240 General: New (to me) 1980 Volvo 244

[loki_the_glt]

Originally Posted by Othen

... and for the next thrilling episode (my winter project) we have: 15" Pholus wheels:

Bob and I had a really nice day out in the RB today - we drove to Worcester to collect a set of nice 15" Pholus wheels for renovation. First the trip: the RB was first class, this was the first longer trip (>30 miles) I'd taken it on, and was really pleased how well it performed. The journey was nearly all motorway and dual carriageway, the RB had no problem keeping up with traffic and cruised at 70 MPH (3750 RPM) most of the way, Bob didn't mind the vinyl cover I'd fitted to the back seat and enjoyed the ride.



On to the wheels: the most important thing is they fit, vice the Virgo wheels:



... very snug indeed.

I've started cleaning them up and they are not too bad:



I'll get the tyres taken off this week. There is a fair bit of surface corrosion to sort out on the backs, but the fronts of three of them are good like this one:



... just one of them is badly scuffed:



On the whole they are a bit better than I'd expected. I've ordered some paint and etch primer, plus some 2 pack alloy putty. I think the wheels will come up just fine and will give me something to do for a while - then I have to decide what to do with them (maybe get some tyres fitted and put them on the RB, maybe have some winters fitted, or perhaps just store them to the day when the RB's Virgo wheels need changing).

All in all Bob and I had a really good day with the RB :-)

Just my tuppence-worth but, the only downside to the Pholus wheels is that they post-date the 240-series cars by several years, being a 940-fit. Obviously the RB is yours to do with as you see fit but the Pholuses (Pholii?) might be seen as going too far as they're not a subtle upgrade like an AW71 gearbox would be.

They do, however, look quite smart; if the Virgos fitted the 940 I would think about swapping wheels between my GLT and the Exxon Valdez when I finally get round to re-commissioning it.

[Laird Scooby]

Originally Posted by loki_the_glt

Just my tuppence-worth but, the only downside to the Pholus wheels is that they post-date the 240-series cars by several years, being a 940-fit. Obviously the RB is yours to do with as you see fit but the Pholuses (Pholii?) might be seen as going too far as they're not a subtle upgrade like an AW71 gearbox would be.

They do, however, look quite smart; if the Virgos fitted the 940 I would think about swapping wheels between my GLT and the Exxon Valdez when I finally get round to re-commissioning it.

I would like to see a photo of the RB with Pholus wheels on one side front and back, it's true what you're saying that they post-date it by some 15 or so years but that isn't always a problem. Often the more modern wheels can still enhance an older body.

Many people have fitted alloy wheels from a post-1980 SD1 to P6 Rovers which really suit it, Jaguar XJ-S wheels ("Starfish" alloys) to earlier Series II XJ cars, Manta GT/E wheels to Mk1 Cavaliers and so on. I suspect the RB would in fact look very good with the Pholus wheels, it's subtly more modern than the Virgo and in my mind, a sort of natural progression.

That said, it's one of those things where it really is a case of beauty is in the eye of the beholder and it's Alans car so his decision must be the final one. Also for those not "in the know", they'll just be another set of nice looking wheels.

[Othen]

Originally Posted by Laird Scooby

The first three ratios are pretty similar on the 4-speed box Alan, 3rd is the same @ 1:1 so there shouldn't be a case of it being less good on economy.

On the 7xx, there is a label on the left hand end of the axle denoting the diff ratio, however over time this label disappears for various reasons. I'm not sure how it's denoted (if at all) on the 2xx so yes, jacking one wheel and counting the turns of the propshaft might be an option. I'd suggest 10 turns of the roadwheel to give you either 35.4 or 37.3 turns of the propshaft as trying to differentiate between 3 1/2 and 3 3/4 turns from one turn of the roadwheel could prove tricky!

Yes, that is a really good idea Dave - aggregating 10 turns of the wheel rather than trying to measure just one (why hadn't I thought of that). I'll have a look around for a tag later on today.

I've been thinking about the gear ratios Dave - yes the first three are similar, so that would be okay. It worries me that top is 44% higher because I don't think the B21a motor makes enough torque to use that without a 3.91:1 rear end. I could just try it and see what happens, but that isn't really my way, I like to plan things and more or less know the outcome.

