RE: Chris Harris video: M135i vs A45 AMG

RE: Chris Harris video: M135i vs A45 AMG

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Discussion

AlexS

1,552 posts

233 months

Wednesday 24th July 2013
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RobM77 said:
kambites said:
Lowtimer said:
kambites said:
I've never driven an EFI engine that I've been entirely happy with the throttle response of; they all seem to have a bit of delay (including my Elise, it's one of the most annoying things about its controls).

The difference between the Elise and the MGB is nowhere near as stark as between the Octavia and the Elise, but it's still fairly noticeable if you drive the two back-to-back.
Modern factory EFI is like that, agreed, but mechanical injection systems can be delicious, and anything from the Bosch K-Jetronic era can be excellent too. In general I think the best possible layout for pure throttle response is cable throttle, properly mapped electronic ignition, mechanical injection. For example a nicely set-up '70s Porsche 911E
I'd add ITBs to that list. Also carburettors can be as good as (but probably no better than) mechanical fuel injection but again, you need one carb per cylinder, mounted as close to the inlet valve as possible.

Anyway, this is a little off topic. I don't think BMW or Mercedes are going to go out and build us an MFI, cable throttled, ITB, normally aspirated hot hatch. hehe

Edited by kambites on Tuesday 23 July 11:53
Nope, but they could concentrate on throttle response more than they do. If they can make the E92 M3's 4 litre V8 with decent throttle response then why not the 335i, 330i etc? OK, so there's probably an engineering reason why, but it can't be impossible to change things to remove that lag. My old 330ci was so bad that you could stamp your foot up and down on the throttle in 1st gear and nothing happened. For a company whose selling point is how much better to drive their cars are than the competition, I think it's unacceptable to have a lag on the throttle. I currently avoid the problem by driving one of their diesels, but I'd dearly love to get one of their petrol straight six cars again (of which I've had four out of five BMWs owned).
Carbs are dreadful unless you want to operate over a very narrow rev range. You also get issues if you want to run a lumpy cam at lowish engine rpm. The pulses back up the inlet confuse the carb and the fuelling goes to pot. On the other hand, fuel injection will correct over the complete rev range.

A lot of the throttle reponse issues come from minimising emissions. IIRC slowly opening the throttle reduces NOx.

Mr Whippy

29,086 posts

242 months

Wednesday 24th July 2013
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GranCab said:
Progress ?

E55 AMG I bought new in 1998 @ circa £60,000 ... 5.4 24V AMG V8 354 PS (260 kW; 349 hp) 530 N·m (391 lb·ft) 0- 62 mph 5.4 secs

A45 AMG can be bought new for circa £38,000 ... 2.0 AMG in-line 4cyl 360 PS (265 kW; 355 hp) @6000, 450 N·m (332 lbf·ft) @2250-5000 0-62mph: 4.6 seconds
But the 2.0 will be laggy and sound crap vs the V8.

I bet economy when 'using it' isn't that much better either.

Also there were big power 2.0 turbo engines in 1998. Most Evo VI's could be easily breathed on to make 350bhp and 300lbft without breaking a sweat.


The only thing those old engines didn't do is emphasise economy because no one who buys that kinda car anyway really cares about mpg... not that much any way. Only the government and their tax approach cares which is why buyers care today.


I'll admit we have progressed, but not as much as you'd think. We simply care about more irrelevant numbers these days and using those new fairly pointless metrics new cars are better.


Thankfully we can tinker with electrics more than ever and put right a lot of the tuned in wrongness in new cars to make them good again biggrin

Dave

RobM77

35,349 posts

235 months

Wednesday 24th July 2013
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The Crack Fox said:
These videos are great, but are waaaaaaaaaaaaaaay too long, cut the waffle and get it down to 5 minutes !

smile
I like the waffle! smile

FamilyDub

3,587 posts

166 months

Wednesday 24th July 2013
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RobM77 said:
I like the waffle! smile
^ Me too! I think that's what actually sets Harris' videos apart from the rest.

carinaman

21,335 posts

173 months

Wednesday 14th August 2013
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Not a video, but includes the Audi S3:

http://www.carmagazine.co.uk/Drives/Search-Results...

DonkeyApple

55,570 posts

170 months

Thursday 15th August 2013
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carinaman said:
Not a video, but includes the Audi S3:

http://www.carmagazine.co.uk/Drives/Search-Results...
A poor analogy:

'The 135i will want to understeer into a corner and oversteer at the exit, but the Audi goes round bends like a slot racer with a second pin between the rear wheels'

No one would buy that slot racer as it defeats the entire reason for the product's existence.

On a serious note. They keep referring to 10/10s pace. Up in the Dolomites? They can't have been been driving these 10/10s on public roads let alone up there?

Given how so many car's character changes quite distinctly between the 7/8 tenths a very good driver might be capable of on the roads and the 10 tenths a good racer can achieve on track this would make for quite a difference in inference in this article.

Edited by DonkeyApple on Thursday 15th August 08:24

scherzkeks

4,460 posts

135 months

Thursday 15th August 2013
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DonkeyApple said:
A poor analogy:

'The 135i will want to understeer into a corner and oversteer at the exit, but the Audi goes round bends like a slot racer with a second pin between the rear wheels'

No one would buy that slot racer as it defeats the entire reason for the product's existence.

On a serious note. They keep referring to 10/10s pace. Up in the Dolomites? They can't have been been driving these 10/10s on public roads let alone up there?

