Hey, But don’t forget that by technical calculating there is Always a loss of speed by tyre hight empty
half or fully loaded, new, worn and used. The difference in ratio’s of the same box can be caused by how they calculate it.
That’s why in the beginning of limiters they went to the teststation with low pressure and worn tyres, to
gain some speed.
That does thinking me at the time there came 5/6 new 8 speed F88’s in the mid '60’s at the company the one was a bit faster as the other, and all made squabble you have the fastest. But as my father was a mechanist, he took the slowest and ended up with the fastest.
[zb]
anorak:
They had 1200x20 tyres, an RTO9509 gearbox and a 4.71:1 final drive. Is that correct?
EDIT:
1200x20 tyres; RT9095A with 4.64:1 final drive; then later in 1975 the RT9509 with 4.71:1 final drive. Remember that the suffix A simply denotes a different set of ratios. These figures are borne out by the successive NGC brochures issued by ERF over a period of years. I have some of them but not all. Robert
Hey, It looks that later even was used still a bit slower ratio, which made it even a little bit slower !!!
And would the latter box not be called RT9509C as in the Transcontinental ■■? Which had a slower crawler and
a wider gap between 4th and 5th which paved the way to use more the high crawler.
Eric,
I haven’t seen the RT9509C mentioned anywhere in connection with the NGC, Eric. I know other manufacturers like Dennison used it. Robert
I concede that CF was right from the start of this discourse in claiming that the NGC was under-geared for UK work. This reminds me of how it also worked the other way round. When the DAF DKSE version of the 2800 came out, they ditched the 13-sp Fuller. Instead, they put ZF 16-sp synchro 'boxes in their LHD units for European running, and put the RTO 9509A in their RHD models because our (then) higher speed limit of 60mph. It was geared to hit 66mph @1800 rpm. In 1982 they replaced it with the RTX 11609A for better meshing. So it wasn’t just ERF who played with the different needs of UK/EU!
This could lead to an exploration of other ‘export’ models that were differently spec’d: most of them, probably!.. Robert
This thread cracks me up ! Posted a rare road test that barely gets a mention,then a small piece from commercial motor that gets discussed for 3 pages ?
Anyway all this chatter about fuel economy and wheel bases,coupling up to trailers etc.Read this from
1975 which i am sure i sent to Robert who posted it on here sometime ago. It clearly states that the ERF
returned VERY RESPECTABLE ECONOMY,was FASTEST,and proved to be the most VERSATILE of the lot when
coupling to various different trailers !
Mind you the F89 was the choice for really tough conditions with the ERF next if very hilly conditions.
I would have said hilly conditions were tough conditions !! (Sorry Robert ! )
Click on page twice to read,ERF bit starts just above pic of Daf.
DEANB:
This thread cracks me up ! Posted a rare road test that barely gets a mention,then a small piece from commercial motor that gets discussed for 3 pages ?
Anyway all this chatter about fuel economy and wheel bases,coupling up to trailers etc.Read this from
1975 which i am sure i sent to Robert who posted it on here sometime ago. It clearly states that the ERF
returned VERY RESPECTABLE ECONOMY,was FASTEST,and proved to be the most VERSATILE of the lot when
coupling to various different trailers !
Mind you the F89 was the choice for really tough conditions with the ERF next if very hilly conditions.
I would have said hilly conditions were tough conditions !! (Sorry Robert ! )
Click on page twice to read,ERF bit starts just above pic of Daf.
