1/4 mile question terminal speed
Discussion
I managed an 11.9 and from memory about 123mph in my old 4l Tuscan, it really upset a drag team with a hugely modified Capri with parachute big wheels etc etc they only did 12.5.
That said most of my runs were mid 12s and the 11.9 just really hooked up well.
I would say though it was bloody scary almost as on most runs I had slight wheel spin over the WHOLE of the 1/4 even in fourth gear.
Was good fun though
That said most of my runs were mid 12s and the 11.9 just really hooked up well.
I would say though it was bloody scary almost as on most runs I had slight wheel spin over the WHOLE of the 1/4 even in fourth gear.
Was good fun though
Welshbeef said:
My old fiat coupe 20v turbo with 220bhp and 1200kg had a 1/4 mile terminal velocity of 98mph. So the question I have is how much faster is 12mph over a 1/4 mile? Is that a big big difference? I'm not sure how to quantify it as Ive never really taken much interest in 1/4miles apart from knowing a 11 second road car is pretty nippy while run of the mill GTI could be 18 seconds
It's a simple time/distance calculation. With your car at 98mph and the other at 110mph, the faster car would be somewhere in the region of 67 meters ahead of you. Quite a lot really!Kozy said:
Welshbeef said:
My old fiat coupe 20v turbo with 220bhp and 1200kg had a 1/4 mile terminal velocity of 98mph. So the question I have is how much faster is 12mph over a 1/4 mile? Is that a big big difference? I'm not sure how to quantify it as Ive never really taken much interest in 1/4miles apart from knowing a 11 second road car is pretty nippy while run of the mill GTI could be 18 seconds
It's a simple time/distance calculation. With your car at 98mph and the other at 110mph, the faster car would be somewhere in the region of 67 meters ahead of you. Quite a lot really!
AdeTuono said:
Not from a standing start and with differing reaction times it isn't. Unless you're quoting a measured flying 1/4 at a constant speed, which wasn't the question.
No, that is from a standing start, traction limited with no wheel spin. It's simulated so same reaction times.OK I jest, it wasn't simple at all. There are a lot of variables but generally you'll be looking at around 50-70 meters gap. That's easier to understand than '12mph more after 402 meters'.
Terminal speed has little bearing on how close the cars will be at the finish line.
For example a 2005 s197 Mustang GT with tune, street ET's, exhaust and an induction kit running 4.10:1 find drive could pull a 12.4 @ 104mph while a stock 2001 Camaro z28 manual might pull a 13.1 @ 109mph.
This means from a standing start at the strip the Mustang will cross the line first. However out on the open roads going from a roll the Camaro is going to be in the lead.
For example a 2005 s197 Mustang GT with tune, street ET's, exhaust and an induction kit running 4.10:1 find drive could pull a 12.4 @ 104mph while a stock 2001 Camaro z28 manual might pull a 13.1 @ 109mph.
This means from a standing start at the strip the Mustang will cross the line first. However out on the open roads going from a roll the Camaro is going to be in the lead.
So really you'd want to for petrol heads aim for a car with the highest terminal speed - then modify it to sort out the traction or have fun with it being loose.
Anyone have an F40 1/4 mile I cannot find it incl terminal speed
Also what would a 1/4 mile time and speed be for a RS200 group B rally car up to the max.
Anyone have an F40 1/4 mile I cannot find it incl terminal speed
Also what would a 1/4 mile time and speed be for a RS200 group B rally car up to the max.
Welshbeef said:
So really you'd want to for petrol heads aim for a car with the highest terminal speed - then modify it to sort out the traction or have fun with it being loose.
Anyone have an F40 1/4 mile I cannot find it incl terminal speed
Also what would a 1/4 mile time and speed be for a RS200 group B rally car up to the max.
According to Wikipedia the RS200 is 11.4 @ 115mph. Although spec and power of a Grp B vehicle can vary greatly.Anyone have an F40 1/4 mile I cannot find it incl terminal speed
Also what would a 1/4 mile time and speed be for a RS200 group B rally car up to the max.
Drag Times says 11.7 @ 125mph for the F40.
A stock Escort Cosworth is around 14.5 @ 95mph
e46 M3 13.2 @ 105mph
Simple rule of thumb for drag racing...
