Hi,
Pondering options to increase the mpg on the motorway. I have a 1965 88 with a Rover 3.5 classic range rover V8 conversion running a standard 4 speed series 2 gearbox. Love it to bits but it sure does drain the tank fast.
Would adding a Fairey Overdrive help? What I know about overdrives can be written on the back of a small stamp with plenty of space to spare. Or is there a better gearbox option?
Thanks
What Mpg do you get with the V8? I get 17-21mpg with standard 2.23. Could have sworn I once got 24mpg on a long gently driven 200mile trip but never repeated.
What diffs have you got bud? The 3.54 rrc diffs make it much less frantic. Still more than enough torque to pull away without looking like a thrash-fest-chav.
I'm a complete anorak when it comes to fuel consumption because I believe it's one of the best ways of telling if you have a start of a problem
with the engine if the consumption starts being affected.
Every time I fill up I brim it and press the trip so that I can keep a record, and when I was without the overdrive for a few weeks recently I
can honestly say it didn't make a jot of difference to the figures.
Mine is behind a 2.25 diesel and I definitely missed it for the difference it made to the noise levels though.
Quote from: nathanglasgow on Apr 27, 2024, 04:29 PMWhat Mpg do you get with the V8? I get 17-21mpg with standard 2.23. Could have sworn I once got 24mpg on a long gently driven 200mile trip but never repeated.
Doing a 120 mile trip I used 6.59g = c.18mpg. However this was a straight run down the A1M doing 50-60 mph with only a 5 min leg either end on B roads. For about half of this I tucked in behind large lorries to get sucked along.
Quote from: cswagon on Apr 27, 2024, 06:04 PMI'm a complete anorak when it comes to fuel consumption because I believe it's one of the best ways of telling if you have a start of a problem
with the engine if the consumption starts being affected.
Every time I fill up I brim it and press the trip so that I can keep a record, and when I was without the overdrive for a few weeks recently I
can honestly say it didn't make a jot of difference to the figures.
Mine is behind a 2.25 diesel and I definitely missed it for the difference it made to the noise levels though.
Nice. I'm a sucker for data. Knowledge is power and all that.
I did check my MPG properly once... I was so horrified that I just stopped thinking about it, now I just treat the petrol station visit as an excuse to have another pasty.
Quote from: Adam1958 on Apr 27, 2024, 04:36 PMWhat diffs have you got bud? The 3.54 rrc diffs make it much less frantic. Still more than enough torque to pull away without looking like a thrash-fest-chav.
It has the 3.54 high ratio Range Rover diffs. LWB steel wheels with 7.50x16 tyres.
Agreed not frantic and a lovely drive with plenty of torque and no issues going up any hills.
That's the other reason not to bother with a Fairey, they were pretty fragile even
when new so wouldn't live for long with a big lump up front.
Quote from: cswagon on Apr 27, 2024, 07:13 PMThat's the other reason not to bother with a Fairey, they were pretty fragile even
when new so wouldn't live for long with a big lump up front.
[/quoteQuote from: cswagon on Apr 27, 2024, 07:13 PMThat's the other reason not to bother with a Fairey, they were pretty fragile even
when new so wouldn't live for long with a big lump up front.
So is a Santana Overdrive more robust than Fairey? I understand they were designed for military vehicles but there does not seem to be a lot of comparison data out there.
A roamerdrive should be able to take the power but expensive to buy direct from Canada
Agreed, if for different reasons. If you stop for a minute - if mpg is hte reason - there's no way fitment of an Overdrive can make sense. Not back in the day, not now. How could it? But then thinking about such things never stopped a purchase decision before. It won't now.
I own a Roverdrive - in the other thread you'll read it's coming out. Only hang on mo' before we consider why, I paid £8-900ish back-when.... these days, or when I last looked, they're £1600+
A decent Fairey is near £900-1000 when I looked.
In 20 odd years I have never ever checked to see if my Roverdrive gives more mpg. Er... why would I? If I ever do, you'd be right to take me outside and shoot me. My fate well deserved. You see, £800-900 for an overdrive then, or whatever it'll cost today, can never be recouped. How can it?
And this on a vehicle in daily use? Even if it gives 5% improvement - which is doubtful - it's in use for 5% of the time. If we're kind, and say 10% and 10% of the time (unlikely) things still won't add up.
