Understanding models - power and MHEV

[Nismex]

Don’t let it not being a mild hybrid put you off, the 125 standard engine is better imho, goes very well and better than the mild hybrid. When the minuscule battery runs out it is down on power over the none hybrid, which actually is most of the time! Your lucky you’ve found a none hybrid, snap it up ! And being a Ford, less to go wrong in the near future.

The slight less eager pick up is because it’s petrol not diesel so needs a few more revs for the turbo to spin up, thru certainly aren’t sluggish so I suspect you were driving it as a diesel, changing gear far to early. You need to keep the 1.0 above 1500 at all times for best results.

Why would the ICE be down on power when the hybrid battery is depleted?

I might be wrong but I thought they changed a few things with the hybrid drivetrain, like change to compression ratio and larger/optimised turbo, I think Ford shifted the efficiency higher in the rpm range and utilised the electric motor assist for the low speed.

[Vendee]

Don’t let it not being a mild hybrid put you off, the 125 standard engine is better imho, goes very well and better than the mild hybrid. When the minuscule battery runs out it is down on power over the none hybrid, which actually is most of the time! Your lucky you’ve found a none hybrid, snap it up ! And being a Ford, less to go wrong in the near future.

The slight less eager pick up is because it’s petrol not diesel so needs a few more revs for the turbo to spin up, thru certainly aren’t sluggish so I suspect you were driving it as a diesel, changing gear far to early. You need to keep the 1.0 above 1500 at all times for best results.

Why would the ICE be down on power when the hybrid battery is depleted?

I might be wrong but I thought they changed a few things with the hybrid drivetrain, like change to compression ratio and larger/optimised turbo, I think Ford shifted the efficiency higher in the rpm range and utilised the electric motor assist for the low speed.

You may well be right there. The mapping may be different. It would be interesting to know if there was any change to the turbo or the compression ratio.

[Civpilot]

Don’t let it not being a mild hybrid put you off, the 125 standard engine is better imho, goes very well and better than the mild hybrid. When the minuscule battery runs out it is down on power over the none hybrid, which actually is most of the time! Your lucky you’ve found a none hybrid, snap it up ! And being a Ford, less to go wrong in the near future.

The slight less eager pick up is because it’s petrol not diesel so needs a few more revs for the turbo to spin up, thru certainly aren’t sluggish so I suspect you were driving it as a diesel, changing gear far to early. You need to keep the 1.0 above 1500 at all times for best results.

Nothing you have said is correct.

The mild hybrid power output is not included in the cars power rating as stated. The 125 MHEV engine has 125ps from the petrol engine alone. The hybrid assistance is a separate power figure and only used for toque fill low down the rev range as the engine spools up. It’s not power added on the top end at all. It’s this hybrid assistance that is the difference in performance between the non hybrid and hybrid engine (nothing to do with petrol type).

And you cannot deplete the hybrid battery as it is constantly charging itself every single time you are off the throttle. And if you could deplete the battery in the hybrid 125 you would end up with exactly the same (sluggish) performance as the non hybrid 125. It doesn’t go anywhere near as well as the MHEV engine. Nowhere near.

Guy I work with has a non hybrid ecoboost puma and compared to my 155MHEV it feels like it’s got its handbrake on. Even in eco mode the MHEV is quicker to build speed. It’s actually a similar story when comparing it to the 125MHEV. They feel like different cars

Maybe read up on how the MHEV actually works before stating facts about it.

To the OP…. Having driven both engine types my advice would be to avoid the non MHEV engine like the plague. It’s sluggish, slow, and not as efficient. It’s just not worth the money. If you can’t stretch to a proper MHEV then buy a different cheaper car because as soon as you drive the MHEV equipped puma you will regret your choice.

[4251]

Most of the time the battery will be useless for any significant boost. During this time the battery and motor are excess baggage wasting power and fuel made worse when the engine decides to waste fuel charging it. Often making the overall effect less than the standard engine. Comparing 125 to 125, 155 is irrelevant. I have driven both over a significant distance and preferred the none hybrid and it got slightly better mpg, albeit both were crap for a 1.0 litre engined little car. About 40 at best. Our 200hp NONE hybrid 50% bigger engined ST manages that driving it much faster, and feels twice as fast 6.5 seconds to 60 not 10 seconds, the 155 is still nearly 9 seconds with its super electric boost, 1980’s 105hp naturally aspirated Escort XR3 performance, pretty poor considering the mhev claims

[Vendee]

During this time the battery and motor are excess baggage wasting power and fuel made worse when the engine decides to waste fuel charging it.

And that statement demonstrates that you don't understand how the system works. The hybrid battery charges when you come off the throttle. The engine isn't wasting fuel or even using fuel.

[4251]

During this time the battery and motor are excess baggage wasting power and fuel made worse when the engine decides to waste fuel charging it.

And that statement demonstrates that you don't understand how the system works. The hybrid battery charges when you come off the throttle. The engine isn't wasting fuel or even using fuel.

Oh really? Unless it’s different to others…. The ecu chooses how to charge the battery, it can and does use the engine to charge the battery via the starter generator, as it must maintain a certain level of charge for starting which it often won’t get enough off from braking and coasting!!! They don’t pedal that in their explanations for obvious reasons , but it is used. That’s part of the reason in real world they prove no better on fuel economy. They can be better under ideal situations, unfortunately the real driving world doesn’t provide them most of the time. It’s a technology that benefits the wltp approval test far more than the end user. But also good for drawing in the gullible. 0-60 times are almost identical between 125 mhev and normal 125 and that’s certainly what I experienced. Wouldn’t opt for it, given a choice.

