MR2 Roadster Owners Club

The Workshop => General => Topic started by: kwnelson on February 20, 2020, 16:26

Title: cheapest way to boost power
Post by: kwnelson on February 20, 2020, 16:26
Without a large outlay, what is the most economical way of increasing BHP.    Did a chip on my 2ltr Qashqai Diesel,transformation 15% increase,   any thoughts?
Title: Re: cheapest way to boost power
Post by: househead on February 20, 2020, 16:33
Depends what you consider to be a large outlay? :)

Unfortunately there aren't many gains to be had without going turbo/supercharger or throwing another engine in. There are some NA 1zz cars that have dyno'd to 170 BHP, but afaik they've got aftermarket cams and (probably) aftermarket ECUs.

MAF Mod might be worth a look, doesn't cost much (2zz injectors + a MAF spacer). Not sure what the gains relate to in power terms though.

It's rather unfortunate that the stock ECU cannot be simply remapped.
Title: Re: cheapest way to boost power
Post by: Gatouzze on February 20, 2020, 16:56
Quote from: househead on February 20, 2020, 16:33Depends what you consider to be a large outlay? :)

Unfortunately there aren't many gains to be had without going turbo/supercharger or throwing another engine in. There are some NA 1zz cars that have dyno'd to 170 BHP, but afaik they've got aftermarket cams and (probably) aftermarket ECUs.

MAF Mod might be worth a look, doesn't cost much (2zz injectors + a MAF spacer). Not sure what the gains relate to in power terms though.

It's rather unfortunate that the stock ECU cannot be simply remapped.

Like he said, the ECU cannot be tuned directly... you need either a stand alone ECU or a piggyback but do not expect 15%.

If you would like to go the piggyback way, I am selling mine atm ;)
Title: Re: cheapest way to boost power
Post by: Carolyn on February 20, 2020, 17:23
Buy a Porker.
Title: Re: cheapest way to boost power
Post by: Call the midlife! on February 20, 2020, 17:30
Quote from: Carolyn on February 20, 2020, 17:23Buy a Porker.
I AM a porker, doesn't do my performance any favours either 😆
Title: Re: cheapest way to boost power
Post by: househead on February 20, 2020, 17:36
You could always paint a stripe on your car? That's worth at least 15bhp :D
Title: Re: cheapest way to boost power
Post by: Gaz mr-s on February 20, 2020, 17:48
I think the O/P is probably going to be a little disappointed with the answers.   ;D
Title: Re: cheapest way to boost power
Post by: Petrus on February 20, 2020, 18:02
1. There is no cheap way to a large boost of power without áctually boosting the intake. Even spending on a change of cams and head porting gives very modest gains only.

2. Evidence based best practice:

- Have a look at the unltimate inlet thread. You will find that the intake is very good already.
- MAF mod. ; tricking the ecu.
- Free up the exhaust. The OEM exhaust is thé big restriction.
Title: Re: cheapest way to boost power
Post by: Call the midlife! on February 20, 2020, 18:17
Quote from: Gaz mr-s on February 20, 2020, 17:48I think the O/P is probably going to be a little disappointed with the answers.  ;D
A bit like the power...
Title: Re: cheapest way to boost power
Post by: s12vea on February 20, 2020, 18:19
The cheapest way to get more power out of a 2 is to buy one which has already been turbo charged or engine swapped.

Title: Re: cheapest way to boost power
Post by: Gaz2405 on February 20, 2020, 19:22
If you're handy on the spanners and look out for items second hand, you can self build turbo for around £2-£2.5k. Which also includes mapping it yourself....

