What N/A Petrol with Turbodiesel-like characteristics?
Discussion
I need the help of the PH massive to answer a long-time curiosity of mine, but have no resources to do it on my own. 
To set some context, I have never driven a petrol car (I'm a young/newish driver), so seeing the various threads that pop up time and and again in here, I'm curious to know what the benefits of an N/A petrol would be like.
I drive a early 90s Citroen D-Turbo (1.9). I like the turbo and the power delivery when on-boost i.e. from ~2.5k to ~4k rpm. I understand that a petrol engine is a lot less 'peaky' and the power is maintained a lot longer than 4K, typically about 6k before dropping off. Many many times when I'm out driving, I have wondered if a petrol car exists that would maintain the peak power and torque that my TD produces to up about 6k revs. That would be very useful and more enjoyable, I'd have thought.
So, the aim of the thread is to find an N/A petrol that can produce the peak power/torque that my diesel produces at a similar rev point, but maintain it much longer than the diesel, preferably to about 6k revs. I'm interested to see what capacity would the N/A petrol have to be to achieve such a statistic and what end point power and torque the N/A would produce in order to achieve the same accelerative feeling I get when my turbodiesel is on-boost, but for much longer in the petrol, of course!
Feel free to choose another car if the 1.9 TD is too hard to answer! I imagine we'd need the dyno curves of the turbodiesel and the N/A petrol to judge correctly. I don't have any of those and I'm sure someone much brighter than I is in here, who can shed light on this conundrum!
An easier one should be the all-conquering 335d (stock!). So if my 1.9 TD is hard to answer, what about the 335d? What N/A petrol car can give the same acceleration of the 335d, producing the same peak power/torque at the same rev point as the 335d but maintain it longer, as apparently a Petrol should do?
To set some context, I have never driven a petrol car (I'm a young/newish driver), so seeing the various threads that pop up time and and again in here, I'm curious to know what the benefits of an N/A petrol would be like.
I drive a early 90s Citroen D-Turbo (1.9). I like the turbo and the power delivery when on-boost i.e. from ~2.5k to ~4k rpm. I understand that a petrol engine is a lot less 'peaky' and the power is maintained a lot longer than 4K, typically about 6k before dropping off. Many many times when I'm out driving, I have wondered if a petrol car exists that would maintain the peak power and torque that my TD produces to up about 6k revs. That would be very useful and more enjoyable, I'd have thought.
So, the aim of the thread is to find an N/A petrol that can produce the peak power/torque that my diesel produces at a similar rev point, but maintain it much longer than the diesel, preferably to about 6k revs. I'm interested to see what capacity would the N/A petrol have to be to achieve such a statistic and what end point power and torque the N/A would produce in order to achieve the same accelerative feeling I get when my turbodiesel is on-boost, but for much longer in the petrol, of course!
Feel free to choose another car if the 1.9 TD is too hard to answer! I imagine we'd need the dyno curves of the turbodiesel and the N/A petrol to judge correctly. I don't have any of those and I'm sure someone much brighter than I is in here, who can shed light on this conundrum!
An easier one should be the all-conquering 335d (stock!). So if my 1.9 TD is hard to answer, what about the 335d? What N/A petrol car can give the same acceleration of the 335d, producing the same peak power/torque at the same rev point as the 335d but maintain it longer, as apparently a Petrol should do?
This is why I chose turbo diesel. I can fill it with people and gear, then hitch a one tonne trailer to the back, and it'll cruise very quietly at 0.80 leptons in top gear smack bang in the middle of the torque band. It's a two litre and all the while does 30mpg. I think I'd need and engine three times the size to have that useful torque and response to hand.
That is astonishing.
According to Parkers, my TD is supposed to have 90bhp and 148 lb/ft peak stats. I don't know where in the rev range it is being produced. But lets say, at 3500 rpm. What would be the peak power of an N/A petrol that can maintain this power/torque to 6000 rpm? How does one calculate this? Then we can probably get an idea of what capacity the N/A Petrol has to be by comparing with existing cars.
Anyone help?
According to Parkers, my TD is supposed to have 90bhp and 148 lb/ft peak stats. I don't know where in the rev range it is being produced. But lets say, at 3500 rpm. What would be the peak power of an N/A petrol that can maintain this power/torque to 6000 rpm? How does one calculate this? Then we can probably get an idea of what capacity the N/A Petrol has to be by comparing with existing cars.
