What would you really prefer ?
A new modern engine or an old school or as some may call it "outdated" engine ?
Being a petrol head sometimes means not being so modern also..
I'd love engines which are not so "cutting edge".. by now probably u must be assuming this guy is too old to even blog here..
Some of the modern engines take the fun out of owning and mantaining a car.
E.g the igition systems of the older vehicles which came with a mechanical/vacum advance .. it is probably more fun for the petrohead to tune it and get it with right dwell angle, maybe tweak the distributor with diff aftermarket parts to alter the advance curve etc
It was probably more work, less accurate, lower performance but probably more DIY thingies for the "car nut"
More modern engines came with the distributor and the ECU based advance curve control..
Not much to tweak unless we have a laptop or a aftermarket programmable ignition system.. fine - still fun but not so analog or "get your hands dirty" type of fun.
This stil leaves some room for some teweaks to the base/static ignition via distributor.. this is still ok.
Fast forward to newer engines with a coil on plug - no distributor, direct ECU trigger for the right spark timing, no mechanical tolerances in the picture - efficient , reliable but fully digital.
Works well but there is no longer the "hands on" feel to this..
Moving on to tappets/valve clearances ..Love the tweaks/mods which and the regular tappets
Self compensating hydraulic tappets ... will definately miss the feeler gauge and the guesswork how much clearance will work best ..of course within the range specified by the manufacturer
Fueling : tweaking the A/F ratio via the carb instead of the fuelling maps via the ECU.. this is very efficient and I love this more than the carb.
Here its ok to be a bit modern, but for the more hardcore older gen tuners probably this is more fun - and I have respect for these guys - its much tougher getting it right with the carbs.
I like the ease in and accuracy with which we can tune the curves ..probably Im leaning towards modern engines here.
Coming to garboxes - what the hell is going on ??? is this a joke ?
Hardcore , purpose built cars not having manual gearboxes.. look at the silly 6 speed twin clutch Evox, what u guys upto? New gen GTR comes with only an autobox.
Higher up the food chain the mightt Astons/Ferraris going all paddle shifters ?
Future doesn't look good.
Thursday 29 September 2011
Horsepower means nothing, dont buy a car just because it has a higher Bhp/PS number
Car 1 has 20 BHP more than car2 .. simple, car1 has more power definately its faster.
They weigh approximately the same etc.
if you are an enthusiast that just about sounds like the right recipie.
I too used to compare the BHP figures and think that more power is better.
This not just applies to buying cars but also aftermarket modifications and tuning.
If you are the techie types - you may even look at the manufacturer's or tuner's dyno chart to confirm which car has more power.
Guys there is more to it -much more.
Lets start with the basics :
1] Engines dont make BHP. Period. Engines make torque.
2] The pistons convert the Air/Fuel explosion into downward motion, the crank converts this "kick" into rotational motion. This rotational motion turns your fly wheel, the gearbox connects to flywheel via the clutch and transfers power to the wheels which then rotate.
3] The important point in the above point is rotational force generated by the engine. This is torque in a simplified description.
4] What about BHP ? oh ya forgot about that - its calculated off the torque..
hp = [torque x rpm ] / 5252
The combination of torque and rpm results in power..
5]Simply put - going faster means accelarating harder and quickly. It's this rate of change of speed gives us accelaration = faster car.
6]BHP advertised is always the max power that can be generated by an engine, the question we should be asking is at what rpm ? i.e at what speed the engine must be running at to actually use this power ?
Remember point no 4 , Hp= resultant of rpm and torque.
We could be getting 300 bhp at say 6800 rpm from car1 Vs 240 bhp @ 5500 rpm from car2
Here we need to ask 3 questions:
(a) How long does it take to reach this 6800 rpm as its way up in the rpm range ?
It takes time to build up this rpm, you could end up spending more time waiting to reach this high engine speed only after which you would experience this power..Also during every gear change the engine rpm would drop and again you would spend time building up the speed to reach that range.
Its like climbing a mountain for 8hrs, reaching the peak and spending 2 minutes at the peak before sliding off.. and again having to restart from teh base of he mountain.