Unless you can get a new Roamer or my old Roverdrive for £50. And you can't.
Hence one of the main advantages of an overdrive is to lose money. I knew this BEFORE fitting. Which is why no one has shot me. Yet.
The reason you fit an overdrive is to give your LR longer legs and cut noise. The driving a 'sjgnal-box' thing appeals to me, or did back then. The novelty has long since worn off. A Fairey is fragile, in bad order they're noisy.
So why remove a Roverdrive? I'm removing mine to put a 5-cog box. However take aim, in some quarters this misdeed alone has me best to decide on my last menu.
Without the option of a 5-cog would I fit an overdrive now? Of course, I like them, and no - a 5-cog won't save me money either.
Would an Ashcroft high ratio transfer box (http://www.land-rover.org/fitting-a-high-ratio-transfer-box/) work?
Richard
Should be ok with a V8; because there's more power unlike the2.25.
Quote from: Richard on Apr 27, 2024, 09:22 PMWould an Ashcroft high ratio transfer box (http://www.land-rover.org/fitting-a-high-ratio-transfer-box/) work?
Richard
Great shout and cheaper option. I'll give them a call. Has anyone fitted one?
Quote from: Alan Drover on Apr 27, 2024, 09:40 PMShould be ok with a V8; because there's more power unlike the2.25.
As well as 7.50s and RR diffs?
Quote from: Boxoftricks on Apr 27, 2024, 10:00 PMQuote from: Richard on Apr 27, 2024, 09:22 PMWould an Ashcroft high ratio transfer box (http://www.land-rover.org/fitting-a-high-ratio-transfer-box/) work?
Richard
Great shout and cheaper option. I'll give them a call. Has anyone fitted one?
I have a HRT case fitted on my 200DI series 3 but I understand they are no longer selling them , I beleive it is because they cannot get the new gears manufactured to the same standard as they where getting them made.
Ask them I maybe wrong just forum and internet chats!
Quote from: Boxoftricks on Apr 27, 2024, 10:00 PMQuote from: Richard on Apr 27, 2024, 09:22 PMWould an Ashcroft high ratio transfer box (http://www.land-rover.org/fitting-a-high-ratio-transfer-box/) work?
Richard
Great shout and cheaper option. I'll give them a call. Has anyone fitted one?
In fact it was Diffwhine who suggested it to me when I considered putting in a Roamerdrive for similar reasons (noise and consumption). If this (https://ashcroft-transmissions.co.uk/product/high-ratio-transfer-case-kit/) is the one, and I think it is, it's still on their website.
Richard
If you provide the gear and the casing, they do still seem to offer it. JohnB has one in his 58.
I looked at the Ashcroft solution.Seriously considered it. Ashcroft are not far from me.
It's some £360ish and that's how such things work. Pocket-calculator not required and self-install, it's doubtful it can be done and dusted, all told for £450. Reckon on closer to £500.
For the OP it'll be nicer to drive - ROI is never happening. If we're trying to save money, leave it be.
Yep, fitted one this winter after trying a borrowed 3.54 diff.
I like it, half the cost of an overdrive and without the issues of parts availability, and doesn't affect low ration like diffs.
You send them a bare transfer case, and they re-machine the intermediate gear shaft in a new position. They send it back with a new set of gears to reassemble with.
I went this route based on originality-O/Ds weren't an option in late '58 and I didn't want to put a hole in my one-piece floor. I'm also on 6.00 avons and 45mph was about as quick as you'd want to go. First gear was just about pointless in normal driving.
Cost/spares, as above, I was rebuilding the box anyway so it was out and in pieces. Also no need to replace/calibrate the Speedo.
Proven, using the RR diff for a month or two meant that I knew the std petrol engine could happily manage the 30% ingress in gearing without issues.
I can now trundle around at 45/50 and the whole truck feels so much more relaxed with 55+ easily reached.
For me, it was an easy choice, even with a stock motor. A tdi or v8 would make even more sense with the extra torque to pull away in first.
If anyone wants to try one, I'm near bath.
Jon
Nice to know they are now back in stock.
I have 3.54 diffs, 235 tyres and a Roverdrive behind my 200tdi.