0
This is what I was trying to assure CF about. In fact I quoted that page in Book 2 to make precisely that point. He’s right about the gearing but not about the economy when Continental running, I think: though he’s probably right in thinking that an NGC blasting up and down the M1 everyday would seem a tad thirsty! Thank you for reminding us about this piece! I feel I should add though, that it was written by Pat Kennett, who clearly had a very soft spot for this machine . Robert
If the standard gearbox was indeed the RT 9509 (Top speed 92-94km/h??, depending on whose tyre data you use. Thanks for that extra information, Tiptop ), it would not necessarily have been under-geared for UK motorway use. Many operators would have been happy to use the engine speed governor as a speed limiter- for example, Atkinson submitted their 8LXB Borderer for CM test with a geared top speed of 58mph, and it still broke their fuel consumption records, despite sitting at maximum revs/part load for much of the route. The ■■■■■■■ engine would have been much worse in this situation- look how its SFC curve rises towards maximum revs, whereas the Gardner’s is relatively flat. Would that have been sufficient reason for ERF’s initial reluctance to supply the UK market with NGC420s? Those operators wishing to break the speed limit (or with sufficiently disciplined drivers not to do so) could have insisted on the overdrive 'box, 9 or 13 speed.
I think the reasons for ERF not supplying NGC380 or 420s for domestic haulage are rooted in something other than component specifications.
Found this picture on an old thread, it was posted by Harry, the gent with the wrestler as his avatar, and the caption was “drove this heap for a Swiss company” looks like a ERF to me Robert?
robert1952:
I concede that CF was right from the start of this discourse in claiming that the NGC was under-geared for UK work. This reminds me of how it also worked the other way round. When the DAF DKSE version of the 2800 came out, they ditched the 13-sp Fuller. Instead, they put ZF 16-sp synchro 'boxes in their LHD units for European running, and put the RTO 9509A in their RHD models because our (then) higher speed limit of 60mph. It was geared to hit 66mph @1800 rpm. In 1982 they replaced it with the RTX 11609A for better meshing. So it wasn’t just ERF who played with the different needs of UK/EU!
This could lead to an exploration of other ‘export’ models that were differently spec’d: most of them, probably!.. Robert
My point was more a case that it was under geared regardless.Because 1) they were using max governed/peak power engine speed ( 2,000 rpm + ) as the reference point to base the max road speed requirement on and even worse 2) they seemed to have been using that erroneous idea as a form of speed limiter function. IE as I said we are looking for,at most,1,800 rpm,preferably less ,at ‘either’ 65 mph for UK spec ‘or’ at 90 kmh for Euro spec.The fact that might allow for considerably more road speed ‘if’ the driver chose to run it up to the full 2,100 rpm,in either case,was ( should have been ) irrelevant.
[zb]
anorak:
If the standard gearbox was indeed the RT 9509 (Top speed 92-94km/h??, depending on whose tyre data you use. Thanks for that extra information, Tiptop ), it would not necessarily have been under-geared for UK motorway use. Many operators would have been happy to use the engine speed governor as a speed limiter- for example, Atkinson submitted their 8LXB Borderer for CM test with a geared top speed of 58mph, and it still broke their fuel consumption records, despite sitting at maximum revs/part load for much of the route. The ■■■■■■■ engine would have been much worse in this situation- look how its SFC curve rises towards maximum revs, whereas the Gardner’s is relatively flat. Would that have been sufficient reason for ERF’s initial reluctance to supply the UK market with NGC420s? Those operators wishing to break the speed limit (or with sufficiently disciplined drivers not to do so) could have insisted on the overdrive 'box, 9 or 13 speed.
I think the reasons for ERF not supplying NGC380 or 420s for domestic haulage are rooted in something other than component specifications.
In the case of something with the the Gardner’s output there wasn’t much choice but to gear for max speed at around peak power.However that all changes in the case of a 14 litre turbocharged ■■■■■■■ in that peak power type engine speeds need to be avoided wherever possible and definitely in the case of normal motorway running.For the reasons you’ve noted.Make no mistake the thing could only have been a fuel consumption liability running at a sustained 2,000 rpm +.As for ERF’s reluctance to supply the NGC here.More like what had to be a massive argument within the firm regarding what its designer had actually called for as opposed to what they actually built and seemingly having somehow having put all their eggs in one basket of the wrong gearbox and final drive combination.Partly on the advice of muddle headed continental market demands and some strange definition of the idea of ‘assembly’ operation,regardless of market. Thereby defeating one of the main advantages of the assembly model.IE design intent meets confused customer thinking and what seems like a silly limited component buying policy.
