It’s a question that’s always puzzled me...
On here, I wrote...
"Paul, I understand how 204bhp at 0.92bar is quite a bit quicker than 165bhp at 0.65bar but I assume another car of the same weight with 204bhp at 0.65bar would be equally quick. Likewise 204bhp and no turbo.
John, I was hoping for a short cut to my understanding – I might have to do some reading.
David, “overtaking safely in about half the normal distance” This is where I get confused… increasing the boost from 0.65 to 0.92 dramatically improves the acceleration…
My car is like a four wheeled motorbike, it accelerates like mad.
Remember it’s my first turbo… and I haven’t driven it flat out in terms of speed or acceleration.
When I drove it home on the first day I was surprised the boost gauge never moved, and it didn’t move for the first fortnight. Only accelerating quickly brought it into action, and it’s still the same.
I imagine you could steadily accelerate up to 130mph without the boost gauge moving. I imagine you could rev the engine steadily up to 7000 revs and it wouldn’t move?
The boost seems to be directly related to the speed of the throttle opening rather than the amount it is opened. If this is the case presumably to halve the acceleration time when overtaking you would need to floor the pedal and wait for the results. I tend to squeeze the throttle down in keeping with the response from the engine rather than using it like a switch.
The bit I was trying to understand was this…because the turbo boost is gradual from 0 to 0.92 and seemingly related to the speed of the throttle opening, at what point do you see the extra performance supplied by the 0.65 to 0.92 element. Is it that when you floor the pedal on a standard car you get acceleration in keeping with 0.65bar and after uprating the pressure you get the further benefit of an extra 4lbs/in² - right from the start?
Does it only apply to flooring the pedal? I haven’t took particular notice but I imagined you could overtake a car quickly without even reaching the 0.65. Mine seems to still be making its way up when it’s time to slow down again.
Or is it just the gauge that is gradual, and the turbo is instantly 0.65 or 0.92?
I’m referring to driving on the road, in keeping with the original question.
Thanks Ray"