Title: Re: cheapest way to boost power
Post by: jvanzyl on February 20, 2020, 21:09
I'm surprised no one has mentioned lightening the car yet...
Title: Re: cheapest way to boost power
Post by: Ardent on February 20, 2020, 21:15
Quote from: jvanzyl on February 20, 2020, 21:09I'm surprised no one has mentioned lightening the car yet...
I was going to, but original question was about "increasing BHP"
Title: Re: cheapest way to boost power
Post by: jvanzyl on February 20, 2020, 21:41
Quote from: Ardent on February 20, 2020, 21:15
Quote from: jvanzyl on February 20, 2020, 21:09I'm surprised no one has mentioned lightening the car yet...
I was going to, but original question was about "increasing BHP"

I understand but the point of Bhp is to go faster, you can go faster by being lighter... plus if money is a key concern- taking stuff out is a viable solution
Title: Re: cheapest way to boost power
Post by: Ardent on February 20, 2020, 21:53
I don't disagree.

But the op, was also using their point of reference of a simple re-map. Wants more BHP, made no ref to wanting to lose creature comforts. Not sure money is an issue, has some, just looking for most economical option.

Had the question been phrased differently, we would be up to 3 pages of suggestions.
Title: Re: cheapest way to boost power
Post by: Joesson on February 20, 2020, 21:56
Quote from: jvanzyl on February 20, 2020, 21:41
Quote from: Ardent on February 20, 2020, 21:15
Quote from: jvanzyl on February 20, 2020, 21:09I'm surprised no one has mentioned lightening the car yet...
I was going to, but original question was about "increasing BHP"

I understand but the point of Bhp is to go faster, you can go faster by being lighter... plus if money is a key concern- taking stuff out is a viable solution
[/quot
Quote from: jvanzyl on February 20, 2020, 21:09I'm surprised no one has mentioned lightening the car yet...

@Petrus has been away in the big city.
Title: Re: cheapest way to boost power
Post by: shnazzle on February 20, 2020, 22:08
Doesn't say how much power :) 

Catless manifold
Decat pipe
2nd hand PFC standalone with suiting map
Stage1 cams

Estimated increase = 20% for about 1500ish.

Much easier to make gains via "chiptune" on a turbo car and a diesel. Petrol N/A is a more mechanical ballgame.
On one of our old turbo diesel cars, 400 quid gave us a 25% boost in power. Just doesn't exist for N/A, even if you could fettle the ecu.
Title: Re: cheapest way to boost power
Post by: Ardent on February 20, 2020, 22:20
Wow!
Just had a penny dropping moment, realizing how much of a peasant I am.

That 1500ish is viewed as economical.

I need to re-calibrate.
Title: Re: cheapest way to boost power
Post by: Call the midlife! on February 20, 2020, 22:22
Quote from: Ardent on February 20, 2020, 22:20Wow!
Just had a penny dropping moment, realizing how much of a peasant I am.

That 1500ish is viewed as economical.

I need to re-calibrate.
It's quite a conservative "ish" as well, probably another 2-300 ish...
Title: Re: cheapest way to boost power
Post by: Bernie on February 20, 2020, 22:33
Quote from: Call the midlife! on February 20, 2020, 22:22
Quote from: Ardent on February 20, 2020, 22:20Wow!
Just had a penny dropping moment, realizing how much of a peasant I am.

That 1500ish is viewed as economical.

I need to re-calibrate.
It's quite a conservative "ish" as well, probably another 2-300 ish...

"Ish" nowhere near

138 to 171BHP = 24% increase

From Robs files

Crower Stage 1 Cams (Monkey Wrench USA). £100
Apexi Power FC (ECU) with Commander hand controller £1,000
Mapping / Dyno by Noble Motorsport 171 BHP.   £550
Fidanza lightweight flywheel £350
Up graded serpentine belt tensioner £75
PPE Cold Air Induction system (Monkey Wrench USA) £300
Zero - 4 into 2 Equal Length, tuned collector, Manifold SS.  £575
Silverstone Performance De-cat pipe, fitted with 200 CEL Sports Cat £500
Blueflame Custom Twin Exhaust.  £325

Parts Total £3,775


Title: Re: cheapest way to boost power
Post by: Joesson on February 20, 2020, 22:37
Quote from: Call the midlife! on February 20, 2020, 22:22
Quote from: Ardent on February 20, 2020, 22:20Wow!
Just had a penny dropping moment, realizing how much of a peasant I am.

That 1500ish is viewed as economical.