On that note it would be interesting to find out how they geared their much later offerings involving the big cam ■■■■■■■■■■■■ my bet that the idea of using max governed engine speed as the reference for max road speed let alone adding insult to injury of using that idea as a speed limiter,went out the window where it belonged.Based on the fact that before speed limiters the only option was to trust the driver to not run at silly speeds.Which in this case simply meant fitting it with the RTO box either 13 or 9 speed or the choice of either.Or doing what its designer had actually called for in the form of RT box and a higher final drive.
DEANB:
This thread cracks me up ! Posted a rare road test that barely gets a mention,then a small piece from commercial motor that gets discussed for 3 pages ?
Anyway all this chatter about fuel economy and wheel bases,coupling up to trailers etc.Read this from
1975 which i am sure i sent to Robert who posted it on here sometime ago. It clearly states that the ERF
returned VERY RESPECTABLE ECONOMY,was FASTEST,and proved to be the most VERSATILE of the lot when
coupling to various different trailers !
Mind you the F89 was the choice for really tough conditions with the ERF next if very hilly conditions.
I would have said hilly conditions were tough conditions !! (Sorry Robert ! )
Click on page twice to read,ERF bit starts just above pic of Daf.
0
This is what I was trying to assure CF about. In fact I quoted that page in Book 2 to make precisely that point. He’s right about the gearing but not about the economy when Continental running
It’s difficult to understand how the economy could have been anything but a liability regarding a turbocharged ■■■■■■■ running at a sustained 2,000 rpm +.Thereby totally defeating the object of the high torque turbocharged engine.When the same road speed could have been obtained at a much lower engine speed with the correct gearing. Bearing in mind that Pat Kennett obviously didn’t have the luxury of an RTO equipped NGC to compare the RT equipped version with in that regard.
[zb]
anorak:
If the standard gearbox was indeed the RT 9509 (Top speed 92-94km/h??, depending on whose tyre data you use. Thanks for that extra information, Tiptop ), it would not necessarily have been under-geared for UK motorway use. Many operators would have been happy to use the engine speed governor as a speed limiter- for example, Atkinson submitted their 8LXB Borderer for CM test with a geared top speed of 58mph, and it still broke their fuel consumption records, despite sitting at maximum revs/part load for much of the route. The ■■■■■■■ engine would have been much worse in this situation- look how its SFC curve rises towards maximum revs, whereas the Gardner’s is relatively flat. Would that have been sufficient reason for ERF’s initial reluctance to supply the UK market with NGC420s? Those operators wishing to break the speed limit (or with sufficiently disciplined drivers not to do so) could have insisted on the overdrive 'box, 9 or 13 speed.
I think the reasons for ERF not supplying NGC380 or 420s for domestic haulage are rooted in something other than component specifications.
Perhaps the prohibitive cost of producing a RHD version. I have already recorded on this thread ERF’s complaint that producing Euro-trucks in small numbers was considered unrealistically expensive, which is why they pulled out of Europe in the late '70s. Robert
pete smith:
Found this picture on an old thread, it was posted by Harry, the gent with the wrestler as his avatar, and the caption was “drove this heap for a Swiss company” looks like a ERF to me Robert?