HP figures dont give the whole picture.
(b) Even if we manage to reach it , how long can we use this power ?
This means once you manage to reach this engine speed/rpm what next? You have spent some time reaching this rpm how long will it last? For how long can you mantain that rpm to harness this power ?
On road/track is it practical ? You may have to brake, take corners etc causing the rpm to drop again below the number at which we get peak power.
Also if you give too much throttle you may exceed the rpm the engine makes the most power and engine will be only making noise not power therfore not accelarating.
The width of the power band also matters combined with your gearing and final drive. This is what determines how long will you be riding that wave of torque and accelarating hard.
This advertised power is peak power, it doesn't tell us the whole story
Gearing/Final drive/Tyre size +Power/Wt ratio :
Many aftermarket tuners enthusiasts look at dyno numbers and get impressed if they see a 10-20 bhp bump in power. This is not an indicator of how much performance will be realised on the road.
It depends on your gearing ratio/final drive/tyre size combination to lay down that "power(actually is torque)" of engine on the road...
Let me explain this with an example - Car C1 with same engine but with diff gearing and tyres makes hell of a difference. E.g if the power band is near 4000 rpm, having torque of 150 Nm at 4000 rpm and engine makes 130 bhp at say 5500 rpm, the gearing and stock tyre size allows the car to travel at 80Kmh/50Mph at say 3000 rpm. With a smaller tyre size and a lower gear ratio the same car at 4000 rpm now travels at 80Kmh/50 mph. See now the engine is in the power band and will respond to quick blip of the throttle.
Now taking the same car and comparing it to another car say C2 with power of 200 bhp @ 6000 rpm, torque of 180NM at 5000 rpm.
The difference in power is 70 BHP - based on BHP specs we have a winner, car C2 wins on paper
The difference in torque is 30 NM - based on torque specs we have a winner,car C2 wins.on paper
But based on gearing and overall wt of the car C2 is a loser against C1.
C1's gearing and torque has been optimised to make max use of the engines torque and does not lay stress on the peak hp figures.. its just a marketting gimmick.
99.99 % of the people look at the HP and pay extra 10 to 20K$ for this.
Dont beleive me - look at a real world example.
BMW M1 vs BMW M3
M1= 335 BHP, 6 cylinder, 3000 cc, price :46K $
M3= 414 BHP,8 cylinders, 4000 cc, price :58K $
Price of M3 justified : 79 more bhp, extra 1000 cc, extra 2 cylinders..therefore extra 12k $
Track tested by BBC Top gear : results M1 is much faster, track is designed to test the real world accelaration, handling, braking.. a bit of brute force power also.
How did it manage to do that -->
M1 makes 332 NM of torque from 1500 rpm to 4500 rpm, supposedly bigger, powerful, more expensive M3 makes 295 NM of torque at 3900 rpm
The M1 can pull; anytime anywhere.. people just dont get it.
Along same lines no one belives If I said a slightly modified 50 BHP 3 cylinder, 800 cc, 4 valve SOHC, 600 Kg hatchback can mess with 70 to 90 bhp , 4 cylinder, 1100 cc to 1300 cc engines.. :-) or even 2600 cc diesel SUVs :-)
They weigh approximately the same etc.
if you are an enthusiast that just about sounds like the right recipie.
I too used to compare the BHP figures and think that more power is better.
This not just applies to buying cars but also aftermarket modifications and tuning.
If you are the techie types - you may even look at the manufacturer's or tuner's dyno chart to confirm which car has more power.
Guys there is more to it -much more.
Lets start with the basics :
1] Engines dont make BHP. Period. Engines make torque.
2] The pistons convert the Air/Fuel explosion into downward motion, the crank converts this "kick" into rotational motion. This rotational motion turns your fly wheel, the gearbox connects to flywheel via the clutch and transfers power to the wheels which then rotate.
3] The important point in the above point is rotational force generated by the engine. This is torque in a simplified description.