Fitting a different rear end isn't a huge issue, there will be lots from 740s in scrap yards, but then there are more considerations (like the speedo drive - which one to use). Having found there are at least 3 different types of prop shaft used for 240s back in the day when I was changing the centre bearing, plus a few more for 740s I suspect, that is something to think about as well.

I still think a 4 speeder is a really good aim, I just want to make sure I've thought it all the way through.

Many thanks,

Alan

[Othen]

Originally Posted by loki_the_glt

Just my tuppence-worth but, the only downside to the Pholus wheels is that they post-date the 240-series cars by several years, being a 940-fit. Obviously the RB is yours to do with as you see fit but the Pholuses (Pholii?) might be seen as going too far as they're not a subtle upgrade like an AW71 gearbox would be.

They do, however, look quite smart; if the Virgos fitted the 940 I would think about swapping wheels between my GLT and the Exxon Valdez when I finally get round to re-commissioning it.

Originally Posted by Laird Scooby

I would like to see a photo of the RB with Pholus wheels on one side front and back, it's true what you're saying that they post-date it by some 15 or so years but that isn't always a problem. Often the more modern wheels can still enhance an older body.

Many people have fitted alloy wheels from a post-1980 SD1 to P6 Rovers which really suit it, Jaguar XJ-S wheels ("Starfish" alloys) to earlier Series II XJ cars, Manta GT/E wheels to Mk1 Cavaliers and so on. I suspect the RB would in fact look very good with the Pholus wheels, it's subtly more modern than the Virgo and in my mind, a sort of natural progression.

That said, it's one of those things where it really is a case of beauty is in the eye of the beholder and it's Alans car so his decision must be the final one. Also for those not "in the know", they'll just be another set of nice looking wheels.

Many thanks for your thoughts Loki and Dave,

I'd rather assumed the Pholus wheels were more or less period (ie 1980s), so thank you for letting me know they are a bit more modern. Once I've finished the renovation I'll have a think about what I'm going to do with them. As you know, I have no intention of a renovation on the RB, I've made lots of subtle changes (improvements I hope) already, and I like the idea of a 4 speed gearbox (once I've thought through the engine torque/final drive ratio and a few other issues), so I'm not agin having some non-standard wheels (as I have with the Virgos at the moment).

I'm not going to be able to get a photo of the Pholus wheels on the car until I get some tyres fitted Dave. I made a start on cleaning them up this morn and now they are away to the local F1 Autocentre to have the tyres removed when the fitter has a spare mo.

My initial thoughts (from that first photo above, when I loosely fitted a wheel to make sure the stud pattern and clearance were correct) was that they looked pretty smart and suited the RB. They would be a different direction from the Virgo wheels - less sporty and more saloon. If they come up well I may just put a £150 set of new tyres on and try them for (say) 6 months. Having a spare set of wheels for a car is never a bad thing.

I do so appreciate your views on this; there is no right or wrong answer as to where the RB ends up :-)

Alan

[Laird Scooby]

Originally Posted by Othen

Yes, that is a really good idea Dave - aggregating 10 turns of the wheel rather than trying to measure just one (why hadn't I thought of that). I'll have a look around for a tag later on today.

I've been thinking about the gear ratios Dave - yes the first three are similar, so that would be okay. It worries me that top is 44% higher because I don't think the B21a motor makes enough torque to use that without a 3.91:1 rear end. I could just try it and see what happens, but that isn't really my way, I like to plan things and more or less know the outcome.

Fitting a different rear end isn't a huge issue, there will be lots from 740s in scrap yards, but then there are more considerations (like the speedo drive - which one to use). Having found there are at least 3 different types of prop shaft used for 240s back in the day when I was changing the centre bearing, plus a few more for 740s I suspect, that is something to think about as well.

I still think a 4 speeder is a really good aim, I just want to make sure I've thought it all the way through.

Many thanks,

Alan

I was hoping you'd revisit your maths Alan - 0.69:1 is 31% higher than 1:1, not sure how you arrived at 44%.

The 3.91:1 axle is about 10% lower than the 3.54:1 axle so will equate to ~0.76:1 as the equivalent final drive.

Currently you're getting ~18mph/1000rpm in top/3rd so a 3.91:1 will drop that to ~16mph/1000rpm in 3rd/top. That would be 4375rpm roughly at 70mph in 3rd/top.

