Before speed limiters!

[chris_webb]

Fergie47:
Well, somewhere along the line I really missed out. I started driving in 1968, with all manor of wagons,too many to mentioned here, but, including owning both an F89 and Transcon, neither of which, if memory serves, did more than 65 mph…I conclude, that every vehicle I ever drove/owned, was either fitted with standard diff ratio’s, or the wagons mentioned on here were fitted with high, in some cases, very high rear axle/ gearbox ratios. What I don’t recall was, that with either the Transcon or 89 freighted, that much went passed me…
I can’t begin to imagine what driving a lorry (older-pre-limiter days) lorry, in excess of 70-80-90 and even a 100mph must be like, pretty frightening I would imagine,especially trying to stop it, the brakes on the Transcon scared the crap out of me at a “sedate” 60…

You are spot on about the Transcon brakes Fergie,they were rubbish when running as a solo 4-wheeler,far better with a trailer on.

[harry]

Had a DAF on a Dutch firm with a coach back axle. Would cruise at 80,after that the motor would go quiet & the motoring got really serious. Got nicked,of course!

[fergie47]

Chris Webb:

You are spot on about the Transcon brakes Fergie,they were rubbish when running as a solo 4-wheeler,far better with a trailer on.

Yes Chris…best a 4 axle one at that…however, it always past the plateing with no problems…

[flip]

My R reg 1626 Merc (with the backwards 12 speed box) was good for 80ish on the flat but if “there is a greenhill far away” came on the radio I had to drop a couple of cogs . Running the old National from Rouen back to Calais at 38 tonnes was a real arm and leg worker…but happy days nonetheless.

[wheeltapper]

Remember about 1988 going out to an F12 from the emerald isle late one sunday night/monday morning north of Lancaster on the M6 south when I was a Volvo call out technician as the fuel pump drive shims had gone, put a new set on then timed the engine up with dial gauge and nipped all the bolts up.

Said to driver I will follow you down to Forton services in the van just to make sure everything is ok, as I will come off there as my bleeper had gone off again and I would be coming off the motorway there to phone Action VOLVO.

His reply (YOU CAN TRY SON, COACH DIFF & OPENED UP PUMP) SWINGING BEEF TO DELIVER

He was right, Hi Top Citroen Van was no match, left me for dead, I was doing 75 ish, he left me in the dust.

Met the same driver a few months later when his water pump failed and he told me it was going better than ever after timing the pump up using the dial gauge and not just the timing lines.

He would not tell me what it would do, but I suspect it was rarely in the inside lane.

[revman]

First marathon I had was British Leyland demo,to date it is the fastest motor I ever had 83mph,I did warrington via M62 & gave the B.L. Driver a lift back to lanc ,with 20ton of steel billets I didn’t open it up,but coming back m/t with a clear night boy did it go,but our fleet engineer,ordered them with a low diff,they would just do sixty,later on we had marathon2 with the intermediate diff 70mph motors,bit different tday paddling about at 56 (if you’re lucky)

[gazzer]

“The Joker” was fitted from new with a double reduction diff, giving 90kph at 1450rpm. I swapped it for a “coach” diff. Single reduction…2.78■■ and that gave 90 kph at 1150rpm. A top speed, or the most I got out of it before I run out of road was 94MPH between J1 and 2 of the M27 one Sunday morning. Right off the clock but it had a fuel consumption computer display. It improved the mpg by 0.5mpg. But at much reduced engine noise…with a straight thru stack!

[newmercman]

[ZB], I don’t know what the specific final drive ratio on the TurboStar was, but it had a 13speed Fuller, don’t know if that was a single or double overdrive, tyres were 315/80s. It did 100km/h at 1200rpm or thereabouts, so with overdrive gearing 100mph is feasible with a 2100rpm limit

I have very fond memories of that lorry and the service I got from it led me back to IVECO more than once as time went on. It started out its life in Ireland (which could mean a different spec) I got the lorry for free as I sold a brace of lorries, I got a bit of profit and the TurboStar as my end of the deal To be honest it was a dog when i got it, rotten as a month old pear, the rear springs were soggy and it never had a legal tyre on it, but a shot blast and a very good (and expensive) paintjob by Lancaster Mercedes in West Thurrock, two new rear springs and a set of Michelins all round and it became a proper little gem.

