Will torque increase in line with BHP?

NC10

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Hi all,

I have a A5 2.0tfsi convertible soon to have a hybrid turbo on it. The turbo is good for up to 350 bhp, depending on other mods. For the sake of this question just think I have 350.

Standard power is 208 which means I'll have a 68% increasein bhp, will torque increase at the same rate? So the standard 258lbs/ft would become 433??

Also how about acceleration? Below is specs for the S5 and RS5 convertible, where do you think I'd fit in? Standard 0-60 for mine is 7.5. I'd have more power than the S5 and probably more torque. I'll have less power than the RS5 but more torque.

S5 convertible:
0-60 5.6
328 bhp
324 lbs/ft

RS5 convertible:
0-60 4.6
444 bhp
317 lbs/ft

I'll post the actual figures once all the work has been done but what you reckon?

Cheers
 
Torque and power are directly related. (RPM x Torque) / 5252 = power .
If the power increased by 68% then the torque would increase by 68% . But in your case the peak power and peak torque readings you have are not at the same RPM.
Peak torque looks to be around 3700 rpm where as peak power is more like 5500 RPM.
There is a calculator here that will give you BHP for a given torque value at a certain RPM.
https://spicerparts.com/calculators/horsepower-torque-calculator .
The hybrid turbo allows the engine to hold the torque to higher RPM's so if you could hold 320Lb/ft to 6500 rpm you would be making 396bhp.
That's why the RS5 makes a lot more power than the S5 but less torque. The peak power and peak torque on an RS5 are at much higher RPM''s. I would suspect the peak torque on a 350 bhp map would be around 320-330Lb/ft. Performance would be similar to an S5 I would say.

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Thanks for the detailed reply, appreciated.

Yeah I forgot peak torque/bhp were at a different rpm. So the RS5 has lower torque but can hold on to it longer equals more bhp.

I'd be happy with S5 performance, but with a litres worth of engine missing, I'm thinking I could maybe just nick it.

Yeah it's quattro with S-Tronic.
 
Thanks for the detailed reply, appreciated.

Yeah I forgot peak torque/bhp were at a different rpm. So the RS5 has lower torque but can hold on to it longer equals more bhp.

I'd be happy with S5 performance, but with a litres worth of engine missing, I'm thinking I could maybe just nick it.

Yeah it's quattro with S-Tronic.
Real world numbers on the S4/S5 engine regularly seem to exceed the numbers Audi quote by a good margin. Standard power and torque are more like 350 bhp 350Lb/ft . You aren't dragging quite as much weight around though as an S5 cab though.
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