Is Torque Overrated ?

Fr0dders

Fr0dders

Fr0dders

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Reason i ask is that prior to getting my remap, i'd held the oppinion (as others seem to do) that the reason that Diesels accelerate quicker in gear, is due to the increased torque.

Now, the vectra vxr has gone from a dyno proven 300 ish lb/ft to 394 lb/ft

I would have thought a near 100 lb/ft torque increase would provide some sizeable gains in acceleration, rvr if only for in gear acceleration - diesel style.

Now ive been testing with dynolicious that is producing some very accurate 1/4 mile numbers (when looking at what others with similar setups are doing on proper timed drag strips) so i know the data is in the right sort of ballpark.

How much would you reckon the 30-70mph in gear acceleration time would be reduced by

and what difference in the 0-60 time ? the answers may surprise you.
 
Too many people think torque and power are 2 different things (not saying this is you, just too many people rave about torque as if petrols don't have it).

Any increase in torque across a portion of the rev-range is a good thing really.

But when it comes down to it, the be all and end all is power, so long as you have the correct gear to use it.
 
Depends what the remap has done to the torque curve.
Comparing standard to remap, where does the remap car show it's advantages and by what margin?
 
Very. Horse power is what matters. In fact it's the only thing that matters when combined with suitable gearing. I can easily produce over 400 lb/ft but I'd struggle to produce even 1 hp
 
before and after graphs

P1020282.jpg


Same dyno, same operator, same day, only a few hours apart. So regardless of the numbers, the increase is correct. Bottom graph is befpre/after torque.
 
There was a VERY useful letter in last months Evo magazine written by the head of engineering at Bosch Research I think it was about what torque means and why having loads of torque doesnt neccesarily mean having a fast car. I'm not going to type it all out but it made lots of sense and did things like compare the torque output of a 530d with that of an M5 (The 530d had more yet the M5 is massively faster).

This obsession with torque is a recent thing largely perpetated by the owners of diesel cars who, keen to convince the world they didn't compromise, cite huge torque output as some sort of superiority over more powerful petrol engines.
 
The whole thing with "torque" in diesels is, you can accelerate quicker on motorways without changing gear, which IMO is useful.
 
I think you're being slightly harsh on diesel drivers there. They do feel quicker at low rpm, simply because they tend to produce more power there (power = torque * rpm) which makes them good for lorries and vans :)
 
massive amounts of torque is good for one thing.... shredding tyres!

Only reason modern diesels feel quicker is due to most if not all current diesel cars having a turbo charger.

Stick a turbo charger in a petrol car and it will FLY!
 
Its all down to the engine and how its power is being used.

High torque is useful, because it allows the car to "pull" in almost anygear, I can do 6th gear at 30 mph and still accelerate perfectly fine in my ST.

Surely though if your going to compare a modern turbo charged diesel to a petrol car, shouldnt it be a turbo charged petrol ?
 
MrLOL said:
Reason i ask is that prior to getting my remap, i'd held the oppinion (as others seem to do) that the reason that Diesels accelerate quicker in gear, is due to the increased torque.

Now, the vectra vxr has gone from a dyno proven 300 ish lb/ft to 394 lb/ft

I would have thought a near 100 lb/ft torque increase would provide some sizeable gains in acceleration, rvr if only for in gear acceleration - diesel style.

Now ive been testing with dynolicious that is producing some very accurate 1/4 mile numbers (when looking at what others with similar setups are doing on proper timed drag strips) so i know the data is in the right sort of ballpark.

How much would you reckon the 30-70mph in gear acceleration time would be reduced by



and what difference in the 0-60 time ? the answers may surprise you.
Click to expand...

So come on then how much difference did it make :)
 
[TW]Fox;15190908 said:
There was a VERY useful letter in last months Evo magazine written by the head of engineering at Bosch Research I think it was about what torque means and why having loads of torque doesnt neccesarily mean having a fast car. I'm not going to type it all out but it made lots of sense and did things like compare the torque output of a 530d with that of an M5 (The 530d had more yet the M5 is massively faster).

This obsession with torque is a recent thing largely perpetated by the owners of diesel cars who, keen to convince the world they didn't compromise, cite huge torque output as some sort of superiority over more powerful petrol engines.
Click to expand...

I think that appeared in either the IMechE mag, PE or the Engineering & Technology mag that the IET do. It was a good article.

0-60 most people will be traction limited then rag to the redline in both 1st and 2nd so i wouldn't expect much difference in that based on that power curve. Might be even worse due to the extra torque making hooking the tyre up more difficult.

Is this a thread for that FAQ :p
 
MadMossy said:
Its all down to the engine and how its power is being used.

High torque is useful, because it allows the car to "pull" in almost anygear, I can do 6th gear at 30 mph and still accelerate perfectly fine in my ST.
Click to expand...

Thats high torque at low revs then? High torque but at high revs would have no effect on the situtation you have just described. The location of the peak is just as important as its magnitude.
 
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