Gearbox Advice For Taller Gearing Please?
Moderators: User administrators, Moderators
-
- Registered user
- Posts: 108
- Joined: 14 Dec 2013, 00:35
- 80-90 Mem No: 0
- Location: Hastings, East Sussex
Gearbox Advice For Taller Gearing Please?
Hi all. I’d really appreciate some gearbox advice please?
I have an ’88 Autosleeper hightop which was originally a 1.9 but has recently had a recon 2.1DJ from the VW Engine Centre. Even though it’s still on the 1.9’s Pierburg there’s been a noticeable increase in torque/power and now it feels like it could really benefit from taller gearing.
I have been offered an AAP 5 speed box which has just come out of a 2.1 and according to the seller is in good working order (only being taken out to install a more modern engine & box).
There’s nothing mechanically wrong with my current 4 speed box (as far as I can tell as a layman) but it is of course it’s 35 years old and has done over 150k miles (presuming it’s the original ‘box which I believe it is).
(UPDATE) I'm assuming my current 4 speed final drive ratio is 4.83 (will check code asap) and therefore the AAP's 4.57 is about 10% difference.
So now I’m note sure whether to:
1) Have the 5 speed AAP box reconditioned and fitted?
2) Have the AAP box fitted as it is and hope it’s ok (and if it’s not, then have it reconditioned)?
3) Have a 4 speed reconditioned box fitted, using the parts required from the AAP for taller gearing?
4) Just stick with the current 4 speed box as maybe the slightly taller gearing from the AAP just isn’t worth the hassle / expense?
5) Something else I haven’t thought of?
Any thoughts would be much appreciated, TIA
I have an ’88 Autosleeper hightop which was originally a 1.9 but has recently had a recon 2.1DJ from the VW Engine Centre. Even though it’s still on the 1.9’s Pierburg there’s been a noticeable increase in torque/power and now it feels like it could really benefit from taller gearing.
I have been offered an AAP 5 speed box which has just come out of a 2.1 and according to the seller is in good working order (only being taken out to install a more modern engine & box).
There’s nothing mechanically wrong with my current 4 speed box (as far as I can tell as a layman) but it is of course it’s 35 years old and has done over 150k miles (presuming it’s the original ‘box which I believe it is).
(UPDATE) I'm assuming my current 4 speed final drive ratio is 4.83 (will check code asap) and therefore the AAP's 4.57 is about 10% difference.
So now I’m note sure whether to:
1) Have the 5 speed AAP box reconditioned and fitted?
2) Have the AAP box fitted as it is and hope it’s ok (and if it’s not, then have it reconditioned)?
3) Have a 4 speed reconditioned box fitted, using the parts required from the AAP for taller gearing?
4) Just stick with the current 4 speed box as maybe the slightly taller gearing from the AAP just isn’t worth the hassle / expense?
5) Something else I haven’t thought of?
Any thoughts would be much appreciated, TIA
Last edited by triumph2.5pi on 19 Jun 2022, 06:23, edited 1 time in total.
1988 Autosleeper High Top
2.1DJ (Pierburg carb)
AAP 5 Speed, 711 Shifter
2.1DJ (Pierburg carb)
AAP 5 Speed, 711 Shifter
- T3luestar
- Registered user
- Posts: 622
- Joined: 07 May 2012, 10:31
- 80-90 Mem No: 13845
- Location: Widnes
Re: Gearbox Advice For Taller Gearing Please?
Get the code of your 4 speed and compare the ratios with the 5 speed, you might not actually gain anything by swapping boxes and gear linkage etc.
https://rjes.com/html/gearbox_types.html
https://rjes.com/html/gearbox_types.html
Gearbox Advice For Taller Gearing Please?
As above. Not a lot of differences
-
- Registered user
- Posts: 108
- Joined: 14 Dec 2013, 00:35
- 80-90 Mem No: 0
- Location: Hastings, East Sussex
Re: Gearbox Advice For Taller Gearing Please?
Thanks. I had just assumed my current 4 speed final drive was 4.83, but I don't know that for certain so will check the code on the box.