4] What about BHP ? oh ya forgot about that - its calculated off the torque..
hp = [torque x rpm ] / 5252
The combination of torque and rpm results in power..
5]Simply put - going faster means accelarating harder and quickly. It's this rate of change of speed gives us accelaration = faster car.
6]BHP advertised is always the max power that can be generated by an engine, the question we should be asking is at what rpm ? i.e at what speed the engine must be running at to actually use this power ?
Remember point no 4 , Hp= resultant of rpm and torque.
We could be getting 300 bhp at say 6800 rpm from car1 Vs 240 bhp @ 5500 rpm from car2
Here we need to ask 3 questions:
(a) How long does it take to reach this 6800 rpm as its way up in the rpm range ?
It takes time to build up this rpm, you could end up spending more time waiting to reach this high engine speed only after which you would experience this power..Also during every gear change the engine rpm would drop and again you would spend time building up the speed to reach that range.
Its like climbing a mountain for 8hrs, reaching the peak and spending 2 minutes at the peak before sliding off.. and again having to restart from teh base of he mountain.
HP figures dont give the whole picture.
(b) Even if we manage to reach it , how long can we use this power ?
This means once you manage to reach this engine speed/rpm what next? You have spent some time reaching this rpm how long will it last? For how long can you mantain that rpm to harness this power ?
On road/track is it practical ? You may have to brake, take corners etc causing the rpm to drop again below the number at which we get peak power.
Also if you give too much throttle you may exceed the rpm the engine makes the most power and engine will be only making noise not power therfore not accelarating.
The width of the power band also matters combined with your gearing and final drive. This is what determines how long will you be riding that wave of torque and accelarating hard.
This advertised power is peak power, it doesn't tell us the whole story
Gearing/Final drive/Tyre size +Power/Wt ratio :
Many aftermarket tuners enthusiasts look at dyno numbers and get impressed if they see a 10-20 bhp bump in power. This is not an indicator of how much performance will be realised on the road.
It depends on your gearing ratio/final drive/tyre size combination to lay down that "power(actually is torque)" of engine on the road...
Let me explain this with an example - Car C1 with same engine but with diff gearing and tyres makes hell of a difference. E.g if the power band is near 4000 rpm, having torque of 150 Nm at 4000 rpm and engine makes 130 bhp at say 5500 rpm, the gearing and stock tyre size allows the car to travel at 80Kmh/50Mph at say 3000 rpm. With a smaller tyre size and a lower gear ratio the same car at 4000 rpm now travels at 80Kmh/50 mph. See now the engine is in the power band and will respond to quick blip of the throttle.
Now taking the same car and comparing it to another car say C2 with power of 200 bhp @ 6000 rpm, torque of 180NM at 5000 rpm.
The difference in power is 70 BHP - based on BHP specs we have a winner, car C2 wins on paper
The difference in torque is 30 NM - based on torque specs we have a winner,car C2 wins.on paper
But based on gearing and overall wt of the car C2 is a loser against C1.
C1's gearing and torque has been optimised to make max use of the engines torque and does not lay stress on the peak hp figures.. its just a marketting gimmick.
99.99 % of the people look at the HP and pay extra 10 to 20K$ for this.
Dont beleive me - look at a real world example.
BMW M1 vs BMW M3
M1= 335 BHP, 6 cylinder, 3000 cc, price :46K $
M3= 414 BHP,8 cylinders, 4000 cc, price :58K $
Price of M3 justified : 79 more bhp, extra 1000 cc, extra 2 cylinders..therefore extra 12k $
Track tested by BBC Top gear : results M1 is much faster, track is designed to test the real world accelaration, handling, braking.. a bit of brute force power also.
How did it manage to do that -->
M1 makes 332 NM of torque from 1500 rpm to 4500 rpm, supposedly bigger, powerful, more expensive M3 makes 295 NM of torque at 3900 rpm
The M1 can pull; anytime anywhere.. people just dont get it.
