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Discussion Starter · #1 ·
In my old escort manual there was a setion which detailed the minimum and maxmium permissable speed for all the gears for all the models. ie 2nd 15 - 60 3rd 20 - 80 etc)

In My R25 manual there is no mention of these statistics.

Does anyone know (even if roughly) what the min/max speed per each gear is for the R25 1.4 103ps model (mine is the 103 ps IL)

Any help appreciated.
 

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imo they wouldnt include it because rovers are thought to be gentlemans cars, not the kind of boy racer hoolagans the ford expected to buy there very successfull rally car.
 

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GreggoTheClown said:
In my old escort manual there was a setion which detailed the minimum and maxmium permissable speed for all the gears for all the models. ie 2nd 15 - 60 3rd 20 - 80 etc)

In My R25 manual there is no mention of these statistics.

Does anyone know (even if roughly) what the min/max speed per each gear is for the R25 1.4 103ps model (mine is the 103 ps IL)

Any help appreciated.
Might be worth looking up an old copy of autocar or something as they often provide ratios for each gear. You could source an old copy or the info might be archived on the net somewhere. I know my copy of autocar about the 400 gave all the final drive ratios and whatnot....worth a shot!
 

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Why not find out by experiment? Take a lower limit of say 1500rpm, and an upper limit of just under the red line. Try it in each gear. Well, maybe not in 4th or fifth...
 

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Discussion Starter · #5 ·
Cheers , ill have a look around.

Dont get me wrong, its not that i want to redline my engine every gear , to be honest its more because I just like to know these things!

Just as a general rule of thumb , what is the minimum revs that the 1.4 can withstand, so it doesnt labour? Is it 1400 like most engines seem to be?
 

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Discussion Starter · #6 ·
Oh, just out of interest , something Ive never really been too sure about, but is it bad for the car to be revved really high, say to about 6 - 7k ?

Or do the engines not "mind" ?
 

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GreggoTheClown said:
Oh, just out of interest , something Ive never really been too sure about, but is it bad for the car to be revved really high, say to about 6 - 7k ?

Or do the engines not "mind" ?
Basically no, the engine has a limiter to prevent you from reaching unsafe engine rotation rates. However, I doubt it does it much good to constantly be spinning incredibly fast, its got to cause more wear in the long run. But I'd still say a car revved properly regularly (not neccessarily till its bouncing off the limiter) will be in better nick than something that gets changed up at 2krpm all the time.
 

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Discussion Starter · #9 ·
Samuel - Thanks for that info, I must admit I had a feeling that was the case, that it would be better for the engine to now and then reach fairly high revs so its doing ts job.

In my R25 i must admit I enjoy revving the car to get to speed - not to boy racer levels, but I usually change up about 3k for the first 3 gears in normal drivng conditions and fuel economy and performance seem good. To get to speed on NSL areas i like to keep 3rd gear for up to 4 - 5k to get to 60, then change straight to 5th.

Ashy - cheers Ill have a look at that and work them out.
 

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Discussion Starter · #10 ·
Well heres what I got

I used two figures frm the table - the mph for 1500rpm and 6000rpm

1st 7.79 - 31.14
2nd 13.67 - 54.65
3rd 19.96 - 79.82
4th 25.24 - 100.95
5th 31.15 - 124.59(!)

The table did have figures for up to 8k revs but I thought in general driving conditions I wouldnt use past 6k, i think maxiumum BHP and torque is about 5 - 6k?
 

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Looks about right, but you could quite easily hit nearly 65mph in second before hitting the limiter and needing to change up. You will still be accelerating faster in that gear then the next one up even though torque will be dropping off.

I regularly take the revs to 6000 rpm. The car just prefers it higher up the range. I usually take the revs up to and beyond 4,000 rpm then change up if I'm on a fast road.
 