Ah! Don’t worry Pete, this picture featured very early in the thread and ‘Harry’ blogged vociferously about it. In fact, he was about the only bloke I’ve communicated with who disliked this model! He worked for H Burkhard of Zurich but had a lot of trouble with what sounded like an ill-maintained truck! ‘Harry’ was nonetheless very informative and made some fantastic contributions to the TNUK forum. He’s ‘off air’ now, but David Millar assures us that he’s still with us. Thanks for posting. Robert
[zb]
anorak:
If the standard gearbox was indeed the RT 9509 (Top speed 92-94km/h??, depending on whose tyre data you use. Thanks for that extra information, Tiptop ), it would not necessarily have been under-geared for UK motorway use. Many operators would have been happy to use the engine speed governor as a speed limiter- for example, Atkinson submitted their 8LXB Borderer for CM test with a geared top speed of 58mph, and it still broke their fuel consumption records, despite sitting at maximum revs/part load for much of the route. The ■■■■■■■ engine would have been much worse in this situation- look how its SFC curve rises towards maximum revs, whereas the Gardner’s is relatively flat. Would that have been sufficient reason for ERF’s initial reluctance to supply the UK market with NGC420s? Those operators wishing to break the speed limit (or with sufficiently disciplined drivers not to do so) could have insisted on the overdrive 'box, 9 or 13 speed.
I think the reasons for ERF not supplying NGC380 or 420s for domestic haulage are rooted in something other than component specifications.
Perhaps the prohibitive cost of producing a RHD version. I have already recorded on this thread ERF’s complaint that producing Euro-trucks in small numbers was considered unrealistically expensive, which is why they pulled out of Europe in the late '70s. Robert
In the light of Anorak’s post, it might be better to focus on the ‘inconvenience factor’ of running at a max speed of 58mph in Britain at a time when lorries were doing considerably more than this, rather than focussing on the ‘economy factor’, especially as records seem to show that this latter factor was not really an issue. We all know the well-rehearsed arguments about fast lorries drinking more fuel; and about slow lorries not achieving time schedules (thus losing revenue). But in the case of the NGC it was clearly never a serious issue because:
a) It was an export lorry designed for Continental use
b) When operated from a UK base it was bound to spend most of its working life abroad because it was a LHD-only long-hauler
In other words, it was never really going to be an issue if a Middle-East bound NGC was a bit ‘slow’ at 59mph down the M2 to Dover or even if it cost a gallon or two more of diesel because it would actually earn its real keep doing a return journey to Baghdad, which is exactly what it was designed to do. Robert
robert1952:
In the light of Anorak’s post, it might be better to focus on the ‘inconvenience factor’ of running at a max speed of 58mph in Britain at a time when lorries were doing considerably more than this, rather than focussing on the ‘economy factor’, especially as records seem to show that this latter factor was not really an issue. We all know the well-rehearsed arguments about fast lorries drinking more fuel; and about slow lorries not achieving time schedules (thus losing revenue). But in the case of the NGC it was clearly never a serious issue because:
a) It was an export lorry designed for Continental use
b) When operated from a UK base it was bound to spend most of its working life abroad because it was a LHD-only long-hauler
In other words, it was never really going to be an issue if a Middle-East bound NGC was a bit ‘slow’ at 59mph down the M2 to Dover or even if it cost a gallon or two more of diesel because it would actually earn its real keep doing a return journey to Baghdad, which is exactly what it was designed to do. Robert
The idea was to make a quick truck which could maintain high average speeds throughout the ‘European’ road/motorway network while using the high torque turbo engine design to minimise fuel costs doing it.In which case the idea of using max governed peak power type engine speed as a gearing reference point for maximum intended road speed,whether 60 mph or 90 kmh, totally defeats the object of that.On that note while it was often ‘used’ on Middle East routes it was actually ‘designed’ as a European general hauler and in terms of correct gearing the former not being mutually exclusive with the latter.IE using the RTO box to gear it at or even less than 1,800 rpm at 90 kmh wouldn’t have been mutually exclusive with UK use or Euro use or Middle East use.Unlike gearing it at 2,000 rpm + at around 90 kmh which which would explain why it never met anything like its true potential as a general long haul vehicle regardless of market.
In which case I’d guess that ERF never continued with the idea of using max governed ‘engine speed’,as a gearing reference for maximum required ‘road speed’,on later types ?.Or for that matter the strange idea and policy of offering direct drive top Fuller only regardless of final drive choice ?.
