Low end torque
10-02-2016, 10:33 AM
#1
Low end torque
the low end torque (say from rev 1500 to 2200) of my 2004 turbo is a little bit mild than what I have expected.
The factory figure is about 415 lb ft at 2700 rev which is quite a great deal of power even in nowaday standard
not yet really tested as i am busy in cleaning my new ride
May be the first thing to do is to add techron to clean the injectors and the second things to do are to change spark plugs /an afe air filter.....(not mobile 1 as the seller has changed it recently)
https://www.caltex.com/hk/zh/motorists/products-and-services/techron-concentrate-plus.html
The factory figure is about 415 lb ft at 2700 rev which is quite a great deal of power even in nowaday standard
not yet really tested as i am busy in cleaning my new ride
May be the first thing to do is to add techron to clean the injectors and the second things to do are to change spark plugs /an afe air filter.....(not mobile 1 as the seller has changed it recently)
https://www.caltex.com/hk/zh/motorists/products-and-services/techron-concentrate-plus.html
10-02-2016, 10:48 AM
#2
a tune will transform the car
10-02-2016, 11:09 AM
#3
Three Wheelin'
the understatement of the year...
I don't think I'm ever wanting for more low end on the street with my Cobb tune (let alone the 100 octane Sambo special I'm presently running), it's hard enough to maintain traction in 1st and 2nd gear as it is...
I don't think I'm ever wanting for more low end on the street with my Cobb tune (let alone the 100 octane Sambo special I'm presently running), it's hard enough to maintain traction in 1st and 2nd gear as it is...
10-02-2016, 12:25 PM
#5
Better now after using Vpower of shell + techron additive of Caltex
i think the previous user had never used any fuel system cleaner and he only bought low octane fuel for the last tank before transaction😄😄
i think the previous user had never used any fuel system cleaner and he only bought low octane fuel for the last tank before transaction😄😄
10-02-2016, 12:34 PM
#6
Still one down side in comparing with my highly modified 2013?bmw 5 series basic model:
the car slow down quite fast when i release my right foot
(i have used afe dry type intake & gfb DV in my bmw - it runs for quite a while without the need to give fuel after the above modification. Very leisure feel and this save fuel too )
Any suggestions for the corresponding mod for turbo? Thx
the car slow down quite fast when i release my right foot
(i have used afe dry type intake & gfb DV in my bmw - it runs for quite a while without the need to give fuel after the above modification. Very leisure feel and this save fuel too )
Any suggestions for the corresponding mod for turbo? Thx
Last edited by fung0001; 10-02-2016 at 12:50 PM.
10-02-2016, 12:37 PM
#7
Three Wheelin'
Good to hear. K16s make good bottom end and midrange...esp when well tuned.
Trending Topics
10-02-2016, 09:50 PM
#9
My low end torque sucks... boost doesn't come on until around 3500-3700 rpms. (GT700 kit)
upgrade like high flow intake , down pipe & exhaust pipes will increase hp & torque in mid range and upper end
but will have significant impact on torque at the low end.....
10-02-2016, 11:20 PM
#10
Can you run without cats over there? Turbo cars want the least back pressure possible. A nice free flowing exhaust will set more power free!! 
If you decide to do a tune the tuner can also work with you and optimize the tune to your liking.
If you decide to do a tune the tuner can also work with you and optimize the tune to your liking.
10-03-2016, 02:00 AM
#11
Thx
I learnt from the webpage of stone (taiwan exhaust company) that reduce in restriction of exhaust system （and therefore less back pressure）will improve mid to higher end performance in the expense of low end torque. That's why stone produce the so called "spiral" designed dp to enable improvement in all low mid high ends for 5 series.
I learnt from the webpage of stone (taiwan exhaust company) that reduce in restriction of exhaust system （and therefore less back pressure）will improve mid to higher end performance in the expense of low end torque. That's why stone produce the so called "spiral" designed dp to enable improvement in all low mid high ends for 5 series.
Last edited by fung0001; 10-03-2016 at 06:33 AM.
10-03-2016, 09:42 AM
#12
Pro
but for low end torque, back-pressure actually helps... up until ~3k+ RPM The back-pressure 'assists' in spool-up. This is from my experience, not yet with a 996 Turbo, but shouldn't be different unless you have a variable vane turbo.
10-03-2016, 01:59 PM
#14
Three Wheelin'
Back pressure causes a slow down in exhaust flow at the point of the bottleneck and this pressure builds up in the exhaust pipe and into the turbine housing; to overcome this restriction will take more energy to spin the turbine wheel.. Less restrictions, less energy required to spin the turbine wheel, turbo builds boost faster, makes more torque/power at a lower rpm.
10-03-2016, 03:08 PM
#15
Three Wheelin'
No, it really doesn't. This is not the case in any turbocharged vehicle.
Back pressure causes a slow down in exhaust flow at the point of the bottleneck and this pressure builds up in the exhaust pipe and into the turbine housing; to overcome this restriction will take more energy to spin the turbine wheel.. Less restrictions, less energy required to spin the turbine wheel, turbo builds boost faster, makes more torque/power at a lower rpm.
Back pressure causes a slow down in exhaust flow at the point of the bottleneck and this pressure builds up in the exhaust pipe and into the turbine housing; to overcome this restriction will take more energy to spin the turbine wheel.. Less restrictions, less energy required to spin the turbine wheel, turbo builds boost faster, makes more torque/power at a lower rpm.