Is peak torque/best economy at the same revs on 1/2 or 1/4 throttle?
You dont want to be flooring it down the motorway...not for economy anyway
Oh no...my rear end...its gay!
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Anonymous
Gearing UP
Hi Folks,
Now that is a good question?
I would suppose on a four barrel vac secondary, that would be just before the secondaries open, which is approx. 40percent throttle???
But thereagain a spreadbore may be different, much smaller primaries?
Whats the best anyones got out of a B/B?
My 383 Cuda was 17mpg on the freeway!!!
My 440 iron head racecar was less than one on the strip!!!
Baccy.
Now that is a good question?
I would suppose on a four barrel vac secondary, that would be just before the secondaries open, which is approx. 40percent throttle???
But thereagain a spreadbore may be different, much smaller primaries?
Whats the best anyones got out of a B/B?
My 383 Cuda was 17mpg on the freeway!!!
My 440 iron head racecar was less than one on the strip!!!
Baccy.
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Dave-R
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- Location: Dave Robson lives in Geordieland
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Makes no difference. It is when your engine is being as efficient as possible. Hence the fact it is making the most torque. On a hopped up street/strip engine this could be anywhere between 3000 and 5000rpm.Jon wrote:Best economy on full throttle is at peak torque
Is peak torque/best economy at the same revs on 1/2 or 1/4 throttle?
On my car it is about 4000-4500rpm. I get much better economy at 90mph than I do at 70.
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Anonymous
MPG
Hi Dave,
Thats well interesting.
We tend to build our cars for best mpg at around 70mph, mainly because we have speed cameras every 100metres down South.
I assume the speed limit must be different up North, or do you just not bother to pay the fines???
Only pullin ya leg!!! Most of these Sothern Softee mobiles won't do 90mph flat out?
Keep up the good work Baccy.
Thats well interesting.
We tend to build our cars for best mpg at around 70mph, mainly because we have speed cameras every 100metres down South.
I assume the speed limit must be different up North, or do you just not bother to pay the fines???
Only pullin ya leg!!! Most of these Sothern Softee mobiles won't do 90mph flat out?
Keep up the good work Baccy.
Last edited by Anonymous on Mon Nov 26, 07 7:45 pm, edited 1 time in total.
Speed doesn't seem to make much difference to my economy, 12mpg whatever I do...flat torque curve? 
I'm just not sure that'd work on a tall geared car, just because the engine is at its most efficient doesn't mean everything else is ideal(wind resitance etc), and if you're burbling along at 70 mph at just off idle and hardly any throttle like some of the yanks I've been in I cant see dropping to second to get it up to peak torque as being the best economy tip
I'm just not sure that'd work on a tall geared car, just because the engine is at its most efficient doesn't mean everything else is ideal(wind resitance etc), and if you're burbling along at 70 mph at just off idle and hardly any throttle like some of the yanks I've been in I cant see dropping to second to get it up to peak torque as being the best economy tip
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Dave-R
- Posts: 24752
- Joined: Sun Apr 18, 04 11:23 pm
- Location: Dave Robson lives in Geordieland
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You don't have to Bananarama! believe me. If you can't get your Bananarama! head around it then just Bananarama! off and do what you want. It's not my Bananarama! money. 
It isn't at exactly peak torque anyway. I lied. But it is near enough as damn it. And peak torque is easier to find. So Bananarama! off you Bananarama!.
Sorry. Just been watching "Sexy Beast" and I'm still in character.
I am always like that after watching a good film closely.
That Ben Kingsley was good in it.
It isn't at exactly peak torque anyway. I lied. But it is near enough as damn it. And peak torque is easier to find. So Bananarama! off you Bananarama!.
Sorry. Just been watching "Sexy Beast" and I'm still in character.
I am always like that after watching a good film closely.
That Ben Kingsley was good in it.
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MilesnMiles
- Posts: 7309
- Joined: Fri Nov 04, 05 8:40 pm
- Location: Cornwall
Dave, you said
'You also want to make sure you are above the stall speed of the converter. '
Is that because at just off idle the carb isthrowing in fuel that isnt being used efficiently, whereas dropping a gear and running at say, 3,000 rpm (peak torque for instance) is better?
It makes sense to me in that my plugs are much sootier after growling around town at low revs than they are after a thrash up the motorway, strip etc..
ps Dont answer if you are still in 'Sexy Beast' mode
'You also want to make sure you are above the stall speed of the converter. '
Is that because at just off idle the carb isthrowing in fuel that isnt being used efficiently, whereas dropping a gear and running at say, 3,000 rpm (peak torque for instance) is better?
It makes sense to me in that my plugs are much sootier after growling around town at low revs than they are after a thrash up the motorway, strip etc..
ps Dont answer if you are still in 'Sexy Beast' mode