200-300bhp = 100-110mph
300-400bhp = 105-115mph
400-500bhp = 115-125mph
500-600bhp = 125-135mph
600-700bhp = 130-140mph
Transmission type has an effect as does weight of the car. Generally DSG type transmissions will be at the upper end of those scales, manual types at the lower ends. Also, weight is a factor, Nissan GTR's (MY12 with 550hp) only trap 125mph because of their 1750kg bulk but a TTRS with say 450bhp can trap the same 125mph due to weighing 1450kg. (Both have same twin clutch transmissions, PWR figures for 550/1750 vs 450/1450 near identical)
But as a general rule of thumb on normal weight cars, circa 1500kg the speeds above are quite accurate.
200-300bhp = 100-110mph
300-400bhp = 105-115mph
400-500bhp = 115-125mph
500-600bhp = 125-135mph
600-700bhp = 130-140mph
Transmission type has an effect as does weight of the car. Generally DSG type transmissions will be at the upper end of those scales, manual types at the lower ends. Also, weight is a factor, Nissan GTR's (MY12 with 550hp) only trap 125mph because of their 1750kg bulk but a TTRS with say 450bhp can trap the same 125mph due to weighing 1450kg. (Both have same twin clutch transmissions, PWR figures for 550/1750 vs 450/1450 near identical)
But as a general rule of thumb on normal weight cars, circa 1500kg the speeds above are quite accurate.
Edited by MitchyRS on Wednesday 19th September 11:51
There were a few inaccuracies with last nights show, which I watched cringing at Mike Brewers 'test drive'...
The guy selling it claimed it was a 6.3 litre and then Ed described it as a 350ci, which is actually a 5.7litre. Wouldn't mind knowing what it actually was. Although at 6.3 I'd imagine that was a stroker?
The guy selling it claimed it was a 6.3 litre and then Ed described it as a 350ci, which is actually a 5.7litre. Wouldn't mind knowing what it actually was. Although at 6.3 I'd imagine that was a stroker?
Welshbeef said:
Just having watched wheeler dealers eth the cobra kit car 6.3 ltr v8 370bhp and 600kg or whatever they achieved a terminal speed of 108 & 110mph - clearly a racing driver would have beaten that by some margin but let's say it does 110mph at that distance.
My old fiat coupe 20v turbo with 220bhp and 1200kg had a 1/4 mile terminal velocity of 98mph. So the question I have is how much faster is 12mph over a 1/4 mile? Is that a big big difference? I'm not sure how to quantify it as Ive never really taken much interest in 1/4miles apart from knowing a 11 second road car is pretty nippy while run of the mill GTI could be 18 seconds
Wasn't this explained to you in an old thread when you compared a 335d BMW to a Subaru? It was a while ago so I'm a bit foggy.My old fiat coupe 20v turbo with 220bhp and 1200kg had a 1/4 mile terminal velocity of 98mph. So the question I have is how much faster is 12mph over a 1/4 mile? Is that a big big difference? I'm not sure how to quantify it as Ive never really taken much interest in 1/4miles apart from knowing a 11 second road car is pretty nippy while run of the mill GTI could be 18 seconds
Ozzie Osmond said:
Gearing is crucial for 1/4 mile times. If one car needs more gear changes than another it will almost certainly be slower. High torque cars tend to perform well for this reason - so long as you can get them off the line!!
I think some of the drag racers would disagree. A common mod on Fbody's and Mustangs is to ditch the factory final drive for a shorter one (so more gear changes) and reduced 1/4 mile times. 4.10:1 is common from the stock 3.42:1 (GM) and 3.55:1 (Ford). Here's a thought. There is a drag racing class called Super Gas where cars have to run 9.9 seconds. Most cars in the class are big-engine v8 cars with extremely wide tyres and 3-speed auto-boxes, and cross the finish line at just over 120mph.
There is also a class for FWD jap cars and there are cars in that class that also run 9.90 second ETs, but terminal speeds are well over 150mph.
The FWD cars are turbo, small-capacity and usually 6-speed gearboxes. They have less grip off the line, so compensate by pumping out huge power at the top-end.
Two ways of achieving the same ET. Very different physics.
There is also a class for FWD jap cars and there are cars in that class that also run 9.90 second ETs, but terminal speeds are well over 150mph.
The FWD cars are turbo, small-capacity and usually 6-speed gearboxes. They have less grip off the line, so compensate by pumping out huge power at the top-end.
Two ways of achieving the same ET. Very different physics.
300bhp/ton said:
iva cosworth said:
1/4 mile in a road car is hardly rocket science.
Launch,accelarate,change gear,accelarate,finish line.
A day at a RWYB and anyone can be an expert in their own car.
And with that .....Goodnight
So you've got timeslips to prove it then?Launch,accelarate,change gear,accelarate,finish line.
A day at a RWYB and anyone can be an expert in their own car.
And with that .....Goodnight
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