If it is, I'm aware changing for a 4.57 isn't a huge difference, but a roughly 10% or 350rpm drop at 70mph to me would be "worth it" I think?
If it is, I'm aware changing for a 4.57 isn't a huge difference, but a roughly 10% or 350rpm drop at 70mph to me would be "worth it" I think?
1988 Autosleeper High Top
2.1DJ (Pierburg carb)
AAP 5 Speed, 711 Shifter
2.1DJ (Pierburg carb)
AAP 5 Speed, 711 Shifter
- Aidan
- Trader
- Posts: 6557
- Joined: 11 Oct 2005, 19:21
- 80-90 Mem No: 742
- Location: Llanfyllin, mid Wales : )
- Contact:
Re: Gearbox Advice For Taller Gearing Please?
roughly a 8.8% difference in top gear between ABD 4 speed and AAP 5 Speed, 3600rpm becomes 3280rpm
I have a refurbished rhd 5 speed gearstick and box under and front linkage in stock if you go that way; you can use the 4 speed stick and linkage set up but you'd drive it like a Syncro, under the gate and back to get 1st, some can cope with it, some don't like it, many just pull away in 2nd all the time and treat it like a 4 speed but the 2nd gear is too high really to use as a 1st and you will put extra wear on 2nd gear and the mainshaft or you'll be slipping the clutch a little to get moving
I have a refurbished rhd 5 speed gearstick and box under and front linkage in stock if you go that way; you can use the 4 speed stick and linkage set up but you'd drive it like a Syncro, under the gate and back to get 1st, some can cope with it, some don't like it, many just pull away in 2nd all the time and treat it like a 4 speed but the 2nd gear is too high really to use as a 1st and you will put extra wear on 2nd gear and the mainshaft or you'll be slipping the clutch a little to get moving
-
- Registered user
- Posts: 108
- Joined: 14 Dec 2013, 00:35
- 80-90 Mem No: 0
- Location: Hastings, East Sussex
Re: Gearbox Advice For Taller Gearing Please?
Thank you. I'll bear your gearstick & linkage in mind. Would the original 1.9 '88 Autosleeper box definitely be ABD do you know?Aidan wrote: ↑19 Jun 2022, 07:35 roughly a 8.8% difference in top gear between ABD 4 speed and AAP 5 Speed, 3600rpm becomes 3280rpm
I have a refurbished rhd 5 speed gearstick and box under and front linkage in stock if you go that way; you can use the 4 speed stick and linkage set up but you'd drive it like a Syncro, under the gate and back to get 1st, some can cope with it, some don't like it, many just pull away in 2nd all the time and treat it like a 4 speed but the 2nd gear is too high really to use as a 1st and you will put extra wear on 2nd gear and the mainshaft or you'll be slipping the clutch a little to get moving
1988 Autosleeper High Top
2.1DJ (Pierburg carb)
AAP 5 Speed, 711 Shifter
2.1DJ (Pierburg carb)
AAP 5 Speed, 711 Shifter
-
- Registered user
- Posts: 1911
- Joined: 10 Aug 2019, 23:30
- 80-90 Mem No: 17004
- Location: Coventry
Re: Gearbox Advice For Taller Gearing Please?
Crikey, 3280rpm sounds better than 4000+ for my 5 speed
1985 LeisureDrive 2.1DJ 5 Speed syncro conversion project.
1979 LT 2.0CH Westy project
1979 LT 2.0CH Westy project
- Aidan
- Trader
- Posts: 6557
- Joined: 11 Oct 2005, 19:21
- 80-90 Mem No: 742
- Location: Llanfyllin, mid Wales : )
- Contact:
Re: Gearbox Advice For Taller Gearing Please?
Most 4 speed 1.9 petrols had ABD in 1988, a few had ABB which is 4.57 final drive with the 0.85 4th gear, only way to tell is check the box itself
Gearbox Codes - VW-T25-T3-Vanagon-Bus-custom- Gearbox- Vantopia
Gearbox Codes - VW-T25-T3-Vanagon-Bus-custom- Gearbox- Vantopia
Re: Gearbox Advice For Taller Gearing Please?