I put a set of Eminox chimneys on it after ripping the factory exhaust off whilst getting off a boat in Brindisi, no linkspan in those days so they levelled the ramp out with coconut matting, only they never used enough and as I was in pole position I was the unlucky Guinea Pig, much shouting and arm waving ensued and then the Italians turned up The shipping line paid for the price of a new exhaust as quoted by the local dealer, which was by this time a big drum type device (much dearer than the old style silencer on mine ) the Eminox only worked out a couple of hundred quid more, so on they went, they ran a single stack from each turbo, so it sounded like a four pot with a bad miss from inside the cab, until the roof hatch was popped open, then the true V8 music was heard, and boy did that thing sound sweet, thanks to regular visits to Italian mechanics to set timing and keep the valves in adjustment, this was recommended to me by our very own Keith the Thief

Apart from the initial outlay and regular changes of Rotella and filters, I never changed a bulb on that thing and it flew through the MOT every time, the only thing I can remember going wrong on it was the driver’s side wiper stripping the spline and I fixed that with a tube of superglue in a snow storm in Germany It also busted a couple of wheel studs in Hengelo NL in another snowstorm as I was en route to Denmark, this time I needed help as I had no super glue and a very friendly IVECO garage came out with a unit to drag my trailer in with and I bobtailed to the garage where the owner (who lived upstairs) donned his overalls and had me rolling again with a few hours of me making the phone call to IVECO

[fergie47]

newmercman:
[ZB], I don’t know what the specific final drive ratio on the TurboStar was, but it had a 13speed Fuller, don’t know if that was a single or double overdrive, tyres were 315/80s. It did 100km/h at 1200rpm or thereabouts, so with overdrive gearing 100mph is feasible with a 2100rpm limit

I have very fond memories of that lorry and the service I got from it led me back to IVECO more than once as time went on. It started out its life in Ireland (which could mean a different spec) I got the lorry for free as I sold a brace of lorries, I got a bit of profit and the TurboStar as my end of the deal To be honest it was a dog when i got it, rotten as a month old pear, the rear springs were soggy and it never had a legal tyre on it, but a shot blast and a very good (and expensive) paintjob by Lancaster Mercedes in West Thurrock, two new rear springs and a set of Michelins all round and it became a proper little gem.

I put a set of Eminox chimneys on it after ripping the factory exhaust off whilst getting off a boat in Brindisi, no linkspan in those days so they levelled the ramp out with coconut matting, only they never used enough and as I was in pole position I was the unlucky Guinea Pig, much shouting and arm waving ensued and then the Italians turned up The shipping line paid for the price of a new exhaust as quoted by the local dealer, which was by this time a big drum type device (much dearer than the old style silencer on mine ) the Eminox only worked out a couple of hundred quid more, so on they went, they ran a single stack from each turbo, so it sounded like a four pot with a bad miss from inside the cab, until the roof hatch was popped open, then the true V8 music was heard, and boy did that thing sound sweet, thanks to regular visits to Italian mechanics to set timing and keep the valves in adjustment, this was recommended to me by our very own Keith the Thief

Apart from the initial outlay and regular changes of Rotella and filters, I never changed a bulb on that thing and it flew through the MOT every time, the only thing I can remember going wrong on it was the driver’s side wiper stripping the spline and I fixed that with a tube of superglue in a snow storm in Germany It also busted a couple of wheel studs in Hengelo NL in another snowstorm as I was en route to Denmark, this time I needed help as I had no super glue and a very friendly IVECO garage came out with a unit to drag my trailer in with and I bobtailed to the garage where the owner (who lived upstairs) donned his overalls and had me rolling again with a few hours of me making the phone call to IVECO

I worked at the local IVECO dealer in Southampton. I remember we supplies a V8 Turbo Star to a local owner driver, Graham Richardson. It was either an ex show motor or special edition, with chrome stacks and bumper, extra this and that, really a nice motor.
After prepping it, we hooked it under a tri-axle test trailer, we had a “test-route” about 10 miles, which included a bit of everything, and this was the first V8 wagon I’d driven. After leaving the garage there was a T juntion, which ment you never got a run up a really steep hill about three quarters of a mile drag up to a roundabout. To say I was stunned was an understatement, it pulled up that hill as if it was empty, changing up all the time through the 12 speed fuller, at what at the time, seemed such low rev’s, till I got to the roundabout, I’d not done that test route with such ease before, and don’t re-call doing it again. In it’s time, early eighties, it was the dogs…
Not sure what ever happened to it, someone said it was parked up for sometime later on in in its life looking rather sorry for its self, maybe it got rescued, but probably cut up just for the engine…

[carryfast]

[zb]
anorak:
I read somewhere- possibly in Commercial Motor, when they had proper technical articles in it- that it used to take 200bhp to make a 38 tonner do 60mph, of which half was wind resistance and the other half rolling resistance. I can’t remember if that was with a flat or box trailer, or if any air management devices were fitted. Either way, it means that it would take 630bhp to make the same vehicle do 100mph. This makes the reasonably sound assumption that rolling resistance is constant, and that wind resistance is proportional to the cube of speed. The solo tractor unit, assuming an unladen weight of 8 tons, that rolling resistance is proportional to weight and the wind drag is unchanged from that with the trailer on, would require 500bhp to do 100mph. A slight downhill gradient will obviously be of benefit to lower-powered vehicles, in their quest to reach the ton! Of course, the governor on the engine must allow enough revs and the gear ratio must be “tall” enough. Newmercman- can you remember what gear ratio your Turbostar had?