I need to re-calibrate.
It's quite a conservative "ish" as well, probably another 2-300 ish...



Those figures are a large % of the value of our cars !

 PS @Bernie's figures represent replacement vehicle costs for our cars!,
Title: Re: cheapest way to boost power
Post by: Zxrob on February 20, 2020, 22:46
Quote from: Carolyn on February 20, 2020, 17:23Buy a Porker.

This ^^^^

Rob
Title: Re: cheapest way to boost power
Post by: shnazzle on February 20, 2020, 22:57
Quote from: Bernie on February 20, 2020, 22:33
Quote from: Call the midlife! on February 20, 2020, 22:22
Quote from: Ardent on February 20, 2020, 22:20Wow!
Just had a penny dropping moment, realizing how much of a peasant I am.

That 1500ish is viewed as economical.

I need to re-calibrate.
It's quite a conservative "ish" as well, probably another 2-300 ish...

"Ish" nowhere near

138 to 171BHP = 24% increase

From Robs files

Crower Stage 1 Cams (Monkey Wrench USA). £100
Apexi Power FC (ECU) with Commander hand controller £1,000
Mapping / Dyno by Noble Motorsport 171 BHP.  £550
Fidanza lightweight flywheel £350
Up graded serpentine belt tensioner £75
PPE Cold Air Induction system (Monkey Wrench USA) £300
Zero - 4 into 2 Equal Length, tuned collector, Manifold SS.  £575
Silverstone Performance De-cat pipe, fitted with 200 CEL Sports Cat £500
Blueflame Custom Twin Exhaust.  £325

Parts Total £3,775



That's for all brand new kit Bernie :) I'm going off 2nd hand for the PFC,stock backbox, no intake, no light flywheel, and a map that just needs tweaking. 


My point was really; 1500 is what's going to get you near 15% gains.
Cheapest way to add power is 2nd hand manifold without pre-cats and a 2nd hand decat or sports cat. Won't be much. But for maybe less than 200 you'd feel a noticeable difference on the bum dyno.
Title: Re: cheapest way to boost power
Post by: Bernie on February 20, 2020, 23:04
Quote from: Joesson on February 20, 2020, 22:37
Quote from: Call the midlife! on February 20, 2020, 22:22
Quote from: Ardent on February 20, 2020, 22:20Wow!
Just had a penny dropping moment, realizing how much of a peasant I am.

That 1500ish is viewed as economical.

I need to re-calibrate.
It's quite a conservative "ish" as well, probably another 2-300 ish...



Those figures are a large % of the value of our cars !

 PS @Bernie's figures represent replacement vehicle costs for our cars!,


The time Rob was purchasing was around 2012 so value of car v Parts was significantly different

But making the point that there's no easy way on our 1ZZ to improve BHP and Toyota squeezed quite a bit out of it in stock form

Tweaking a diesel is a completely different matter a simple tuning box @ £359 increased my TT from 170 to 205 BHP
Title: Re: cheapest way to boost power
Post by: Petrus on February 20, 2020, 23:24
Quote from: Ardent on February 20, 2020, 21:53I don't disagree.

But the op, was also using their point of reference of a simple re-map. Wants more BHP, made no ref to wanting to lose creature comforts. Not sure money is an issue, has some, just looking for most economical option.

Had the question been phrased differently, we would be up to 3 pages of suggestions.

Simples.
Indeed; the op asked for cheap power boost.
Hence me not going off topic ;-)

Title: Re: cheapest way to boost power
Post by: Petrus on February 20, 2020, 23:26
Quote from: Bernie on February 20, 2020, 23:04Tweaking a diesel is a completely different matter a simple tuning box @ £359 increased my TT from 170 to 205 BHP

TURBO diesel! Quite a difference.
Title: Re: cheapest way to boost power
Post by: Petrus on February 20, 2020, 23:34
@op

Have a browse through Belle´s thread on reader´s rides.

I deleted a lót of stuff. Have some 10-15% more oompf pushing 15% less weight. The oomph was cheap, most weight was for free. The process as much fun as the result  ;D
Title: Re: cheapest way to boost power
Post by: Ardent on February 20, 2020, 23:56
So 26 posts later.