Not wishing to hi-jack, but just my two pence worth ( as someone who hasn't had a 4sp ) is that my ABN or ABM ( can't remember which ) is great between the gears when moving, but not for first gear pulling away.
I find 1st too low and almost pointless, awkward to get into, but 2nd is too high to pull away in without slipping the clutch - which I don't like doing.
I think what I am trying to say is I sometimes wonder whether I'd sacrifice higher revs at motorway speed for better drivability around town at low speed. Given the option for a 4sp with good final drive, I may do that if I ever need to swap my gearbox out.
I find 1st too low and almost pointless, awkward to get into, but 2nd is too high to pull away in without slipping the clutch - which I don't like doing.
I think what I am trying to say is I sometimes wonder whether I'd sacrifice higher revs at motorway speed for better drivability around town at low speed. Given the option for a 4sp with good final drive, I may do that if I ever need to swap my gearbox out.
'89 1.9 DG
“It's Easier to Fool People Than It Is to Convince Them That They Have Been Fooled.” ~ Mark Twain.
“It's Easier to Fool People Than It Is to Convince Them That They Have Been Fooled.” ~ Mark Twain.
-
- Registered user
- Posts: 108
- Joined: 14 Dec 2013, 00:35
- 80-90 Mem No: 0
- Location: Hastings, East Sussex
Re: Gearbox Advice For Taller Gearing Please?
Aidan wrote: ↑19 Jun 2022, 07:35 roughly a 8.8% difference in top gear between ABD 4 speed and AAP 5 Speed, 3600rpm becomes 3280rpm
I have a refurbished rhd 5 speed gearstick and box under and front linkage in stock if you go that way; you can use the 4 speed stick and linkage set up but you'd drive it like a Syncro, under the gate and back to get 1st, some can cope with it, some don't like it, many just pull away in 2nd all the time and treat it like a 4 speed but the 2nd gear is too high really to use as a 1st and you will put extra wear on 2nd gear and the mainshaft or you'll be slipping the clutch a little to get moving
I've sent you a pm Aidan
1988 Autosleeper High Top
2.1DJ (Pierburg carb)
AAP 5 Speed, 711 Shifter
2.1DJ (Pierburg carb)
AAP 5 Speed, 711 Shifter
-
- Registered user
- Posts: 193
- Joined: 06 Sep 2020, 06:40
- 80-90 Mem No: 0
Re: Gearbox Advice For Taller Gearing Please?
An easily reversable option would be larger wheels. Either tyres, or rims and tyres. My speedo over reads by around 5%, so an increase tyre circumference of 5% will both correct the speedo and drop the revs 5%.
1982 Holdsworth poptop. 2L CU Aircooled.
1982 Danbury tintop Caravelle. 2L CU Aircooled.
1982 Danbury tintop Caravelle. 2L CU Aircooled.
- mrhutch
- Registered user
- Posts: 1111
- Joined: 09 Jun 2006, 09:27
- 80-90 Mem No: 2698
- Location: Herefordshire & all over
Re: Gearbox Advice For Taller Gearing Please?
Rosie n' Jim wrote: ↑19 Jun 2022, 18:53 An easily reversable option would be larger wheels. Either tyres, or rims and tyres. My speedo over reads by around 5%, so an increase tyre circumference of 5% will both correct the speedo and drop the revs 5%.
I'd agree with this..
I spent a few months with a bus playing with gear ratios etc.. my advice would be to make a choice that gives you acceptable revs for the work being done...
At the time (a good few years ago) I was regularly driving to the south coast or north yorks for work - each trip was at least 200 miles in one sitting..
so I got a setup that suited, IIRC it was 16" wheels with tall tyres and an Aircooled (DK) box - 4 speed with high fourth - running off a 2.0 gti engne
Motorways were lovely, cruise at 65 - 70 at about 3500 rpm (maybe a bit more, this was back in the times where everyone was going TDi)
country/a road driving was awful...
1981 Vanagon Westy Burning oil as fuel...