I think you need to factor inertia,amongst other variables,into that.Which probably brings that figure down.If you can put enough power down on the ground for long enough the sheer inertia starts to overcome air resistance ( to a point ) in just the same way that a parachute,of a given size,won’t slow down a 38 tonner from 100 mph as easily/quickly as it would a 10 tonner.I’m going to be controversial,as usual,in betting that it would take forever to accelerate a 38 tonner with 200 hp up to 60 mph if it’s even possible.Whereas I’d bet that it wouldn’t be too difficult to do that with less than 630 hp depending on exactly how much of the power actually gets put on the ground and isn’t taken out in transmission losses etc.I think there’s enough documented history from across the Atlantic in the case of regular 100 mph running with at least CAT 3408,Detroit 8V92 or 12V71,and ■■■■■■■ KTA powered wagons which would probably support that.In which the general measure of speed wasn’t always just what the speedometer said but how horizontal the CB antennas were in the air flow.IE the flatter the faster.

[zb_anorak]

Carryfast:
the sheer inertia starts to overcome air resistance

Put more weight on to reduce wind resistance? FFS

[carryfast]

[zb]
anorak:

Carryfast:
the sheer inertia starts to overcome air resistance

Put more weight on to reduce wind resistance? FFS

So you’re saying that you could slow that 38 tonner down as quick from 100 mph using the same size parachute as a 10 tonner .If not why not.

Given a long and flat enough piece of road I’d bet that I’d have more chance of running an unlimited 38 tonner,up to 100 mph,pulled by something with ( a lot ) less than 630 hp than up to 60 mph with just 200 hp.Regardless of what CM’s theoretical calculations on paper say.

By the way I think the bang here was caused by the same issue of weight combined with speed overcoming air resistance type equation unless you’re saying that it would have been no different if it had just weighed 1 kg instead of 1000,s.

youtube.com/watch?v=sCFQbJuRoCs

[zb_anorak]

Carryfast:

[zb]
anorak:

Carryfast:
the sheer inertia starts to overcome air resistance

Put more weight on to reduce wind resistance? FFS

So you’re saying that you could slow that 38 tonner down as quick from 100 mph using the same size parachute as a 10 tonner .If not why not.

The original post was about the steady state speed achievable by driving along a level road, not descent speed when thrown out of an aeroplane. Every other poster has understood this, without needing to be corrected.

Carryfast:
Given a long and flat enough piece of road I’d bet that I’d have more chance of running an unlimited 38 tonner,pulling a boxvan trailer,up to 100 mph,pulled by something with ( a lot ) less than 630 hp than up to 60 mph with 200 hp.Regardless of what CM’s theoretical calculations on paper say.

Ignore the logic; that difficult schooboy maths can’t begin to explain anything, can it? In case of ignorance trust anecdote, instinct and superstition.

How many more posts will it take before the simple idea of a vehicle’s top speed is made fully incomprehensible by twisting Margeret Thatcher into the argument?

[carryfast]

[zb]
anorak:

Carryfast:

[zb]
anorak:

Carryfast:
the sheer inertia starts to overcome air resistance

Put more weight on to reduce wind resistance? FFS

So you’re saying that you could slow that 38 tonner down as quick from 100 mph using the same size parachute as a 10 tonner .If not why not.

The original post was about the steady state speed achievable by driving along a level road, not descent speed when thrown out of an aeroplane. Every other poster has understood this, without needing to be corrected.

Carryfast:
Given a long and flat enough piece of road I’d bet that I’d have more chance of running an unlimited 38 tonner,pulling a boxvan trailer,up to 100 mph,pulled by something with ( a lot ) less than 630 hp than up to 60 mph with 200 hp.Regardless of what CM’s theoretical calculations on paper say.

Ignore the logic; that difficult schooboy maths can’t begin to explain anything, can it? In case of ignorance trust anecdote, instinct and superstition.

How many more posts will it take before the simple idea of a vehicle’s top speed is made fully incomprehensible by twisting Margeret Thatcher into the argument?

Who said anything about being thrown out of an aeroplane.It’s common in many applications for parachutes to be used instead of brakes to slow down fast moving vehicles.The question asked was are you saying in that case that you could slow down a 38 tonner from 100 mph as quick as a 10 tonner using the same size parachute if not why not.