Calling KWnelson, come in Kwnelson.
Title: Re: cheapest way to boost power
Post by: househead on February 20, 2020, 23:58
Quote from: Ardent on February 20, 2020, 23:56So 26 posts later.

Calling KWnelson, come in Kwnelson.

What odds will you give me that they're outside painting that stripe? :D
Title: Re: cheapest way to boost power
Post by: Chriss on February 21, 2020, 00:44
A cheap 800 pound 2zz engine, a new manifold and exhaust and a few mates with space to work and you swap the engine yourselves, keep the 5 speed. This is the cheapest way to get a BHP boost. It is not the right way but it is the cheapest.
Title: Re: cheapest way to boost power
Post by: s12vea on February 21, 2020, 08:16
Unless you are going forced induction I would just focus on refresh suspension, geo and good branded tyres all round with correct stagger and pressure.
The above would have more of impact. 
Title: Re: cheapest way to boost power
Post by: Call the midlife! on February 21, 2020, 08:50
Quote from: Chriss on February 21, 2020, 00:44A cheap 800 pound 2zz engine, a new manifold and exhaust and a few mates with space to work and you swap the engine yourselves, keep the 5 speed. This is the cheapest way to get a BHP boost. It is not the right way but it is the cheapest.
If you can meet all those criteria you're probably right with this, if lift is your thing, this route does tick a lot of boxes.
Title: Re: cheapest way to boost power
Post by: Joesson on February 21, 2020, 09:09
I do recall a certain TV motoring programme presenter, one of a trio, at one time suggesting that the fun starts at around 100 bhp(/ tonne)!
Title: Re: cheapest way to boost power
Post by: Petrus on February 21, 2020, 10:18
Quote from: Joesson on February 21, 2020, 09:09I do recall a certain TV motoring programme presenter, one of a trio, at one time suggesting that the fun starts at around 100 bhp(/ tonne)!


How much was he referring to? Long tonne, short tonne, kilos, pounds, stones?


(https://external-content.duckduckgo.com/iu/?u=http%3A%2F%2F4.bp.blogspot.com%2F-GIrL3mBjWmg%2FUA4TqXLJqDI%2FAAAAAAAAB4o%2FOjWkPiIYBQA%2Fs1600%2Fjuly%2B23%2Bpost%2Bton-of-bricks.jpg&f=1&nofb=1)
Title: Re: cheapest way to boost power
Post by: Joesson on February 21, 2020, 12:22
@Petrus , my understanding is that a ton refers to 2240 lbs in the UK somewhat less in the USA and that is where the long and short ton reference came from. The tonne in my understanding is 1000kg around 2200 lb in real money.  Please don't start on about weight and force!
In the UK we have been trying to adopt a System Internationale ( SI system , that most call a metric system) since the early 1970's with varying success, I believe it's a generational thing. I am of a generation that was educated in measurement's that included rods, poles, pecks, stones, chains, furlongs not to mention feet inches miles and metres, litres , kilograms and parts or multiples thereof!
Title: Re: cheapest way to boost power
Post by: Call the midlife! on February 21, 2020, 12:45
Quote from: Joesson on February 21, 2020, 12:22@Petrus , my understanding is that a ton refers to 2240 lbs in the UK somewhat less in the USA and that is where the long and short ton reference came from. The tonne in my understanding is 1000kg around 2200 lb in real money.  Please don't start on about weight and force!
In the UK we have been trying to adopt a System Internationale ( SI system , that most call a metric system) since the early 1970's with varying success, I believe it's a generational thing. I am of a generation that was educated in measurement's that included rods, poles, pecks, stones, chains, furlongs not to mention feet inches miles and metres, litres , kilograms and parts or multiples thereof!
Aaah, chains, that takes me back to my youth, measuring the perimeter of the fields with chains. Can't remember how long they were but you knew you'd been using them all day.
Title: Re: cheapest way to boost power
Post by: Petrus on February 21, 2020, 12:51
Quote from: Joesson on February 21, 2020, 12:22@Petrus , my understanding is that a ton refers to 2240 lbs in the UK somewhat less in the USA and that is where the long and short ton reference came from. The tonne in my understanding is 1000kg around 2200 lb in real money.  Please don't start on about weight and force!
In the UK we have been trying to adopt a System Internationale ( SI system , that most call a metric system) since the early 1970's with varying success, I believe it's a generational thing. I am of a generation that was educated in measurement's that included rods, poles, pecks, stones, chains, furlongs not to mention feet inches miles and metres, litres , kilograms and parts or multiples thereof!