With the AW71 in place, it would be ~23mph/1000rpm in 4th/OD or ~3000rpm @ 70mph. Using the presumed 3.54:1 axle and the AW71, it would be ~2700rpm @70mph or ~26mph/1000rpm while retaining 3rd at ~18mph/1000rpm.

Volvo didn't think there would be a problem with the AW71 on the B21A either :

"For the 1983 model year, Volvo dropped the DL and GLE labels, selling the cars simply as 240s. In the domestic Swedish market, the 240 could be had with a 2.1 or 2.3-liter engine (more options were available in export), but the bigger engine always came coupled with a five-speed transmission and tinted windows.[11] The 1983s also received wider side trim and all models had the larger taillights introduced on the previous year's GLT model. A B23E-engined GLE variant was also added (not available with two doors).[11] Buyers protested against the lack of grades and they returned for 1984.[9] A new manual gearbox also arrived for 1984, while a four-speed automatic option was available in the GL. "

Taken from : https://en.wikipedia.org/wiki/Volvo_200_Series

Also thre was an overdrive option on the manual as well - what ratio is used in that?

[Othen]

Originally Posted by Laird Scooby

I was hoping you'd revisit your maths Alan - 0.69:1 is 31% higher than 1:1, not sure how you arrived at 44%.

The 3.91:1 axle is about 10% lower than the 3.54:1 axle so will equate to ~0.76:1 as the equivalent final drive.

Currently you're getting ~18mph/1000rpm in top/3rd so a 3.91:1 will drop that to ~16mph/1000rpm in 3rd/top. That would be 4375rpm roughly at 70mph in 3rd/top.

With the AW71 in place, it would be ~23mph/1000rpm in 4th/OD or ~3000rpm @ 70mph. Using the presumed 3.54:1 axle and the AW71, it would be ~2700rpm @70mph or ~26mph/1000rpm while retaining 3rd at ~18mph/1000rpm.

Volvo didn't think there would be a problem with the AW71 on the B21A either :

"For the 1983 model year, Volvo dropped the DL and GLE labels, selling the cars simply as 240s. In the domestic Swedish market, the 240 could be had with a 2.1 or 2.3-liter engine (more options were available in export), but the bigger engine always came coupled with a five-speed transmission and tinted windows.[11] The 1983s also received wider side trim and all models had the larger taillights introduced on the previous year's GLT model. A B23E-engined GLE variant was also added (not available with two doors).[11] Buyers protested against the lack of grades and they returned for 1984.[9] A new manual gearbox also arrived for 1984, while a four-speed automatic option was available in the GL. "

Taken from : https://en.wikipedia.org/wiki/Volvo_200_Series

Also thre was an overdrive option on the manual as well - what ratio is used in that?

Hi Dave,

The maths: 1.00/0.69 = 1.44 (hence 44% higher); so for every revolution of a AW71 output shaft the BW55 turns 1.44 times. The other way of looking at it is for every revolution of the BW55's output shaft the AW71 turns 0.69 times (31% lower). Mathematically both are perfectly true of course, it is just a manifestation of which number one is taking a percentage of (as Disraeli said: there are lies, damn lies and statistics :-)).

If I leave the back axle as it is then at 70 MPH 3750 RPM (BW55 box) becomes 2587 RPM (AW71 box) - (not that it matters a jot, but 3750 is 44% greater than 2587) - my concern is that the B21a motor (my B21a motor, the 40 year old one that only had 100 HP when new) will not generate enough power (power being the product or torque and speed) at 2600 RPM, the result would be the transmission would keep changing down to third (at about 3750 RPM).

My feeling is that I would have to change the rear end to a 3.91:1 ratio, and so lower the gearing to 3.54/3.91=0.905 (as you say, about 10% lower). The overall gearing would then change from 1.0*3.54=3.54:1 to 0.69*3.91=2.7:1; consequently one might expect 70MPH to equate to 3750*2.7/3.54=2860 RPM (this would be for a AW71 gearbox with a 3.91:1 rear end).

That seems much more realistic to me, and I suspect is what Volvo used for the post 1984 240s fitted with a AW71 gearbox, and is probably the set up used for 740s (which seems to accord with what John said above: 2.3 FI autos, turned over at an indicated 2,700 RPM at 60 MPH (a needle's width over 3000 at 70)). I don't know this yet, it is what I have to find out and decide upon between now and April.

