Reducing torque for smoother city-cruising

[carl0s]

Hi.
Regarding my LS2/T56 from a 2005 GTO,

Is there any way of somehow making the engine feel less like a 2v/cyl 6.0 liter V8, and more erm, well less torquey at low throttle input? So more like a modern multi-valve DOHC engine (i.e. little torque at low rpm)?
When cruising in my LS2 RX7, it's kind of a fine balancing act with the throttle to avoid jerkiness. I just wonder if there's any kind of exponential available on the throttle input, or some engine torque reduction, or some other clever way of improving the car's manners at low speed city driving (>1,800 rpm, low speed, light throttle).

If the answer is "don't be stupid. It's a 6L pushrod V8", then fair enough, but I figure it's always worthwhile asking. My car is a daily driver, so noises, roughness, and bad manners are something that I'm slowly trying to iron out.

cheers,
Carl

[gmh308]

Hi.
Regarding my LS2/T56 from a 2005 GTO,

Is there any way of somehow making the engine feel less like a 2v/cyl 6.0 liter V8, and more erm, well less torquey at low throttle input? So more like a modern multi-valve DOHC engine (i.e. little torque at low rpm)?
When cruising in my LS2 RX7, it's kind of a fine balancing act with the throttle to avoid jerkiness. I just wonder if there's any kind of exponential available on the throttle input, or some engine torque reduction, or some other clever way of improving the car's manners at low speed city driving (>1,800 rpm, low speed, light throttle).

If the answer is "don't be stupid. It's a 6L pushrod V8", then fair enough, but I figure it's always worthwhile asking. My car is a daily driver, so noises, roughness, and bad manners are something that I'm slowly trying to iron out.

cheers,
Carl

You could try both...reducing torque B2514 and reducing throttle open rate...B2804, but looks like B2804 is not in there for E40's... :(

[swingtan]

It really depends on the exact reason for the current issue. The car shouldn't feel jerky, so it may be that some parts of the tune are not working right. What are the exact issues you are trying ti iron out? Do you have any log files that show the problem ?

Simon.

[gmh308]

It really depends on the exact reason for the current issue. The car shouldn't feel jerky, so it may be that some parts of the tune are not working right. What are the exact issues you are trying ti iron out? Do you have any log files that show the problem ?

Simon.

Actually light cars with large engines and light throttles this is a pretty normal PITA. Even for normal production cars. BMW E46 M3 was great at it. Just gotta take the foot off the pedal and start again. :)

But if the E40 had a table that reduced throttle sensitivity down low like they do with 4X4 trucks in low range, this would certainly help to "tune" it out. GM dulls the Corvette throttle substantially at low pedal angles to stop this 1500kg car buck jumping.

Edit - might have an answer for you. PM me if you want me to take a look at your tune and dull the throttle down.

[swingtan]

yes, I know what you mean about light cars......

The usual issues I've seen with "jerkiness" though ( talking tuned Gen IV ) are...


bucking at light throttle, low speed, low load. Usually between 1200 and 1600 with a steady throttle.
sudden "jump to life" when off throttle and then very light throttle is applied.
rough gear changes in a manual.
harsh exit from DFCO when cruising.


all of these are usually a pointer to the fueling being off, hence why I'd like to see some log data. Otherwise, just go with gmh308's offer via PM, I think he may have a trick or two up his sleeve.

Simon