I would suggest that a high ratio transfer box, together with basically the same diff/tyre combination will be too high geared. It'd be like driving around with the overdrive permanently engaged, which would be too much for my setup, definitely.
An overdrive is NOT going to improve your mpg :shakinghead
How you drive it can help ... soft right foot and a stronger throttle return spring might help.
Having the timing setup optimised, fitting electronic ignition will help.
All the engine settings, plugs, points, valve clearances etc.
Remove all unnecessary load weight, tool boxes, spare wheels and roof rack.
No one has mentioned FWHs - they won't help save fuel :shakinghead
(https://www.series2club.co.uk/2023_new_forum/Smileys/wittsends/OD.gif)
Quote from: Serious Series on Apr 28, 2024, 10:58 AMNice to know they are now back in stock.
I think more likely they just build to order.
Quote from: JonB on Apr 28, 2024, 10:35 AMYep, fitted one this winter after trying a borrowed 3.54 diff.
I like it, half the cost of an overdrive and without the issues of parts availability, and doesn't affect low ration like diffs.
You send them a bare transfer case, and they re-machine the intermediate gear shaft in a new position. They send it back with a new set of gears to reassemble with.
I went this route based on originality-O/Ds weren't an option in late '58 and I didn't want to put a hole in my one-piece floor. I'm also on 6.00 avons and 45mph was about as quick as you'd want to go. First gear was just about pointless in normal driving.
Cost/spares, as above, I was rebuilding the box anyway so it was out and in pieces. Also no need to replace/calibrate the Speedo.
Proven, using the RR diff for a month or two meant that I knew the std petrol engine could happily manage the 30% ingress in gearing without issues.
I can now trundle around at 45/50 and the whole truck feels so much more relaxed with 55+ easily reached.
For me, it was an easy choice, even with a stock motor. A tdi or v8 would make even more sense with the extra torque to pull away in first.
If anyone wants to try one, I'm near bath.
Jon
Thanks Jon, having read your review think this is the route for me to take. With the additional power of the V8 don't think over gearing will be an issue. Right now 1st is basically redundant anyway. How long did it take for them to machine it? Thanks
You need to start with a Suffix C or onwards gearbox transfer box casing and you will need the low range gear (36 tooth) from a Suffix C onwards transfer box to make this work (532979).
https://ashcroft-transmissions.co.uk/product/high-ratio-transfer-case-kit/
One point I would emphasise is that building the transfer box properly is essential with this kit. Once its done, its great, but you must follow the WSM set up procedure to the letter.
Hi,
Where is the stamp on the transfer case so I see what suffix I currently have.
Will Ashcroft build up the kit for you or is it DIY?
Quote from: GlenAnderson on Apr 28, 2024, 12:12 PMI have 3.54 diffs, 235 tyres and a Roverdrive behind my 200tdi.
I would suggest that a high ratio transfer box, together with basically the same diff/tyre combination will be too high geared. It'd be like driving around with the overdrive permanently engaged, which would be too much for my setup, definitely.
Save for splitting-hairs (if by different means) you've the same grunt and torque at the same rpm as my set-up. I run 7.50 x 16. I see you've 3:54 & your Roverdrive. That seems like it's going to be too tall. Are you saying you wouldn't add a high-ratio box to your set-up - I'd agree - or, that'd it'd be too tall for the OP? With grunt as ours, I'm thinking we want:
1) Stock + Overdrive
2) Stock + 3.54 (1st a bit high for a 2.25)
3) Stock + HR Transfer (1st a bit high for a 2.25)
4) Stock + 5-cog box.
ie: Overdrive or 3.54, or HR, or 5 cog. Pick any one, not two. Only you appear to have gone for more?
I had a series 3 with a Fairey overdrive for years behind a 3.5 and we later rebuilt the vehicle with a 4.6 Rover V8 and it's still going strong so they are well up to the task if driven sensibly. That vehicle also has 3.5:1 diffs and large tyres and it will cruise quite happily at 60mph
I would try to find a Fairey unit and fit it to give it a go. If you don't like it, take it off and sell it on again, you won't lose money on them.
Craig.
Quote from: Boxoftricks on Apr 28, 2024, 04:17 PMHi,
Where is the stamp on the transfer case so I see what suffix I currently have.