So, at 70 MPH we should have:

BW55+3.54:1 final drive: 3750 RPM.
AW71+3.54:1 final drive: 2600 RPM.
AW71+3.91:1 final drive: 2860 RPM.

... my gut feeling is that the B21a will not produce enough power at 2600 RPM to make the middle set up work, but it might well at 2860 RPM. I don't know the answer to this one yet :-) Probably the best way of finding out would be to find out the final drive ratio of a post 1984 car fitted with a AW71 gearbox and a B21a motor (I'm guessing from the above that Volvo still used the B21a in the post-1984 cars).

This has been a really useful exercise. I'll be most happy to be wrong about my theory that a B21a will not manage a 4 speed gearbox with a 3.54:1 final drive.

Many thanks Dave,

Alan

[Laird Scooby]

Originally Posted by Othen

Hi Dave,

The maths: 1.00/0.69 = 1.44 (hence 44% higher); so for every revolution of a AW71 output shaft the BW55 turns 1.44 times. The other way of looking at it is for every revolution of the BW55's output shaft the AW71 turns 0.69 times (31% lower). Mathematically both are perfectly true of course, it is just a manifestation of which number one is taking a percentage of (as Disraeli said: there are lies, damn lies and statistics :-)).

If I leave the back axle as it is then at 70 MPH 3750 RPM (BW55 box) becomes 2587 RPM (AW71 box) - (not that it matters a jot, but 3750 is 44% greater than 2587) - my concern is that the B21a motor (my B21a motor, the 40 year old one that only had 100 HP when new) will not generate enough power (power being the product or torque and speed) at 2600 RPM, the result would be the transmission would keep changing down to third (at about 3750 RPM).

My feeling is that I would have to change the rear end to a 3.91:1 ratio, and so lower the gearing to 3.54/3.91=0.905 (as you say, about 10% lower). The overall gearing would then change from 1.0*3.54=3.54:1 to 0.69*3.91=2.7:1; consequently one might expect 70MPH to equate to 3750*2.7/3.54=2860 RPM (this would be for a AW71 gearbox with a 3.91:1 rear end).

That seems much more realistic to me, and I suspect is what Volvo used for the post 1984 240s fitted with a AW71 gearbox, and is probably the set up used for 740s (which seems to accord with what John said above: 2.3 FI autos, turned over at an indicated 2,700 RPM at 60 MPH (a needle's width over 3000 at 70)). I don't know this yet, it is what I have to find out and decide upon between now and April.

So, at 70 MPH we should have:

BW55+3.54:1 final drive: 3750 RPM.
AW71+3.54:1 final drive: 2600 RPM.
AW71+3.91:1 final drive: 2860 RPM.

... my gut feeling is that the B21a will not produce enough power at 2600 RPM to make the middle set up work, but it might well at 2860 RPM. I don't know the answer to this one yet :-) Probably the best way of finding out would be to find out the final drive ration of a post 1984 car fitted with a AW71 gearbox and a B21a motor (I'm guessing from the above that Volvo still used the B21a in the post-1984 cars).

This has been a really useful exercise. I'll be most happy to be wrong about my theory that a B21a will not manage a 4 speed gearbox with a 3.54:1 final drive.

Many thanks Dave,

Alan

Ah, i get the 44% now! Researching the B21A on 1985 on models with the AW71 and/or the M46 gearbox would be helpful as you'd then know what ratio the back axle was on the auto and if you researched the M46, the manual with overdrive.

I think yours was 106bhp when new so should still be capable of at least 100bhp but it's the torque curve you really need to know. If you have as much torque at 2800rpm as 3800 or very nearly, you shouldn't need to change the back axle ratio. This will provide some interesting reading for you, particularly the axle ratios (Volvo used both 3.73:1 and 3.54:1 on the B21A with AW71 box and the change up point into 4th is ~70-72mph in both cases) :

http://www.myvolvolibrary.info/Tech_...W71_Part-1.pdf

Note that is for MY75 so will easily apply to yours as well!

[Othen]

Originally Posted by Laird Scooby

Ah, i get the 44% now! Researching the B21A on 1985 on models with the AW71 and/or the M46 gearbox would be helpful as you'd then know what ratio the back axle was on the auto and if you researched the M46, the manual with overdrive.