Along same lines no one belives If I said a slightly modified 50 BHP 3 cylinder, 800 cc, 4 valve SOHC, 600 Kg hatchback can mess with 70 to 90 bhp , 4 cylinder, 1100 cc to 1300 cc engines.. :-) or even 2600 cc diesel SUVs :-)
WTF were they thinking : BOSS 302 - whats the point has it lost its identity?
Whats up with Ford ? cant they get anything right ever ?
Lots of people maybe raving about the new Boss, ok fine it beat the M3 on the track @ Laguna Seca..
Great job Ford...
Now for some other points for some pure Ford's awesomeness:
1] 2 keys ? Blue for regular use and Red for race/track mode:
My thoughts -
[a]LOL , whats up Ford ? copying BMW's M ideas /Honda's Vtec ?
- BMW always had an "M" button to switch between 2 maps for fuelling,ignition, throttle response, suspension etc
-Honda always had vtec , floor it and above 5800 rpm hell breaks loose, diff cam profile, fuelling and ignition curves..
.. I'd summarize this feature as "Yawn".. Ford u guys were always boring and no matter how hard u try u will never get the point.
[b]Another point of view these morons didnt consider - and this is my favourite..
Lets picture this - you are crusing along with the blue key, but along the way you encounter a nice hilly stretch of road with no traffic, naturally you'd want to flex the v8's muscles and see what its got; or another scenario where you'd want to kick a ricer's ass and need to show him who's the Boss .. If I was in a smarter engineered car I would press a button or floor the throttle or simple downshift to unleash power.
Hey but im in a Ford !! Guess what boys and girls what do the Boss owners do ?
Please raise your hands if u think u got the right answer:
Hahahah - Pull over, search for a spot to get off the expressway, switch of your engine and swap the keys or if you are brave or on medication you could attempt to put car in neutral and see if you switch off and swap keys ..
Nice idea - lots of thought must have gone into this awesome innovation.
Red key ..my ass ..morons.
2] Live rear axleC'mon guys, "free online suspension design lesson" for you - please write this down:
Good handling = Not live rear axle, anything but this.
Bad handling = Live rear axle
Guys we usually use some thing called a "independant suspension" on cars..please google it to get an idea of what it does.Hey even some offroaders are moving away from Solid axles to independant suspensions..
Hey who know we may need to do some rock climbing along with the jeeps ..probably would be useful there.
3] Quad pipes : Not buying this gimmick.
How did you design an exhuast header ? was it for the baffle plates closed or open ?
Did u design it with both in mind ?
total compromise of both low end and top end power..
I dont even want to think what happens to the velocity of the exhaust pulses when the baffles are opened ?
Turbulence - like a washing machine..
Exhaust/Header design lesson 1 - mantain exhaust velocity, turbulence = bad.
Unless you are out to design a rice machine..
Also it sounds like the exhaust is cracked/broken ..doesnt sound impressive at all.
4] Front splitter Guys - u are more rice than a mexican in a civic.
Front splitter which is like 1/2 a foot of the ground .. LOL
Even if you lower the car with adjustable shocks ..the overall truck lile aerodynamics are going to kill the whole point of the lowering + splitter etc.
Im now even more sure this car is for the posers/newbies wanting to buy a performance car out of the box..but will end up with a rice aerodynmic body kit.
My fav line - Front splitter ..my ass.
5] 380 lb/ft. @4,500 rpm Let me break this down into simplified terms and what it means to the driver while driving the car on a daily basis.
[1]Consider the gear ratios of the Boss302:
First 3.66
Second 2.43
Third 1.69
Fourth 1.32
Fifth 1.00
Sixth 0.65
[2]And a Final drive 3.73:1
[3] Tyre sizes as provided by the factory : 255/40R-19 or 285/35R-19
Now the most important question :
Considering the gear ratios and final drive with 19 inch wheels with 40 Profile can we really use that 380 lb/foot of torque at 4600 rpm.
--> 380 lb/ft = 514 NM in metric.
i.e 514 NM @ 4600 rpm
E.g normal road cars usually cruise at 2500 to 3500 rpm on freeways..
At these speeds the boss 302 engine is outside of its power band.