A couple of pages back Eric reminded us that this was pretty normal in the '70s and he mentioned that Scanias at that time Scania’s were geared in Belgium to 90 @ 2100rpm (110 or 140) with 4.71 ratio and no overdrive gearbox. He went on to say that even Volvo with the 8 speed box was reving 2200 @ 90 but all drove at 2400/2500 revs. Robert
robert1952:
A couple of pages back Eric reminded us that this was pretty normal in the '70s and he mentioned that Scanias at that time Scania’s were geared in Belgium to 90 @ 2100rpm (110 or 140) with 4.71 ratio and no overdrive gearbox. He went on to say that even Volvo with the 8 speed box was reving 2200 @ 90 but all drove at 2400/2500 revs. Robert
It’s probably fair to say that most manufacturers and customers were understandably ignorant of the finer points of gearing a big power ( more importantly big torque ) truck properly in the early 1970’s.However it really wasn’t rocket science by the mid 1970’s as to what was needed and probably no excuses for not understanding that sooner rather than later and thereby getting a head start over the opposition and thereby making far more effective use of the advantages of the turbo ■■■■■■■■■■■■■■■ small cam or big cam the torque characteristics being as close as made no difference in either case.
The comments here,regarding the Scania 141’s revised gearing say it all in that regard.In addition to the well known ‘issues’ regarding the long overdue in getting the gearing right in the case of the ■■■■■■■■
On that note it’s obvious that counting out the use of the RTO Fuller at least in the case of the limited final drive options of the NGC was a stupid move.Which no surprise seems to have been reversed not long after in future models whether Roadranger ‘O’ type.Or the Twin Splitter ‘O’ type even seemingly with Rockwell being more or less ERF’s main axle supplier by that point ?.
As for the NGC they had a perfect opportunity to combine the best aspects of both the 6 cylinder and V8 Scanias ( 6 cylinder simplicity with V8 type torque ) in one truck and effectively blew it in terms of both engine and driveline choice and failure to develop the steel cab model.
Carryfast:
If I’ve got it right U v H shift pattern denotes RTO v RT ?.While top always remains direct in the case of RT regardless ?.
Don’t think so. At least 2 versions of the direct-top RT seem to have had the ‘U’-shift and ‘H’-shift respectively. Robert
When comparing the two versions of the same gearbox, say the 9509, Carryfast is entirely correct.
If you are comparing the 9509 with a different gearbox, say the 9515, then Robert is correct.
As I said on the other thread about gearboxes, these were standard ‘off the peg’ transmissions in every way, with A, B, C etc versions of both RT and RTO’s offering differing gear ratios. There were never two versions of the same model gearbox produced with different gate patterns. The gate of the RTO 9 speed was changed to a normal H gate with the introduction of the (overdrive only) ‘New Generation’ RTX in 1981. Although the 11609 version of the RTX gearbox featured better gear meshing which increased its torque capacity, the RT and RTO 11609 versions featured exactly the same design of gears (in the case of the RTO-A vs RTX-A, exactly the same gears), but only the RTX had the linkage inside to cross-over 3rd and 4th gate position with ‘overdrive top’.
We are still rebuilding and modifying these Fuller gearboxes today for use in our own ERF’s, Leyland’s, Foden’s etc with parts now coming direct from the USA and Australia where they are still plentiful. We have a lot of info on them, including the original parts & service manuals and comparison info.
Carryfast:
If I’ve got it right U v H shift pattern denotes RTO v RT ?.While top always remains direct in the case of RT regardless ?.
Don’t think so. At least 2 versions of the direct-top RT seem to have had the ‘U’-shift and ‘H’-shift respectively. Robert
When comparing the two versions of the same gearbox, say the 9509, Carryfast is entirely correct.
If you are comparing the 9509 with a different gearbox, say the 9515, then Robert is correct.