So in SI language 100 hp per 1000 kg.

The bog standard MR2 comfortably exceeds that ;-)

Mine is about 175 / tonne.

Thanks for bringing it up btw.; it is good to look at it this way as it is as close as it comes to an objectove comparative criterium for apples and pears.
Title: Re: cheapest way to boost power
Post by: Joesson on February 21, 2020, 13:11
Quote from: Call the midlife! on February 21, 2020, 12:45
Quote from: Joesson on February 21, 2020, 12:22@Petrus , my understanding is that a ton refers to 2240 lbs in the UK somewhat less in the USA and that is where the long and short ton reference came from. The tonne in my understanding is 1000kg around 2200 lb in real money.  Please don't start on about weight and force!
In the UK we have been trying to adopt a System Internationale ( SI system , that most call a metric system) since the early 1970's with varying success, I believe it's a generational thing. I am of a generation that was educated in measurement's that included rods, poles, pecks, stones, chains, furlongs not to mention feet inches miles and metres, litres , kilograms and parts or multiples thereof!
Aaah, chains, that takes me back to my youth, measuring the perimeter of the fields with chains. Can't remember how long they were but you knew you'd been using them all day.

22 yards was my recollection, stumps to stumps on a cricket pitch, or as confirmed by Wikipedia- The chain is a unit of length equal to 66 feet. It is subdivided into 100 links or 4 rods.
Title: Re: cheapest way to boost power
Post by: Joesson on February 21, 2020, 13:19
Quote from: Petrus on February 21, 2020, 12:51
Quote from: Joesson on February 21, 2020, 12:22@Petrus , my understanding is that a ton refers to 2240 lbs in the UK somewhat less in the USA and that is where the long and short ton reference came from. The tonne in my understanding is 1000kg around 2200 lb in real money.  Please don't start on about weight and force!
In the UK we have been trying to adopt a System Internationale ( SI system , that most call a metric system) since the early 1970's with varying success, I believe it's a generational thing. I am of a generation that was educated in measurement's that included rods, poles, pecks, stones, chains, furlongs not to mention feet inches miles and metres, litres , kilograms and parts or multiples thereof!

So in SI language 100 hp per 1000 kg.

The bog standard MR2 comfortably exceeds that ;-)

Mine is about 175 / tonne.

Thanks for bringing it up btw.; it is good to look at it this way as it is as close as it comes to an objectove comparative criterium for apples and pears.

Power / weight ratio has to be the way to compare performance one vehicle with another. As you have mentioned, often, adding lightness is a way of improving the ratio and thereby improving performance.
Title: Re: cheapest way to boost power
Post by: Petrus on February 21, 2020, 13:20
Quote from: Joesson on February 21, 2020, 13:11The chain is a unit of length equal to 66 feet.

Feet still don´t compute on this side of the Channel ;-)
Title: Re: cheapest way to boost power
Post by: Joesson on February 21, 2020, 13:26
Quote from: Petrus on February 21, 2020, 13:20
Quote from: Joesson on February 21, 2020, 13:11The chain is a unit of length equal to 66 feet.

Feet still don´t compute on this side of the Channel ;-)

Neither does cricket I guess😉
Title: Re: cheapest way to boost power
Post by: Petrus on February 21, 2020, 13:29
Quote from: Joesson on February 21, 2020, 13:19
Quote from: Petrus on February 21, 2020, 12:51Thanks for bringing it up btw.; it is good to look at it this way as it is as close as it comes to an objectove comparative criterium for apples and pears.