Given how so many car's character changes quite distinctly between the 7/8 tenths a very good driver might be capable of on the roads and the 10 tenths a good racer can achieve on track this would make for quite a difference in inference in this article.

Edited by DonkeyApple on Thursday 15th August 08:24
They are saying the car is neutral. I would interpret the "slot racer" comment as quite positive, since neutral cornering behavior is ideal for going fast.

DonkeyApple

55,570 posts

170 months

Thursday 15th August 2013
quotequote all
scherzkeks said:
They are saying the car is neutral. I would interpret the "slot racer" comment as quite positive, since neutral cornering behavior is ideal for going fast.
A agree but the analogy is out of place. They have used a comparison where to pin both front and rear down totally ruins the product and makes it pointless. This is not what they meant.

I think he was trying to avoid using the term 'corner like on rails' and chose the wrong alternative. It's not really a relevant issue though as you know what he was trying to say and he was trying to inject an element of 'manicness'. Or was he?

FamilyDub

3,587 posts

166 months

Thursday 15th August 2013
quotequote all
scherzkeks said:
I would interpret the "slot racer" comment as quite positive, since neutral cornering behavior is ideal for going fast.
^ I assumed the opposite.

Through all these comparison tests I still think a slower M135i > A45.

Johnnytheboy

24,498 posts

187 months

Thursday 15th August 2013
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The more comparative reviews I'm reading the more I'm concluding that the A45 would be the far better car if you could constantly drive it like you stole it. The M135i would be better all the rest of the time. I think I'm showing my age by thinking that makes the BMW better for me.


DonkeyApple

55,570 posts

170 months

Thursday 15th August 2013
quotequote all
Johnnytheboy said:
The more comparative reviews I'm reading the more I'm concluding that the A45 would be the far better car if you could constantly drive it like you stole it. The M135i would be better all the rest of the time. I think I'm showing my age by thinking that makes the BMW better for me.
I agree. And at our age we are at high risk of slipping a disk every time you get out if the AMG and then quickly lunge back in to grab the satnav you've left on the dash. biggrin

Johnnytheboy

24,498 posts

187 months

Thursday 15th August 2013
quotequote all
DonkeyApple said:
Johnnytheboy said:
The more comparative reviews I'm reading the more I'm concluding that the A45 would be the far better car if you could constantly drive it like you stole it. The M135i would be better all the rest of the time. I think I'm showing my age by thinking that makes the BMW better for me.
I agree. And at our age we are at high risk of slipping a disk every time you get out if the AMG and then quickly lunge back in to grab the satnav you've left on the dash. biggrin
Virtually every review has mentioned the awful ride. I'm not sure I can have another car like that even if it's the best hatch in the road.

12TS

1,870 posts

211 months

Thursday 15th August 2013
quotequote all
Johnnytheboy said:
The more comparative reviews I'm reading the more I'm concluding that the A45 would be the far better car if you could constantly drive it like you stole it. The M135i would be better all the rest of the time. I think I'm showing my age by thinking that makes the BMW better for me.
Yup. Even if you could drive it thus, you'd loose your licence pronto.

Snowy roads may be a tester though smile

Kawasicki

13,100 posts

236 months

Thursday 15th August 2013
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anonymous said:
[redacted]
I think that the X/10ths description doesn't differentiate between road and track, it is a measure of the capability of the vehicle. Even in the top level of rallying you do not aim to drive at 10/10ths. Circuit driving you can aim for it, but even then it is risky. I would say 99% of enthusiastic drivers drive between 2 and 6/10ths. It is not embarrassing to say that you drive at 5/10ths on the public roads, that is pretty fast in a modern car, and might get some attention from the law.


DonkeyApple

55,570 posts

170 months

Thursday 15th August 2013
quotequote all
anonymous said:
[redacted]
There should be an industry standard table that reflects and grades the meaning of each tenth from both the perspective of the vehicle and a set for the driver. smile

Kronstein

294 posts

130 months

Friday 16th August 2013
quotequote all
Slightly disappointed by the AMG's 5.2/11.5 0-60 and 100 stats in this week's Autocar.

Room for a Black Series...

loudlashadjuster

5,159 posts

185 months

Friday 16th August 2013
quotequote all
Kronstein said:
Slightly disappointed by the AMG's 5.2/11.5 0-60 and 100 stats in this week's Autocar.

Room for a Black Series...
20 years ago these were Ferrari 348 numbers.

How far we've come...and we still moan! wink

DonkeyApple

55,570 posts

170 months

Friday 16th August 2013
quotequote all
loudlashadjuster said:
20 years ago these were Ferrari 348 numbers.

How far we've come...and we still moan! wink
They still are today. biggrin

Kronstein

294 posts

130 months

Wednesday 28th August 2013
quotequote all
loudlashadjuster said:
Kronstein said:
Slightly disappointed by the AMG's 5.2/11.5 0-60 and 100 stats in this week's Autocar.

Room for a Black Series...
20 years ago these were Ferrari 348 numbers.

How far we've come...and we still moan! wink
Since the test Autocar worked out, prompted by critisism no doubt, that the car has launch control. Retested as mentioned in today's issue with a 4.2 to 60 time. smile

I still vote for a Black series...

Wolands Advocate

2,495 posts

217 months

Wednesday 28th August 2013
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What plonkers!

I still recall that Top Gear got an RS3 to 60 in a faintly unbelievable 3.8 seconds.