Increasing torque at lower rpms

rdkarthik · 1st May 2007, 22:14

Quote:

Originally Posted by theMAG

Another unique thing that will work: get a remapped ECU to fire all injectors simultaneously rather than sequentially - as in stock. You'll NOTICE a difference. But the mileage will drop atleast 35%.

Impossible. Mileage does not drop 35% in batch when compared to sequential... Performance does not increase either.. Wonder where you got that info from.

A programmable/remapped ECU with custom/modified fuel and ignition curves can increase the low end grunt ...

sbasak · 1st May 2007, 22:39

Usually for each Liter of engine size (petrol) max torque can be produced is 100 Nm
It depends on lots of factors including engine's volumetric efficiency (mainly).
It is easy to increase BHP of engine with some aftermarket apparatus but difficult to increase torque because of the inherent design of how engines work.
If you want high torque at low RPM, simply use a diesel engine (or go for the highest engine size you can afford) or electric motor (full torque at any RPM).
The design of diesel engine is such that it produces high torque (since it uses very high compression).

aZa · 1st May 2007, 22:42

Mileage is affected because one tends to rev the car more due to the throaty sound produced by the FFE. But you can tune the FFE system to be silent. If one drives the car normally then the mileage should actually increase.

theMAG · 1st May 2007, 23:31

Quote:

Originally Posted by rdkarthik

Impossible. Mileage does not drop 35% in batch when compared to sequential... Performance does not increase either.. Wonder where you got that info from.

From a Bangalore customer. We could take this offline if you'd like. I'd urge anyone not to take a defensive stance since its not my objective in life to comment unneccesarily about anything.

Quote:

Originally Posted by rdkarthik

A programmable/remapped ECU with custom/modified fuel and ignition curves can increase the low end grunt ...

I know - and the reason I put it up as a solution. Its a fantastic solution - I've driven a car with the afore-mentioned ECU

theMAG · 1st May 2007, 23:45

Quote:

Originally Posted by mclaren1885

True .. I think he got confused by SC .. Unlike TC's they dont have lag ..

Yup - my mistake. I meant SCs - and a sufficiently capable engine to churn the SC

rdkarthik · 2nd May 2007, 09:58

Quote:

Originally Posted by theMAG

From a Bangalore customer. We could take this offline if you'd like. I'd urge anyone not to take a defensive stance since its not my objective in life to comment unneccesarily about anything.

I know - and the reason I put it up as a solution. Its a fantastic solution - I've driven a car with the afore-mentioned ECU

Increase in performance or drop in FE (35%) has nothing to do with injection firing pattern.. Dosent matter whether you go batched , semi or full sequential..

Engine performance and FE are governed by fuel and ignition curves.. For the same curves, all types of injector firing patterns will produce identical figures for performance and FE (+/- 2 to 3%) .. Hope you get the concept..

Nothing defensive here dude, have no clue who you are talking about, either way nice to know you like it

... The car you talk about probably needs work on cruise and part throttle region of the fuel maps..

TURBOSAM · 2nd May 2007, 13:10

the ex pipes are not twisted ,
the 4-2-1 or 4-2 exhaust system will definately imprve the performance ...only it is well designed and well execuated
,

theMAG · 2nd May 2007, 14:45

Quote:

Originally Posted by rdkarthik

Nothing defensive here dude, have no clue who you are talking about, either way nice to know you like it

...

Karthik,

The afore-mentioned car's mileage drops to 9-10 kmpl while in batch mode, compared to 15 while on sequential firing; according to the owner - who's a very experienced driver. But - as you mentioned, I love that tuned ECU and the way power kicks in due to the batch mode - I wouldnt be surprised if I decide to get it for my Swift shortly.

mclaren1885 · 2nd May 2007, 15:05

Quote:

Originally Posted by theMAG

The afore-mentioned car's mileage drops to 9-10 kmpl while in batch mode, compared to 15 while on sequential firing; according to the owner - who's a very experienced driver.

