with the gearbox. Motorcycle gearboxes are very hard on synthetic engine oils

Those Scooby's and Evos mentioned before have to be serviced even more frequently than bikes.

Coming from the owner of one of those 180hp twincharged 1.4l engines I'm not convinced that these highly complex engines are the best way forward

[CarAbuser]

I've driven the Ford ecoboost engine in the form of a Fiesta and the 0.9L 3 cylinder Renault Clio.

Both engines are st in my opinion. The ecoboost engine has shocking fuel consumption and feels slow compared to the much more frugal Renault engine but both are st engines to drive.

I will personally buy the largest engine I can get my hands on until electric cars take over. Would much rather have a 8 cylinder engine producing 300bhp than a 3 cylinder one. In real world driving they are likely going to get similar fuel mileage.

The Golf R engine is a perfect example of this. 300bhp from a 2L engine but still only manages 26mpg in real world driving.
You have all the downsides of a small turbo engine and the running costs of a large engine. Plus the added reliability woes of a small engine with high power output.

Just seems lose-lose to me.

[zeppelin101]

CarAbuser said:

I've driven the Ford ecoboost engine in the form of a Fiesta and the 0.9L 3 cylinder Renault Clio.

Both engines are st in my opinion. The ecoboost engine has shocking fuel consumption and feels slow compared to the much more frugal Renault engine but both are st engines to drive.

I will personally buy the largest engine I can get my hands on until electric cars take over. Would much rather have a 8 cylinder engine producing 300bhp than a 3 cylinder one. In real world driving they are likely going to get similar fuel mileage.

The Golf R engine is a perfect example of this. 300bhp from a 2L engine but still only manages 26mpg in real world driving.
You have all the downsides of a small turbo engine and the running costs of a large engine. Plus the added reliability woes of a small engine with high power output.

Just seems lose-lose to me.

You have to drive a small engined car in a different manner to a larger engined one to extract the economy from it.

My mum averages 40mpg round town in her ecoboost Focus. My dad gets 50mpg out of it on a longer run.

Can't say I've ever found a V8 that manages anything like 40mpg day to day.

[Monty Python]

Maybe we should go back to 2l V8s as fitted to the Dino - they produced around 270bhp.

[CarAbuser]

zeppelin101 said:

You have to drive a small engined car in a different manner to a larger engined one to extract the economy from it.

My mum averages 40mpg round town in her ecoboost Focus. My dad gets 50mpg out of it on a longer run.

Can't say I've ever found a V8 that manages anything like 40mpg day to day.

I did the same trip two weeks back-to-back.

First week in an ecoboost fiesta and second in my own car.
Both cars used exactly the same fuel for the week. I couldn't find the trip computer on the Fiesta but my car was showing 30mpg.

It's not as if I was beating on the car. It just seemed to drink fuel on a 80mph motorway cruise.

There's quite a few Golf R owners complaining about the fact they are only getting a fraction of the promised fuel economy.

[liner33]

zeppelin101 said:

You have to drive a small engined car in a different manner to a larger engined one to extract the economy from it.

My mum averages 40mpg round town in her ecoboost Focus. My dad gets 50mpg out of it on a longer run.

Can't say I've ever found a V8 that manages anything like 40mpg day to day.

Thats on a 100hp car though right ? I can think of a lot of significantly more powerful engines that will match those figures

[Sinatra21]

Plenty of turbocharged mk1 mx5s that run 240-260 bhp without problems. Some are nearly 25 years old now too.

[liner33]

Sinatra21 said:

Plenty of turbocharged mk1 mx5s that run 240-260 bhp without problems. Some are nearly 25 years old now too.

How many of them cover at least 10,000 miles per year?

[Matthen]

baccalad said:

I've just found this video of a 0 - top speed run of the RCZ R, I don't know if it's partially down to short gearing but the thing looks like it needs wings to take off.

It'd be interesting to see a power and torque against rpm graph from a dyno readout.

http://youtu.be/v8U4i_GGH3Y

Impressive. But by the noise when he changed gear, the gear shift quality is utterly dire.

[zeppelin101]

liner33 said:

Thats on a 100hp car though right ? I can think of a lot of significantly more powerful engines that will match those figures

A 125hp car. The point of comparison was "why can't I just have a V8 that gets the same MPG" but no V8 will get anywhere near 50mpg. More to the point, they had a diesel before which was always going to cause trouble given that my mum predominantly drives round town so if you were going to throw a diesel into the mix for short journeys - it doesn't wash.

I know it's fun to beat up on these new engines because they haven't got 6+ cylinders and make many hundreds of horsepower and sound rubbish but the fact is they really aren't as bad as PH would have you believe.

I'm clearly wasting my breath though.