As I said on the other thread about gearboxes, these were standard ‘off the peg’ transmissions in every way, with A, B, C etc versions of both RT and RTO’s offering differing gear ratios. There were never two versions of the same model gearbox produced with different gate patterns. The gate of the RTO 9 speed was changed to a normal H gate with the introduction of the (overdrive only) ‘New Generation’ RTX in 1981. Although the 11609 version of the RTX gearbox featured better gear meshing which increased its torque capacity, the RT and RTO 11609 versions featured exactly the same design of gears (in the case of the RTO-A vs RTX-A, exactly the same gears), but only the RTX had the linkage inside to cross-over 3rd and 4th gate position with ‘overdrive top’.
We are still rebuilding and modifying these Fuller gearboxes today for use in our own ERF’s, Leyland’s, Foden’s etc with parts now coming direct from the USA and Australia where they are still plentiful. We have a lot of info on them, including the original parts & service manuals and comparison info.
Many thanks for coming to the rescue with that excellent clarification, ‘ERF’. I was leading CF up the garden path there, then. Pat Kennett’s 1975 Euro Test description of a modernised RT 9509 'box as an H-shift has misled me into thinking that he actually meant ‘H’-shift: clearly, he really meant H-pattern, not H-shift. That would fit with all the 9-sp Fullers I used from that period, all of which had the U-shift.
What I should be saying, then, is:
The standard fitment was a Fuller RT9509 or RT9509A (slightly different ratios), both of which had an H-pattern gate with a U-pattern shift.
robert1952:
A couple of pages back Eric reminded us that this was pretty normal in the '70s and he mentioned that Scanias at that time Scania’s were geared in Belgium to 90 @ 2100rpm (110 or 140) with 4.71 ratio and no overdrive gearbox. He went on to say that even Volvo with the 8 speed box was reving 2200 @ 90 but all drove at 2400/2500 revs. Robert
It’s probably fair to say that most manufacturers and customers were understandably ignorant of the finer points of gearing a big power ( more importantly big torque ) truck properly in the early 1970’s.However it really wasn’t rocket science by the mid 1970’s as to what was needed and probably no excuses for not understanding that sooner rather than later and thereby getting a head start over the opposition and thereby making far more effective use of the advantages of the turbo ■■■■■■■■■■■■■■■ small cam or big cam the torque characteristics being as close as made no difference in either case.
The comments here,regarding the Scania 141’s revised gearing say it all in that regard.In addition to the well known ‘issues’ regarding the long overdue in getting the gearing right in the case of the ■■■■■■■■
On that note it’s obvious that counting out the use of the RTO Fuller at least in the case of the limited final drive options of the NGC was a stupid move.Which no surprise seems to have been reversed not long after in future models whether Roadranger ‘O’ type.Or the Twin Splitter ‘O’ type even seemingly with Rockwell being more or less ERF’s main axle supplier by that point ?.
As for the NGC they had a perfect opportunity to combine the best aspects of both the 6 cylinder and V8 Scanias ( 6 cylinder simplicity with V8 type torque ) in one truck and effectively blew it in terms of both engine and driveline choice and failure to develop the steel cab model.
Liked that link to the CM archive - very useful! You seem to have moved to a slightly new position here, however. Nobody would deny that the '70s saw a bit of a revolution in the production of drivelines that produced high torque at low revs and gave better and better final drive results. I drove a large range of premium (and not so premium!) tractive units that dated from 1973 onwards, through pretty-well all the stages of that revolution. However, the NGC was conceived very early in the '70s and hit the market in Jan '73. As you say above, there’d have been no excuses for getting it wrong in 1979. But it wasn’t designed in 1979, it was designed in about 1971/2 so it was a product of its time, which does not make it a ‘stupid move’, surely, unless you wish to compare apples with pears. Robert
)
IE as I said we are looking for,at most,1,800 rpm,preferably less ,at ‘either’ 65 mph for UK spec ‘or’ at 90 kmh for Euro spec.The fact that might allow for considerably more road speed ‘if’ the driver chose to run it up to the full 2,100 rpm,in either case,was ( should have been ) irrelevant. 
Bearing in mind that Pat Kennett obviously didn’t have the luxury of an RTO equipped NGC to compare the RT equipped version with in that regard. 