Power / weight ratio has to be the way to compare performance one vehicle with another. As you have mentioned, often, adding lightness is a way of improving the ratio and thereby improving performance.

Well, yes for performance limited to accelleration/speed.
It must be noted that the shortcoming is that power only counts in accelleration whereas weight, mass counts whichever way the G-forces work on it.

To refer to a US slogan; there ís a substitute for cubic inches; adding lightness is even better ;-)

Anyway; short of spending on forced induction there is not much to be done to squeeze power from the 1ZZ.
Title: Re: cheapest way to boost power
Post by: househead on February 21, 2020, 13:31
Ah, the SI number system. Great until it relates to computers, by which point one also must understand that the prefixes used in the SI number system relate to different numbers when applied to binary.

1 kilobyte is 1024 bytes, not 1000. SI system actually calls this a "kibibyte" (which practically nobody uses). This confusion has led to lawsuits over stated capacities for memory and hard drives and the like.

Apologies for going waaaaaaaay OT
Title: Re: cheapest way to boost power
Post by: Joesson on February 21, 2020, 13:44
For the very pedantic ( such as @househead) among the readers bhp/ tonne is in itself not a correct measure. The reference I first made was my recollection of what was said on a TV programme. It could equally have been bhp/ ton, but the difference of 40 lb is not much more than a good lunch and the gf's handbag. Those that are bothered the following is courtesy of Which:

Most cars measure power by the horse, but bhp isn't the only unit manufacturers use to tell us how much oomph there is in the engine. Pferdestärke, or PS for short, and Kilowatts (kW) are both lesser used units for determining a car's engine power that mostly show up in mainland Europe.

So for the benefit of our international membership I guess I should have written PS/ tonne!
Title: Re: cheapest way to boost power
Post by: Joesson on February 21, 2020, 13:46
For those that remember playing outside and " having to go in", I have to go in now😉
Title: Re: cheapest way to boost power
Post by: Petrus on February 21, 2020, 13:58
Quote from: Joesson on February 21, 2020, 13:44For the very pedantic ( such as @househead) among the readers bhp/ tonne is in itself not a correct measure. The reference I first made was my recollection of what was said on a TV programme. It could equally have been bhp/ ton, but the difference of 40 lb is not much more than a good lunch and the gf's handbag. Those that are bothered the following is courtesy of Which:

Most cars measure power by the horse, but bhp isn't the only unit manufacturers use to tell us how much oomph there is in the engine. Pferdestärke, or PS for short, and Kilowatts (kW) are both lesser used units for determining a car's engine power that mostly show up in mainland Europe.

So for the benefit of our international membership I guess I should have written PS/ tonne!


Never mind the tv person.
Let´s go for 100 kW / 1000 kg.
Our MR sits about right on it.
Title: Re: cheapest way to boost power
Post by: SV-3 on February 21, 2020, 14:00
Quote from: Joesson on February 21, 2020, 13:44For the very pedantic ( such as @househead) among the readers bhp/ tonne is in itself not a correct measure. The reference I first made was my recollection of what was said on a TV programme. It could equally have been bhp/ ton, but the difference of 40 lb is not much more than a good lunch and the gf's handbag. Those that are bothered the following is courtesy of Which:

Most cars measure power by the horse, but bhp isn't the only unit manufacturers use to tell us how much oomph there is in the engine. Pferdestärke, or PS for short, and Kilowatts (kW) are both lesser used units for determining a car's engine power that mostly show up in mainland Europe.

So for the benefit of our international membership I guess I should have written PS/ tonne!

If "my memory serves me well" (guess the song) ;)  I think it was an item on Top Gear looking at what was a "sensible limit" on the power that could be used on a front wheel drive car before it became undriveable as "torque steer" took over.
Title: Re: cheapest way to boost power
Post by: SV-3 on February 21, 2020, 14:12
Quote from: Petrus on February 21, 2020, 13:20
Quote from: Joesson on February 21, 2020, 13:11The chain is a unit of length equal to 66 feet.