At 2500 Rpm the road speeds are calculated as :
1st gear :15mph
2nd gear :22mph
3rd gear :32mph
4th gear :41mph
5th gear :54mph
6th gear :82mph
Seems a bit slow, lets try 3500 rpm
1st gear :20mph
2nd gear :31mph
3rd gear :44mph
4th gear :57mph
5th gear :75mph
6th gear :115mph
Ok this seems reasonable, Im tying to cruise @ respectable speeds in CA..
I'm able to remain in 5th gear and do 75 mph @ 3500 rpm..not going to over drive coz I want to retain the capability to quickly overtake and change lanes ...
Observation - Im no where near the power band, Im not using the 512 NM as yet.
Now if I really wanted to use it I'd have to travel at 4500 rpm, so If I tap the throttle and climb to 4500 rpm what happens to my road speed?
Here are the figures with respect to gearing/final drive tyre etc etc
1st gear :26mph
2nd gear :40mph
3rd gear :57mph
4th gear :73mph
5th gear :96mph
6th gear :148mph
Oh no - dangerously into the speeding ticket zone.
So I will need to downshift to 4th to be able to ride the torque wave..
To understand what that feels like, just try and reach 4500 rpm in ur current car just to see how high that is..
..This makes it clear what this engine+gear bix+final drive +tyre combination means:
Its not a muscle car anymore,
Ford u got it wrong again - the Boss should be a torque monster not a screamer to carry its own heavy ass around.
With a kerb weight of 3600 pounds = 1632 kg = 1.6 tonnes ..
I need torque from down below from 1500/1800 rpm to haul this 1.6 tonnes of flab to respectable speeds and be able to cruise the way an "American muscle" car should.
Ideally a Muscle car = Heavy sedan/coupe with a massive V8 with a brutal bulldozer like shove of torque from way down in the rev range.and not a 7500 rpm screamer...
Hey V8s are not screamers ..leave the hi revs to the Wankels and Vtecs.
concentrate on width of power band instead of peak figures becoz the 302 is no agile/light wt sports car to simply point and shoot with the tacho at 6500 rpm.
Wake up guys and go back to the drawing board.
512 NM ..my ***
Lots of people maybe raving about the new Boss, ok fine it beat the M3 on the track @ Laguna Seca..
Great job Ford...
Now for some other points for some pure Ford's awesomeness:
1] 2 keys ? Blue for regular use and Red for race/track mode:
My thoughts -
[a]LOL , whats up Ford ? copying BMW's M ideas /Honda's Vtec ?
- BMW always had an "M" button to switch between 2 maps for fuelling,ignition, throttle response, suspension etc
-Honda always had vtec , floor it and above 5800 rpm hell breaks loose, diff cam profile, fuelling and ignition curves..
.. I'd summarize this feature as "Yawn".. Ford u guys were always boring and no matter how hard u try u will never get the point.
[b]Another point of view these morons didnt consider - and this is my favourite..
Lets picture this - you are crusing along with the blue key, but along the way you encounter a nice hilly stretch of road with no traffic, naturally you'd want to flex the v8's muscles and see what its got; or another scenario where you'd want to kick a ricer's ass and need to show him who's the Boss .. If I was in a smarter engineered car I would press a button or floor the throttle or simple downshift to unleash power.
Hey but im in a Ford !! Guess what boys and girls what do the Boss owners do ?
Please raise your hands if u think u got the right answer:
Hahahah - Pull over, search for a spot to get off the expressway, switch of your engine and swap the keys or if you are brave or on medication you could attempt to put car in neutral and see if you switch off and swap keys ..
Nice idea - lots of thought must have gone into this awesome innovation.
Red key ..my ass ..morons.
2] Live rear axleC'mon guys, "free online suspension design lesson" for you - please write this down:
Good handling = Not live rear axle, anything but this.
Bad handling = Live rear axle
Guys we usually use some thing called a "independant suspension" on cars..please google it to get an idea of what it does.Hey even some offroaders are moving away from Solid axles to independant suspensions..