I think yours was 106bhp when new so should still be capable of at least 100bhp but it's the torque curve you really need to know. If you have as much torque at 2800rpm as 3800 or very nearly, you shouldn't need to change the back axle ratio. This will provide some interesting reading for you, particularly the axle ratios (Volvo used both 3.73:1 and 3.54:1 on the B21A with AW71 box and the change up point into 4th is ~70-72mph in both cases) :

http://www.myvolvolibrary.info/Tech_...W71_Part-1.pdf

Note that is for MY75 so will easily apply to yours as well!

Thank you again Dave,

I'm getting my head around this problem now. I agree entirely with your assessment that the torque output for a B21a at 2600 RPM is the critical thing - so there would be no point me increasing the power if this required the engine to run at higher revs to achieve that. The BofH lists my engine as 100 HP @5250 RPM and maximum torque as 125 lbf.ft @3000 RPM, which tells us much more. My gut feeling (and it is that, I have no means of measuring it) is that the motor will not be producing enough torque at 2600RPM for the gearbox to stay in top (I had a Mazda with an auto box about 25 years ago that could not quite decide which gear it wanted to be in at 60 MPH and would irritatingly chop and change).

To an extent my feelings are corroborated by John's comment above on his 740, which (if my memory is correct) was a 2.3 litre FI model (and so one might expect more torque) that pulled 3000 RPM at 70 MPH. That sounds reasonable to me, I've just googled the 740 (not sure if it is the same model: maximum power of 116 PS (114 bhp - 85 kW) at 5400 rpm and a maximum torque of 183 Nm (134 lb. ft) at 2500 rpm, so about 10% more torque, but more critically 500RPM lower. My guess (from my last) is that John's 740 has either a 3.91:1 or 4.1:1 rear axle (but certainly not 3.54:1).

The green book link you sent is almost the same as mine (which is a 1989 edition), and where I found the internal ratios I used above. What I can't find in it is the final drive ratios for the 240 (unless I missed it), so I'm wondering where the bit about 'Volvo using 3.73:1 and 3.54:1 on the B21A with AW71 box' came from? I think that is probably key to the whole thing. The only reference to final drive ratios for the AW71 are 3.73:1 and 3.91:1 (on pp9 under governor pressures, but that doesn't say what model has which ratio). I can't find anywhere that says the AW71 works with a B21a motor and a 3.54:1 final drive (but your eyes may be sharper than mine are Dave).

This is a really useful discussion and I'm making considerable progress. I'm still far from convinced that my B21a's torque characteristics would make a AW71 box suitable without a 3.91:1 or 4.1:1 final drive - but I would be absolutely delighted to be proven wrong. This is exactly why I'm going through this process now - I don't want to find out when I test drive the RB with a AW71 box in May next year :-)

Many thanks again Dave - this is really thought provoking.

Alan

PS. Whilst out walking Bob this afternoon I thought about changing the final drive - it would make it a rather bigger and more complex job, but moving to a 3.91:1 with a Aw71 box would mean that 1st, 2nd and 3rd would each be about 10% lower than they are now - so the rather sluggish acceleration would become considerably brisker, but at the same time top gear would be something like 25% higher (the percentages are really rough here, I haven't worked anything out). It is a lot more work and expense, but my feeling is it will be required to make this work with a 100 HP motor. What do you think?

[Laird Scooby]

Originally Posted by Othen

What I can't find in it is the final drive ratios for the 240 (unless I missed it), so I'm wondering where the bit about 'Volvo using 3.73:1 and 3.54:1 on the B21A with AW71 box' came from? I think that is probably key to the whole thing. The only reference to final drive ratios for the AW71 are 3.73 and 3.91 (on pp9 under governor pressures, but that doesn't say what model has which ratio). I can't find anywhere that says the AW71 works with a B21a motor and a 3.54:1 final drive

Alan

It's just under the gear ratios about 5 pages in Alan. I haven't got the facility to copy from the pdf reader unless i reboot and use Windoze which takes about 2 hours to get working because it downloads a shedload of updates!

[Laird Scooby]

My apologies Alan, i was looking at the BW55 but further down, it shows the B21F engine had the AW71. This was a low compression, catalysed, USA emissions strangled spec engine that gave less power and torque than yours does (something like 93bhp) and lists the same axle ratios as i suggested.