I hope you are considering the nature of driving as well .. Any mod to the engine will only make your right foot heavy all the time (to reap the max out of what you spent) owing to the low FE .. And I am talking from personal experience .. Also any other mods on the car ??

theMAG · 2nd May 2007, 15:22

Quote:

Originally Posted by mclaren1885

I hope you are considering the nature of driving as well .. Any mod to the engine will only make your right foot heavy all the time (to reap the max out of what you spent) owing to the low FE ..

I know

Quote:

Originally Posted by mclaren1885

And I am talking from personal experience ..

I know I know

Quote:

Originally Posted by mclaren1885

Also any other mods on the car ??

Oooh - wouldnt you like to know ?!

mclaren1885 · 2nd May 2007, 15:33

Quote:

Originally Posted by theMAG

Oooh - would you like to know ?!

YES !! Maybe that will enable us to make a detailed analysis for the 35% drop in FE as you mentioned ..

theMAG · 2nd May 2007, 15:37

Quote:

Originally Posted by mclaren1885

YES !! Maybe that will enable us to make a detailed analysis for the 35% drop in FE as you mentioned ..

Right. For the benefit of all mankind who wish to increase their low end torque, I shall take upon this with utmost responsiiblity myself - you'll be posted with the results.

swathyd · 2nd May 2007, 16:48

what about porting and polishing ? Is it easier than say ffe ?

rdkarthik · 2nd May 2007, 21:35

Quote:

Originally Posted by theMAG

Karthik,

The afore-mentioned car's mileage drops to 9-10 kmpl while in batch mode, compared to 15 while on sequential firing; according to the owner - who's a very experienced driver. But - as you mentioned, I love that tuned ECU and the way power kicks in due to the batch mode - I wouldnt be surprised if I decide to get it for my Swift shortly.

Before you confuse yourself, the performance gains or FE is NOT due to batch firing mode... It will behave the same in semi-sequential or sequential (here i go again

).... No matter who is diving, the changes are due to different fuel and ignition maps.....

swathyd · 2nd May 2007, 23:37

Please come back to topic rather than debating over ecu tweaking.

1st May 2007, 22:39	#17
sbasak BHPian Join Date: Nov 2005 Location: CCU-LTN Posts: 608 Thanked: 14 Times	Usually for each Liter of engine size (petrol) max torque can be produced is 100 Nm It depends on lots of factors including engine's volumetric efficiency (mainly). It is easy to increase BHP of engine with some aftermarket apparatus but difficult to increase torque because of the inherent design of how engines work. If you want high torque at low RPM, simply use a diesel engine (or go for the highest engine size you can afford) or electric motor (full torque at any RPM). The design of diesel engine is such that it produces high torque (since it uses very high compression). Last edited by sbasak : 1st May 2007 at 22:45.
	() Thanks

1st May 2007, 22:42	#18
aZa Senior - BHPian Join Date: Mar 2006 Location: Noida / Delhi Posts: 1,595 Thanked: 21 Times View My Garage	Mileage is affected because one tends to rev the car more due to the throaty sound produced by the FFE. But you can tune the FFE system to be silent. If one drives the car normally then the mileage should actually increase.
	() Thanks

2nd May 2007, 13:10	#22
TURBOSAM BHPian Join Date: Jul 2006 Location: pune Posts: 241 Thanked: 2 Times	hi the ex pipes are not twisted , the 4-2-1 or 4-2 exhaust system will definately imprve the performance ...only it is well designed and well execuated ,
	() Thanks

2nd May 2007, 16:48	#28
swathyd BHPian Join Date: Mar 2007 Location: thiruvananthapuram Posts: 774 Thanked: 25 Times	what about porting and polishing ? Is it easier than say ffe ?
	() Thanks

2nd May 2007, 23:37	#30
swathyd BHPian Join Date: Mar 2007 Location: thiruvananthapuram Posts: 774 Thanked: 25 Times	Please come back to topic rather than debating over ecu tweaking.
	() Thanks