[zb_anorak]

Carryfast:
Who said anything about being thrown out of an aeroplane.

You did. You brought up the subject of parachutes. They are used on aeroplanes.

Carryfast:
It’s common in many applications for parachutes to be used instead of brakes to slow down fast moving vehicles.

No it isn’t.

Carryfast:
The question asked was are you saying in that case that you could slow down a 38 tonner from 100 mph as quick as a 10 tonner using the same size parachute if not why not.

No. Irrelevant question, anyway.

[carryfast]

[zb]
anorak:

Carryfast:
Who said anything about being thrown out of an aeroplane.

You did. You brought up the subject of parachutes. They are used on aeroplanes.

Carryfast:
It’s common in many applications for parachutes to be used instead of brakes to slow down fast moving vehicles.

No it isn’t.

Carryfast:
The question asked was are you saying in that case that you could slow down a 38 tonner from 100 mph as quick as a 10 tonner using the same size parachute if not why not.

No. Irrelevant question, anyway.

Parachutes rely on the principle of using air resistance and drag to slow down fast moving objects.

They are used in many types of specialist applications including vehicles in racing applications.It’s obvious that the amount of drag provided by a parachute is dependent on it’s type/size.

Youv’e already admitted that a 38 tonner can’t be slowed down at the same rate as a 10 tonner,using the same type/size parachute and therefore drag.Assuming that weight won’t,at least to some extent,overcome air resistance,why not .

[zb_anorak]

Carryfast:
Youv’e already admitted that a 38 tonner can’t be slowed down at the same rate as a 10 tonner,using the same type/size parachute and therefore drag.

I also said that it is irrelevant. The top speed of a vehicle is a constant speed, so there is no acceleration and therefore inertia does not enter into it.

Carryfast:
“Inertia overcomes wind resistance,”

is what you said initially. That is wrong, and ridiculous. On that principle, you would have F1 teams adding ballast to improve the top speed of their cars. Airlines would pay passengers to carry excess baggage. Hauliers would charge less for carrying heavier loads.

Everyone else on this forum understands how speed, weight and power interract, without a murmur of protest. Why not you? Any schoolgirl, when presented with your attempts to grapple with basic physics, would laugh her socks off. I have noticed that Google finds posts on Trucknet. It is only a matter of time before someone, unconnected with old lorries, discovers your pronouncements and sets up a blog of them for a laugh. It may have already happened.

[carryfast]

[zb]
anorak:

Carryfast:
Youv’e already admitted that a 38 tonner can’t be slowed down at the same rate as a 10 tonner,using the same type/size parachute and therefore drag.

I also said that it is irrelevant. The top speed of a vehicle is a constant speed, so there is no acceleration and therefore inertia does not enter into it.

Carryfast:
“Inertia overcomes wind resistance,”

is what you said initially. That is wrong, and ridiculous. On that principle, you would have F1 teams adding ballast to improve the top speed of their cars. Airlines would pay passengers to carry excess baggage. Hauliers would charge less for carrying heavier loads.

Everyone else on this forum understands how speed, weight and power interract, without a murmur of protest. Why not you? Any schoolgirl, when presented with your attempts to grapple with basic physics, would laugh her socks off. I have noticed that Google finds posts on Trucknet. It is only a matter of time before someone, unconnected with old lorries, discovers your pronouncements and sets up a blog of them for a laugh. It may have already happened.

Notwithstanding all the obvious misunderstanding of what is meant by variables and the role that inertia and acceleration have in all the combined aspects that are involved in getting the thing up to that top speed in the first place.It still leaves the issue as to wether you’d like to take that bet that it would be far more likely that something like a Fiat V8,let alone something with a CAT 3408 or ■■■■■■■ KTA etc,with ( a lot ) less than 630 hp,would be able to ‘accelerate’ a 38 tonner up to 100 mph ( eventually ) given enough flat road.Than something with just 200 hp could accelerate it up to 60 mph.Remembering that as I said top speed is nothing without the acceleration needed to get it there in the first place.Which is one of the reasons why that F1 car doesn’t carry around 37.5 tonnes of ballast.

[zb_anorak]

Carryfast:
Notwithstanding all the obvious misunderstanding

Is this an admission?

[carryfast]

[zb]
anorak:

Carryfast:
Notwithstanding all the obvious misunderstanding

Is this an admission?

I meant misunderstandings on your part.An answer to the questions related to the parachute example and the bet regarding the 200 hp unit being able to pull a 38 tonner up to 60 mph v the less than 630 hp one being able to pull it up to 100 mph will do.