Hey who know we may need to do some rock climbing along with the jeeps ..probably would be useful there.
3] Quad pipes : Not buying this gimmick.
How did you design an exhuast header ? was it for the baffle plates closed or open ?
Did u design it with both in mind ?
total compromise of both low end and top end power..
I dont even want to think what happens to the velocity of the exhaust pulses when the baffles are opened ?
Turbulence - like a washing machine..
Exhaust/Header design lesson 1 - mantain exhaust velocity, turbulence = bad.
Unless you are out to design a rice machine..
Also it sounds like the exhaust is cracked/broken ..doesnt sound impressive at all.
4] Front splitter Guys - u are more rice than a mexican in a civic.
Front splitter which is like 1/2 a foot of the ground .. LOL
Even if you lower the car with adjustable shocks ..the overall truck lile aerodynamics are going to kill the whole point of the lowering + splitter etc.
Im now even more sure this car is for the posers/newbies wanting to buy a performance car out of the box..but will end up with a rice aerodynmic body kit.
My fav line - Front splitter ..my ass.
5] 380 lb/ft. @4,500 rpm Let me break this down into simplified terms and what it means to the driver while driving the car on a daily basis.
[1]Consider the gear ratios of the Boss302:
First 3.66
Second 2.43
Third 1.69
Fourth 1.32
Fifth 1.00
Sixth 0.65
[2]And a Final drive 3.73:1
[3] Tyre sizes as provided by the factory : 255/40R-19 or 285/35R-19
Now the most important question :
Considering the gear ratios and final drive with 19 inch wheels with 40 Profile can we really use that 380 lb/foot of torque at 4600 rpm.
--> 380 lb/ft = 514 NM in metric.
i.e 514 NM @ 4600 rpm
E.g normal road cars usually cruise at 2500 to 3500 rpm on freeways..
At these speeds the boss 302 engine is outside of its power band.
At 2500 Rpm the road speeds are calculated as :
1st gear :15mph
2nd gear :22mph
3rd gear :32mph
4th gear :41mph
5th gear :54mph
6th gear :82mph
Seems a bit slow, lets try 3500 rpm
1st gear :20mph
2nd gear :31mph
3rd gear :44mph
4th gear :57mph
5th gear :75mph
6th gear :115mph
Ok this seems reasonable, Im tying to cruise @ respectable speeds in CA..
I'm able to remain in 5th gear and do 75 mph @ 3500 rpm..not going to over drive coz I want to retain the capability to quickly overtake and change lanes ...
Observation - Im no where near the power band, Im not using the 512 NM as yet.
Now if I really wanted to use it I'd have to travel at 4500 rpm, so If I tap the throttle and climb to 4500 rpm what happens to my road speed?
Here are the figures with respect to gearing/final drive tyre etc etc
1st gear :26mph
2nd gear :40mph
3rd gear :57mph
4th gear :73mph
5th gear :96mph
6th gear :148mph
Oh no - dangerously into the speeding ticket zone.
So I will need to downshift to 4th to be able to ride the torque wave..
To understand what that feels like, just try and reach 4500 rpm in ur current car just to see how high that is..
..This makes it clear what this engine+gear bix+final drive +tyre combination means:
Its not a muscle car anymore,
Ford u got it wrong again - the Boss should be a torque monster not a screamer to carry its own heavy ass around.
With a kerb weight of 3600 pounds = 1632 kg = 1.6 tonnes ..
I need torque from down below from 1500/1800 rpm to haul this 1.6 tonnes of flab to respectable speeds and be able to cruise the way an "American muscle" car should.
Ideally a Muscle car = Heavy sedan/coupe with a massive V8 with a brutal bulldozer like shove of torque from way down in the rev range.and not a 7500 rpm screamer...
Hey V8s are not screamers ..leave the hi revs to the Wankels and Vtecs.
concentrate on width of power band instead of peak figures becoz the 302 is no agile/light wt sports car to simply point and shoot with the tacho at 6500 rpm.
Wake up guys and go back to the drawing board.
512 NM ..my ***
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