[4251]

Oh, hang on a bit….. as far as I am aware they don’t have an alternator? The bumph says the starter generator replaces the starter motor and alternator ! I or the bumph could be wrong as I have little interest in them? If so that “motor generator” is being driven by the engine all of the time, or most of it to power the cars 12 volt very significant loads only being aided by coasting and braking regen. Or could someone explain how the cars 12v electrics are powered, fairy dust maybe?

[4251]

Yes, the BISG (starter generator) charges and runs the 12v system in place of a conventional alternator, so it is constantly acting as a generator under load. A DC/DC convertor, converts the 48v DC to 12v DC to charge and run the 12v car systems, this is a very significant constant load as in any modern car. In the case of the Ford system the (more accurate) bumph I’ve read says it still also has a 12v conventional starter motor fitted (others don’t) to back up the BISG for cold starting and I guess if the lithium 48v battery is too low or just simply it won’t last long if the car has starting difficulties.

The BISG fitted to the ST170 has an output of 11.5KW that is approx 15.6HP. Not been able to confirm if the power claims for the mhev’s includes this figure (Going by the 0-62 figures of the 170ST of 7.5 seconds I would expect it to?) but the information is cack.

Going by the vague spec available the motor will draw approx 240 amps at full load, the battery appears to be only 8ah. So if this is fully charged it will run the motor at full load (15.6hp) for a maximum of 2 minutes before being fully depleted, however it wouldn’t be allowed to be fully depleted for reasons above, so more likely about 1min of full power is available before it will be terminated and charged. You will need a lot of coasting/slowing to maintain much in the way of efficiency. Hence little if any difference to economy a lot of the time.

So to summarise: there’s a lot more (and less!) going on than shown in Ford’s silly marketing cartoon !

[Civpilot]

Yes, the BISG (starter generator) charges and runs the 12v system in place of a conventional alternator, so it is constantly acting as a generator under load. A DC/DC convertor, converts the 48v DC to 12v DC to charge and run the 12v car systems, this is a very significant constant load as in any modern car. In the case of the Ford system the (more accurate) bumph I’ve read says it still also has a 12v conventional starter motor fitted (others don’t) to back up the BISG for cold starting and I guess if the lithium 48v battery is too low or just simply it won’t last long if the car has starting difficulties.

The BISG fitted to the ST170 has an output of 11.5KW that is approx 15.6HP. Not been able to confirm if the power claims for the mhev’s includes this figure (Going by the 0-62 figures of the 170ST of 7.5 seconds I would expect it to?) but the information is cack.

Going by the vague spec available the motor will draw approx 240 amps at full load, the battery appears to be only 8ah. So if this is fully charged it will run the motor at full load (15.6hp) for a maximum of 2 minutes before being fully depleted, however it wouldn’t be allowed to be fully depleted for reasons above, so more likely about 1min of full power is available before it will be terminated and charged. You will need a lot of coasting/slowing to maintain much in the way of efficiency. Hence little if any difference to economy a lot of the time.

So to summarise: there’s a lot more (and less!) going on than shown in Ford’s silly marketing cartoon !

The overall power figure quoted by Ford is the petrol engine on its own not the hybrid assistance included. The hybrid assistance only comes in low down the rev range hence why the hybrid accelerates faster than the standard petrol engine. Peak power at max revs (Where the quoted power output is recorded ) doesn’t really make a lot of difference to your acceleration of the line, it’s lowdown torque and how the power is delivered that mainly effects acceleration. The quicker acceleration in the MHEV is due to the fact that all of the assistance is delivered at the bottom of the rev range. The engine peak power is identical to the non-hybrid and as recorded by Ford. (it’s the reason why figures for the MHEV assistance are not often quoted. It’s because they don’t make a difference to peak output).

The hybrid assistance kicks in very low down the rev range and a basically ‘torque fills’ while the engine spins up to speed. Once you get near to the top of the rev range, the hybrid assistance does nothing and it’s nothing to overall BHP. Lots of plug in hybrid cars behave pretty much the same way and pretty much every self charging mild hybrid behaves 100% the same way.

Another way the MHEV engine is better is the regenerative braking. By using this method to regain power into the battery it also means the car is lighter on its brake pads. When you get off the throttle. If you have a nice clear road and good anticipation you can pretty much let the car slow itself down all the way to a standstill (as long as you remember to dip the clutch at the last minute). Whenever I wash the car, there’s absolutely minimal brake dust on the alloy wheels compared to a normal car.

You seem utterly convinced that, somehow the 125 hp eco-boost engine is more efficient and better than the hybrid. It’s absolutely not. Every figure and metric recorded for the car either by Ford or by independent road testers clearly shows this.
Anyone who has driven both the non-hybrid and the hybrid can clearly tell you this.

I’ve owned a non-hybrid 125 eco-boost engine in a much lighter car (fiesta) and I can tell you it’s nowhere near as efficient as the (heavier) Puma 155 hybrid. It’s also nowhere near the performance or tractability. My friend has the 125 hybrid puma and she gets better MPG and acceleration than I used to get in my fiesta.

I’m guessing you bought the non-hybrid car and are trying to justify your choice. 125 Eco boost is a fine engine. It’s just not as good as the MHEV version. Quite simple.

[Stoopo]

My understanding is that the 155 has a bigger turbo which is facilitated by the car being a mild hybrid. The electric motor allows this and negates ant turbo lag that would otherwise be present.

The 125 engine by itself is fairly quick. I’ve had it in my previous Focus and my mate has just had it in his Focus Active X. You need to use the gears more but it’s fast enough for most drivers.

That’s said my 155 is much quicker. I personally wouldn’t drop back to a 125 now - MhEV or not.

To the OP. Have you checked Cazoo? They have some good deals and will deliver too.