Will Ashcroft build up the kit for you or is it DIY?
The number of the transfer case is the gearbox number although of course there is a risk it may have been swapped in the past. You can't easily tell by just looking at it. You would need to take the bottom cover off and count the teeth on the high range gear. The number is stamped on the side of the gearbox top cover on 2, 2A and early S3 vehicles. After that the number was stamped on the top back of the gearbox casing where it joins the transfer box.
Ashcroft will not build it up. It is a DIY job or find somebody who is OK with setting up a transfer box properly. If you need help and want to do this, let me know. I may be able to assist as you aren't too far away from me I guess.
Quote from: diffwhine on Apr 29, 2024, 10:41 AMQuote from: Boxoftricks on Apr 28, 2024, 04:17 PMHi,
Where is the stamp on the transfer case so I see what suffix I currently have.
Will Ashcroft build up the kit for you or is it DIY?
Thanks for the kind offer. I may well take you up.
The number of the transfer case is the gearbox number although of course there is a risk it may have been swapped in the past. You can't easily tell by just looking at it. You would need to take the bottom cover off and count the teeth on the high range gear. The number is stamped on the side of the gearbox top cover on 2, 2A and early S3 vehicles. After that the number was stamped on the top back of the gearbox casing where it joins the transfer box.
Ashcroft will not build it up. It is a DIY job or find somebody who is OK with setting up a transfer box properly. If you need help and want to do this, let me know. I may be able to assist as you aren't too far away from me I guess.
I've just re-read the thread and to try and condense the various thoughts
Ashcroft need your bare case, I don't think an early small shaft case would matter as they're re-drilling the hole to the bigger size anyway. You would need the later gear as DW has said. It is a diy rebuild, they send back the case and three gears.
My thoughts on usage
2.25 + od = ok
2.25 + 7.50 tyres = ok
2.25 + hrt=ok on 6.00/205 tyres
2.25 + 3.54 diffs = ok on 6.00/205 tyres ( roughly the same change as hrt)
First is not too high for a stock petrol with a hrt on small wheels, using 7.50s might well be though
a v8 with 7.50s and 3.54 diffs might struggle with a hrt added as well. An overdrive or 5 speed would probably be the best way here
Jon
Quote from: NoBeardNoTopKnot on Apr 29, 2024, 08:17 AMQuote from: GlenAnderson on Apr 28, 2024, 12:12 PMI have 3.54 diffs, 235 tyres and a Roverdrive behind my 200tdi.
I would suggest that a high ratio transfer box, together with basically the same diff/tyre combination will be too high geared. It'd be like driving around with the overdrive permanently engaged, which would be too much for my setup, definitely.
Save for splitting-hairs (if by different means) you've the same grunt and torque at the same rpm as my set-up. I run 7.50 x 16. I see you've 3:54 & your Roverdrive. That seems like it's going to be too tall. Are you saying you wouldn't add a high-ratio box to your set-up - I'd agree - or, that'd it'd be too tall for the OP? With grunt as ours, I'm thinking we want:
1) Stock + Overdrive
2) Stock + 3.54 (1st a bit high for a 2.25)
3) Stock + HR Transfer (1st a bit high for a 2.25)
4) Stock + 5-cog box.
ie: Overdrive or 3.54, or HR, or 5 cog. Pick any one, not two. Only you appear to have gone for more?
Yes, I have got "two" upgear setups, plus the bigger tyres. The Tdi (and no doubt the V8) will happily pull both the higher ratio diffs and the overdrive, allowing an easy cruise at 60mph at 2000 rpm (or well north of 80 if you're in a hurry). However, it's the overdrive's flexibility that allows this, because it still gives a relatively low first gear when disengaged. However, that first gear is still high enough that when fully loaded I can find it necessary to use low box for pulling away on a steep hill. Fitting a fixed higher ratio transfer case might be cheaper than an overdrive, but it's a fixed ratio, and as I said I suspect it will make first too high for comfort.
The other issue with higher gearing if you have a 2A gearbox is the need to perfect your double-declutch technique as you'll be doing a lot more shifting in and out of the lower gears.
Thanks Glen. That makes sense, thus it's not so much the tall gearing - and yes, whilst you'll use it... ... more it's the real-world utility 'doubling-up' gives.