Feet still don´t compute on this side of the Channel ;-)
May I help?
1 foot = 12 inches
1 inch = 25.40mm(exactly)
Therefore 1 foot = 12 x 25.40 = 304.80mm(exactly) 8)
Title: Re: cheapest way to boost power
Post by: househead on February 21, 2020, 14:45
Quote from: Petrus on February 21, 2020, 13:58Never mind the tv person.
Let´s go for 100 kW / 1000 kg.
Our MR sits about right on it.

or 100 milliwatt per kilo :)
Title: Re: cheapest way to boost power
Post by: Petrus on February 21, 2020, 15:23
Quote from: SV-3 on February 21, 2020, 14:12Therefore 1 foot = 12 x 25.40 = 304.80mm(exactly) 8)

Mine are not ...
Title: Re: cheapest way to boost power
Post by: Zxrob on February 21, 2020, 15:32
Quote from: Joesson on February 21, 2020, 13:19Power / weight ratio has to be the way to compare performance one vehicle with another. As you have mentioned, often, adding lightness is a way of improving the ratio and thereby improving performance.

Off topic, but sort of on topic, one of my bike has a power to weight ratio of 1063bhp/tonne and that's at the rear wheel

I would suggest that a standard MR2 will be making around 110-120 at the wheels, true power not crank figures

Rob
Title: Re: cheapest way to boost power
Post by: Joesson on February 21, 2020, 17:44
Quote from: SV-3 on February 21, 2020, 14:00
Quote from: Joesson on February 21, 2020, 13:44For the very pedantic ( such as @househead) among the readers bhp/ tonne is in itself not a correct measure. The reference I first made was my recollection of what was said on a TV programme. It could equally have been bhp/ ton, but the difference of 40 lb is not much more than a good lunch and the gf's handbag. Those that are bothered the following is courtesy of Which:

Most cars measure power by the horse, but bhp isn't the only unit manufacturers use to tell us how much oomph there is in the engine. Pferdestärke, or PS for short, and Kilowatts (kW) are both lesser used units for determining a car's engine power that mostly show up in mainland Europe.

So for the benefit of our international membership I guess I should have written PS/ tonne!

If "my memory serves me well" (guess the song) ;)  I think it was an item on Top Gear looking at what was a "sensible limit" on the power that could be used on a front wheel drive car before it became undriveable as "torque steer" took over.

"Sensible" is not a word I would use for the TG presenter I'm  thinking of. I thought it was cars in general but I wouldn't bet my pension on it.
Title: Re: cheapest way to boost power
Post by: Joesson on February 21, 2020, 17:53
Quote from: Zxrob on February 21, 2020, 15:32
Quote from: Joesson on February 21, 2020, 13:19Power / weight ratio has to be the way to compare performance one vehicle with another. As you have mentioned, often, adding lightness is a way of improving the ratio and thereby improving performance.

Off topic, but sort of on topic, one of my bike has a power to weight ratio of 1063bhp/tonne and that's at the rear wheel

I would suggest that a standard MR2 will be making around 110-120 at the wheels, true power not crank figures

Rob

I would be wearing brown trousers if on your bike! I am not a motorcyclist having ridden only one motorised two wheeler, on one wheel, for around 200 yards in my teens. But " affordable" bikes I guess must take first place for power/ weight ratio. Maybe something very exotic petrol powered or now an electric or hybrid would challenge that on four wheels.
Title: Re: cheapest way to boost power
Post by: Petrus on February 21, 2020, 17:54
Quote from: SV-3 on February 21, 2020, 14:00If "my memory serves me well" (guess the song) ;)  I think it was an item on Top Gear looking at what was a "sensible limit" on the power that could be used on a front wheel drive car before it became undriveable as "torque steer" took over.

I have heard the 100 hp per 1000 kilo back in the late seventies as the definition of a performance car.

Concerning fwd I´ve heard and read umpteen limits that shifted over the decades as front suspension geometry design developed. Where are we currently? 320 hp in a Civic?
Title: Re: cheapest way to boost power
Post by: Petrus on February 21, 2020, 20:58
Let us stay with the numbers for a bit and play with the 135 hp per 1000 kg.