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I would say its permissible rpm in each gear is where maximum torque occurs ........its pointless going any further till you reach 4th gear.

don't know what rpm that occurs at because the spec and tech data here isn't working.

all the best..mark
 

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ashy that's great! however the numbers i m getting from the site you suggested seem to be different from those given from the tyre size comparator..that i use..the numbers given from the site for 205/45/17 match the ones from tyre size comparator for 185/60/14 anyway..
could some one please explain what final drive is..!? :)
 

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Final drive or final drive ratio is the ratio between the differential crown wheel and the gearbox output drive pinion. In the example above for the 1.4, the number of teeth on the crown wheel divided by the number of teeth on the gearbox output gear is 3.937.

Greggo, you won't reach 124 mph in 5th as the car hasn't enough power to pull 6000 rpm in top gear.
 

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Discussion Starter · #15 ·
Hence the (!), cause I didnt believe for a second me lil Rover could manage that (unless downhill with the wind behind it)

I suppose the figures are theoretical, and they don't necessarily take the cars power/weight into comparison?

That said Im not keen to go over 70 in this car anyway, flippin' noisey enough at that speed!
 

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GreggoTheClown said:
Hence the (!), cause I didnt believe for a second me lil Rover could manage that (unless downhill with the wind behind it)

I suppose the figures are theoretical, and they don't necessarily take the cars power/weight into comparison?

That said Im not keen to go over 70 in this car anyway, flippin' noisey enough at that speed!
There is some truth in that. Coming down some of the steeper local hills it's like having an extra 30% more power... ;)

Back to your original question. Drive your car and experiment with it noting which low and high engine revs suit each gear under normal driving conditions. The car will inform you of what it likes or does not like....

Experiment between the two extremes:

When wanting best acceleration, no good going beyond max power revs or even torque before changing up... particularly if your car has a rev limiter ... change up sooner ... your car will tell you what's best.

At lower revs, try pulling away smoothly and if your car 'objects' (labouring in gear) select another lower gear and try again using faster engine speeds. As you get to know what is the best technique for your car, you'll get the best out of it be it from faster, slower or economical aspects.

A friend once told me his car goes up a certain steep hill in fifth gear so flexible was his engine. I asked him to demonstrate it and he did. His car did NOT like that treatment. I suggested he quickly select third straight from fifth and floor the pedal which he did. He had no idea his car could go up that hill so fast and smoothly.

Funny old game folks and their cars..;)
 

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Discussion Starter · #17 ·
Thanks MG John

I got the max torque/BHP for my car

Torque 91lb ft/4500 rpm
BHP 102/6000 rpm

Are these rev ranges the optimum for accelating then and beyond it there isnt much power?

Eg if I was going at 50 mph in 5th and wanted to overtake a car in front, would I be best dropping to the gear which is going to giev me these "usuable revs"?
 

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GreggoTheClown said:
Thanks MG John

I got the max torque/BHP for my car

Torque 91lb ft/4500 rpm
BHP 102/6000 rpm

Are these rev ranges the optimum for accelating then and beyond it there isnt much power?

Eg if I was going at 50 mph in 5th and wanted to overtake a car in front, would I be best dropping to the gear which is going to giev me these "usuable revs"?
That is what I would do.... even dropping to second if the car and situation allows....

With those figures you have experiment (safely mind) - take someone with you with a stop watch who knows how to use it.... you may be a little surprised by the findings ...;)
 

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Discussion Starter · #20 ·
Result!

had little experiment the other day driving home from work:-

Thr final part of my journey is along a coast road which is joined by a rounabout. For the first 100 metres of the coast road (just off the rounabout) is a right hand overtaking lane.

I was coming off the roundabout to enter the coastal road and there was a small van in front laden, so I took the right hand lane to overtake. Still in second gear, I floored the gas to see how quickly I could get past the van, which was about 15 metres or so in front and travelling about 30mph+ (but obviosuly starting to pick up speed)

I was pleasantly surprised how quick the car managed to get past - once the revs were 4k( which as per my previous post where maximum torque occurs in my cars engine) and above the car seemed to fly past the van safely and well before the overtaking slip road finished.

I think the lesson ive learned , is to basically not be afraid to rev the engine when needs be, especially in 2nd! In my other car , which was a 1.6 escort, I would stay in 3rd gear when overtaking on that section and sometimes it would be a close call whether Id make it in time past the vehicle in front before the lane ended! Bit hairy!
 
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