Anyone help?
All that jazz said:
You won't get it with a NA car because the thing that gives you the punch you get in your coal burner from 2.5-4k is the blower. If you want the same punch with a petrol then you'll need one with a blower as well.
Okay. I like that idea as I like turbos! What Turbo-petrol can do what my diesel does at the same rev-point but much longer?Dr Z said:
That is astonishing.
According to Parkers, my TD is supposed to have 90bhp and 148 lb/ft peak stats. I don't know where in the rev range it is being produced. But lets say, at 3500 rpm. What would be the peak power of an N/A petrol that can maintain this power/torque to 6000 rpm? How does one calculate this? Then we can probably get an idea of what capacity the N/A Petrol has to be by comparing with existing cars.
Anyone help?
IIRC, 148lb/ft is the exact torque figure of a Clio 172. According to Parkers, my TD is supposed to have 90bhp and 148 lb/ft peak stats. I don't know where in the rev range it is being produced. But lets say, at 3500 rpm. What would be the peak power of an N/A petrol that can maintain this power/torque to 6000 rpm? How does one calculate this? Then we can probably get an idea of what capacity the N/A Petrol has to be by comparing with existing cars.
Anyone help?
The fact that a diesel will produce it's torque in a narrower band is what makes it 'feel' powerful, if you see what I mean.
Dr Z said:
That is astonishing.
According to Parkers, my TD is supposed to have 90bhp and 148 lb/ft peak stats. I don't know where in the rev range it is being produced. But lets say, at 3500 rpm. What would be the peak power of an N/A petrol that can maintain this power/torque to 6000 rpm? How does one calculate this? Then we can probably get an idea of what capacity the N/A Petrol has to be by comparing with existing cars.
Anyone help?
Do you mean he peak power of a n/a petrol that can maintain at least 90bhp from say 3500rpm to 6000rpm.According to Parkers, my TD is supposed to have 90bhp and 148 lb/ft peak stats. I don't know where in the rev range it is being produced. But lets say, at 3500 rpm. What would be the peak power of an N/A petrol that can maintain this power/torque to 6000 rpm? How does one calculate this? Then we can probably get an idea of what capacity the N/A Petrol has to be by comparing with existing cars.
Anyone help?
Dr Z said:
Okay. I like that idea as I like turbos! What Turbo-petrol can do what my diesel does at the same rev-point but much longer?
I suspect there is a 1.4 turbo out there that can manage that, the power at 6000rpm would be much higher than 90bhp. You could probably fit a boost controller and program it to reduce the boost at higher rpms to restrict it to 90bhp if you really wanted to.Toltec said:
Dr Z said:
Okay. I like that idea as I like turbos! What Turbo-petrol can do what my diesel does at the same rev-point but much longer?
I suspect there is a 1.4 turbo out there that can manage that, the power at 6000rpm would be much higher than 90bhp. You could probably fit a boost controller and program it to reduce the boost at higher rpms to restrict it to 90bhp if you really wanted to.Toltec said:
Ah! That's great. Pretty much what I asked originally. But, there is a twist in the tail that hadn't occurred to me when I posed the original question. 
My Citroen weighs approx 1100 kg. How much does that Golf weigh? It is unlikely that the Golf will give a similar feeling of acceleration even though the engine produces the power/torque that I require, as I doubt it weighs the same as my car, what with it being modern and all. Any ideas of how this can be solved?I ask this because it is a shame that you have to go to a large capacity V8 to get what amounts to an extended version of a primitive diesel. That is very surprising, considering how much TDIs or indeed anybody who drives a diesel is derided on here. N/A Petrol being the zenith of petrolheadedness, with lots of PHers lauding the throttle-response of an N/A Petrol. In order for me to experience the famed "throttle-response" without feeling like I'm going backwards (!) when I put my foot down...I'll never be able to afford a uber-CC V8 and therefore be never able to experience the alleged purity of petrolheadness.
Dr Z said:
Okay. I like that idea as I like turbos! What Turbo-petrol can do what my diesel does at the same rev-point but much longer?
My turbo petrol hits 360lb/ft at 3100rpm. Drops to 300lb/ft at 5300rpm270bhp+ between 4200rpm-6300rpm.
That's from a 2.5 Impreza. It can even manage 300 miles to a tank.
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