From what I gather the Twinair has significantly reduced engine drag compared to any of the four cylinder engines. I suppose that’s generally a good thing as reduced friction improves mileage. However, can engine braking still be used effectively when going down a long and steep incline? I’m thinking of alpine passes like the Stelvio. I suppose using the brakes all the way down wouldn’t really be an option.
Technical Twinair engine braking
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Technical Twinair engine braking
ahmett
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Maybe, given that the TA has such rubbish engine braking, a parachute deployed at the back would be an option?
Maybe also carbon discs or at least some Ventilated Discs would provide better intense braking, because lord knows, the TA's brakes are not so good from what I experienced!
Good for driving in Knightsbridge at 30 mph, not so good for Stelvioing.
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Once, just for the hell of it, I tried freewheeling down the Bealach-na-Ba in a van. I made it about 1/3 of the way before frying the front brakes & spent a very pleasant hour or so admiring the scenery whilst waiting for it to cool down.
Most cars can't even make it down Porlock hill without some assistance from engine braking (the smell in the car park at Porlock on a summer's day is quite distinctive), so I'd share your concerns about the Stelvio.
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I don't find the engine braking a problem in my TA, and have driven on some quite hilly terrain.
And I don't find the TA's brakes problematic either; they're bigger than the 1.2's, after all.
I refer back to ahmett standard response that the TA is rubbish. It's not the car for you, we get that, but it's far from rubbish. And not all of us want to redline their car in every gear, all of the time.
Accepting that a FIAT 500 is not a high performance sports car (or even a medium performance sports car) is generally a good start. If I want to drive at ten tenths up and down Stelvio, I wouldn't take my 500.
And I don't find the TA's brakes problematic either; they're bigger than the 1.2's, after all.
I refer back to ahmett standard response that the TA is rubbish. It's not the car for you, we get that, but it's far from rubbish. And not all of us want to redline their car in every gear, all of the time.
Accepting that a FIAT 500 is not a high performance sports car (or even a medium performance sports car) is generally a good start. If I want to drive at ten tenths up and down Stelvio, I wouldn't take my 500.
Just stick it in a lower gear, you'll then get better engine breaking, often have to use 2nd in my car, keeps it to around 25-30 on steep down hill sections. 
...often have to use 2nd in my car, keeps it to around 25-30 on steep down hill sections.
The mountain passes of East Anglia must be formidable indeed!
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The mountain passes of East Anglia must be formidable indeed!
Doing over 20k a year I do regularly leave the 'supposed' flat lands of EA. You ever been to Norwich out of interest?
Was up that way for a few days this time last year. I particularly enjoyed the snowdrop walk at Oxburgh Hall, and a pleasant ride on the Bure Valley Railway
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Ah, Greenmount hill. My 504 once blew its brake booster up in the hills, obviously to get home I'd have had to go down greenmount hill with virtually no brakes which wasn't a good idea. A call to my dad and a brake booster assembly was brought out and the car was repaired in about 10 minutes by the roadside
TA brakes are just fine Ahmett, in fact they are over eager for being on or off, I have done Stelvios pass on them and quite a few other mountains in 2011. Only Mont Blanc this year (in the TA)
Btw Knightsbridge is 20mph as you have to slow down and admire the window displays.
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TA brakes are just fine Ahmett, in fact they are over eager for being on or off, I have done Stelvios pass on them and quite a few other mountains in 2011. Only Mont Blanc this year (in the TA)
Btw Knightsbridge is 20mph as you have to slow down and admire the window displays.
Further to this, I'd like to clear up a few points for Ahmett's benefit.
The brake master cylinder diameter of the TA is 7/8" - which is just the same as the 1.4 (but different to the 1.2 - at 13/16")
The brake servo diameter is exactly the same as the 1.4.
The brake disc size of the TA is 257mm - the same size as the 1.4 (albeit not ventilated, but this won't make a jot of difference for anything other than repeated hard braking followed by higher speed runs to cool the brakes (not really going to help on a mountain pass).
The caliper piston size of the TA is 54mm, the same size as the 1.4 (and bigger than the 1.2).
The only difference is the rear brakes are drum, rather than disc - but the total swept area of friction surface of a drum brake is actually larger, the only reason discs replace drums is for cooling purposes. Being rear brakes, and only contributing to around 10-15% of braking effort in normal circumstances means their size is academic.
So what does this tell us? The brakes will feel the same as a 1.4, i.e. the pedal pressure you have to exert to achieve a certain line pressure, and then the pressure exerted on the pad will be exactly the same. So, if the friction material is the same (which it is from factory fit), the brake torque is the same, so the retardation force is the same.
The ONLY variable that's different is that the TA has a vacuum pump providing vacuum for the brake servo, as opposed to inlet manifold vacuum supply for the 1.4. This actually means that, generally, the vacuum level for the servo is higher as the vac pump is always running, whatever the throttle opening is. With an inlet vacuum supplied servo, a vacuum is only generated when the throttle is shut (and by all accounts, that's not very often, given the way you drive!)
So, I suspect you've driven only one TA, and the brakes were probably new, the pads weren't 'cured' (as is the case with brand new ones), and you drove it like you stole it, overheated the brakes and had them fade. I haven't driven a 1.4, that's true, but I find the braking perfectly adequate for normal road usage on my car - and it appears others have too.
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Smaller brake master cylinder on the 1.2 and different sized caliper piston giving a hydraulic leverage ratio of approx. 2.3259 vs 2.4297 on the TA.
I suspect the 1.2 then has a more powerful servo to assist the fact you have a more direct relationship between the pedal and the caliper (i.e. you press the pedal less to move the caliper piston the same amount - which means you have to press it 'harder' to exert the same pressure on the pad). This'll make the brakes feel different.
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I wonder, are the rear drums lighter than discs would be? Marelli make a set of finned drums that would just finish off the retro look IMO. I always thought finned drums were cool
Could be - the caliper is a fair old lump. Need drums like the old 'Minifins' that you could get for the Mini, which were a nice lightweight aluminium with a steel liner shrink fitted inside. As you say, very cool
The Twins
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Thanks for the explanation bgunn ; )
The Twins
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Could be - the caliper is a fair old lump. Need drums like the old 'Minifins' that you could get for the Mini, which were a nice lightweight aluminium with a steel liner shrink fitted inside. As you say, very cool
I want some of them 'finned' drums : P
You say Marelli do them for the 500 TA UFI?
Only on a boat, lol ... and with no locks to negotiate it was lovely and flat, lol.