Reducing 100 kilo equals adding 13.5 hp.

The bonus of that is that adding kWs to the lower weight multiplies the ratio per 1000 kilo by 1.11 so adding 13.5 gets to be 14.85.

Playing a bit more;
with a 190 hp TTE turbo and 1050 kilo we get 18 hp per 1000 kg.
with only 160 n.a. but 900 kilo we get 17.8 hp and a 14% lighter car.

Title: Re: cheapest way to boost power
Post by: shnazzle on February 21, 2020, 21:19
Jesus. This thread escalated. 
Not sure we're still on topic.
Title: Re: cheapest way to boost power
Post by: Petrus on February 21, 2020, 22:34
Quote from: shnazzle on February 21, 2020, 21:19Jesus. This thread escalated.
Not sure we're still on topic.

Let the OP judge ;-)

In mý perception we are extensively exhausting ´more performance for limited outlay´ :-)
Title: Re: cheapest way to boost power
Post by: Zxrob on February 21, 2020, 22:38
Quote from: Petrus on February 21, 2020, 20:58Reducing 100 kilo equals adding 13.5 hp.

No it does not, it increases the power to weight ratio, not magically add "real power"

Rob
Title: Re: cheapest way to boost power
Post by: Petrus on February 21, 2020, 22:40
Quote from: Zxrob on February 21, 2020, 22:38
Quote from: Petrus on February 21, 2020, 20:58Reducing 100 kilo equals adding 13.5 hp.

No it does not, it increases the power to weight ratio, not magically add "real power"

Rob

Hence ´equals´ and not ´adds´.
And in effect it does MÓRE for performance than adding 13.5 would ;-)
Title: Re: cheapest way to boost power
Post by: Zxrob on February 21, 2020, 22:45
Quote from: Petrus on February 21, 2020, 22:40
Quote from: Zxrob on February 21, 2020, 22:38
Quote from: Petrus on February 21, 2020, 20:58Reducing 100 kilo equals adding 13.5 hp.

No it does not, it increases the power to weight ratio, not magically add "real power"

Rob

Hence ´equals´ and not ´adds´.
And in effect it does MÓRE for performance than adding 13.5 would ;-)

You incorporated the word "adding" in your post

Have you been a politician at some time ;)

Rob
Title: Re: cheapest way to boost power
Post by: kwnelson on February 21, 2020, 22:54
Ardent,  Sorted,  I am going to shed 2 stones from my body weight of 16 stone.  I will let the people of the Forum calculate the net gain on the road.    2/16 x launch =  ?
Title: Re: cheapest way to boost power
Post by: Zxrob on February 21, 2020, 23:21
Quote from: Joesson on February 21, 2020, 17:53I would be wearing brown trousers if on your bike! I am not a motorcyclist having ridden only one motorised two wheeler, on one wheel, for around 200 yards in my teens. But " affordable" bikes I guess must take first place for power/ weight ratio. Maybe something very exotic petrol powered or now an electric or hybrid would challenge that on four wheels.

Power is useless without control ;)

Take a look at this vid (skip to 7.0 min), highlights the difference between performance road bike and car, the bike is the same as mine, but 100k less than the porker

Rob

https://www.youtube.com/watch?v=Inl6o1psp5Q
Title: Re: cheapest way to boost power
Post by: Petrus on February 22, 2020, 09:01
Quote from: Zxrob on February 21, 2020, 22:45You incorporated the word "adding" in your post

Have you been a politician at some time ;)

Rob

No need to stab under water. Regardless of the wink.

You may very well have a point but nevertheless a bit of flexibility from your part, especially since you appearantly master your language better, would suit you; I am after all expressing myself in my third language. No excuse, just be kind ;-)

Have a nice day. Have fun. Enjoy the power/weight ratio whichever that may be!
Title: Re: cheapest way to boost power
Post by: shnazzle on February 22, 2020, 10:50
Topic locked. Gone further astray than the characters of the Incredible Journey, except for that those characters made it back home...
End