Overdrive set up please!

WPR678B · Oct 25th, 2011, 16:38

I have covered a few thousand miles now in my 145 that i got back on the road earlier this year (as posted in this thread : http://www.volvoforums.org.uk/showthread.php?t=97031 ) and i would really like to fit the overdrive set up to it now!
I want to be able to keep the long stick and i understand that the gearbox will also need to be changed to one that will accept the overdrive unit? along with the propshaft and crossmember.
Could anyone help me out with the parts required to do the conversion please? I will need a full set up!
I intend to keep the car for many years to come so feel this is the right way to go rather than chopping it about to fit a different/later box!
I am based near Bournemouth but can travel a bit to collect... Many thanks in advance!

eternal optimist · Oct 29th, 2011, 09:05

What you're looking to do can be done - I did the same to my 1969 145S about 12-13 years ago, keeping the long gearstick. It's the M41 gearbox and J type overdrive if I remember correctly - the Amazon's D type can be used, can't temember what the difference is - I think the J type has taller gearing than the D type.

At the same time I changed to a saloon rear axle to improve the gearing. I was doing about 25,000 miles/year with regular trips to Belgium and wanted to be able to hear myself think.

kean · Feb 16th, 2012, 19:30

Hello Eternal Optimist,
Do you know (or anyone else out there) how inter-changeable a D-type to J-type might be?
Did you run J-type andsaloon diff on your 145?
Are the ratios in the 'boxes themselves the same between M40 and M41?
Is a p1800 'box compatible with a 145?

Sorry, lots of questions - any answers or advice gratefully received!
Kean

eternal optimist · Feb 16th, 2012, 20:52

Blimey, I used to know all of that - I've forgotten almost everything I knew. I did go for the J type OD and the saloon axle - wanted to get the revs down as much as I could within reason. Most of my driving was motorway.

I'd talk to Tony Barrett, or Rob Henchoz (not sure I've spelt his name right). I used to use Charlie Garrett in Oxford, but he's given up Volvo's and sells old Japanese motorbikes these days.

How old is your 145?

classicswede · Feb 16th, 2012, 21:23

The M40 and M41 ratios are the same.
You can use a P1800 box but will need the 140 remote. The 4 speed remote fits.

If you want ultamte high ratio a 164 diff would be the one to use.

kean · Feb 17th, 2012, 19:29

Many thanks for your prompt and most useful responses.
P1800 box then and my M40 remote should fit the bill.
The car is a 1972 model, three piece grille, low indicators.

What's the difference between J-type and D-type? I understand J-type is 0.75 overdrive.

I think that I'll stick with current diff for gradeability reasons at the moment over pure hypermiling economy, but thanks for the good tip regarding 164 diff!

Derek UK · Feb 17th, 2012, 20:26

If the M41 originally came with a D type OD the J type isn't compatible. Vice versa is also true.

eternal optimist · Feb 17th, 2012, 20:34

Quote:

Originally Posted by kean

What's the difference between J-type and D-type? I understand J-type is 0.75 overdrive.

I think the D type is 0.83

Oct 25th, 2011, 16:38	#1
WPR678B Ex 145 owner Last Online: Oct 28th, 2023 16:26 Join Date: May 2007 Location: Dorset	Overdrive set up please! I have covered a few thousand miles now in my 145 that i got back on the road earlier this year (as posted in this thread : http://www.volvoforums.org.uk/showthread.php?t=97031 ) and i would really like to fit the overdrive set up to it now! I want to be able to keep the long stick and i understand that the gearbox will also need to be changed to one that will accept the overdrive unit? along with the propshaft and crossmember. Could anyone help me out with the parts required to do the conversion please? I will need a full set up! I intend to keep the car for many years to come so feel this is the right way to go rather than chopping it about to fit a different/later box! I am based near Bournemouth but can travel a bit to collect... Many thanks in advance! __________________

Feb 16th, 2012, 21:23	#5
classicswede Trader Volvo in my veins Last Online: Yesterday 23:53 Join Date: Dec 2004 Location: Anglesey	The M40 and M41 ratios are the same. You can use a P1800 box but will need the 140 remote. The 4 speed remote fits. If you want ultamte high ratio a 164 diff would be the one to use. __________________ http://www.classicswede.org www.classicswede.co.uk

Oct 29th, 2011, 09:05	#2
eternal optimist Master Member Last Online: Apr 22nd, 2024 16:19 Join Date: Nov 2006 Location: Reading	What you're looking to do can be done - I did the same to my 1969 145S about 12-13 years ago, keeping the long gearstick. It's the M41 gearbox and J type overdrive if I remember correctly - the Amazon's D type can be used, can't temember what the difference is - I think the J type has taller gearing than the D type. At the same time I changed to a saloon rear axle to improve the gearing. I was doing about 25,000 miles/year with regular trips to Belgium and wanted to be able to hear myself think.

Feb 16th, 2012, 19:30	#3
kean Junior Member Last Online: Feb 22nd, 2017 21:14 Join Date: Dec 2008 Location: Solihull	Hello Eternal Optimist, Do you know (or anyone else out there) how inter-changeable a D-type to J-type might be? Did you run J-type andsaloon diff on your 145? Are the ratios in the 'boxes themselves the same between M40 and M41? Is a p1800 'box compatible with a 145? Sorry, lots of questions - any answers or advice gratefully received! Kean

Feb 16th, 2012, 20:52	#4
eternal optimist Master Member Last Online: Apr 22nd, 2024 16:19 Join Date: Nov 2006 Location: Reading	Blimey, I used to know all of that - I've forgotten almost everything I knew. I did go for the J type OD and the saloon axle - wanted to get the revs down as much as I could within reason. Most of my driving was motorway. I'd talk to Tony Barrett, or Rob Henchoz (not sure I've spelt his name right). I used to use Charlie Garrett in Oxford, but he's given up Volvo's and sells old Japanese motorbikes these days. How old is your 145?

Feb 17th, 2012, 19:29	#6
kean Junior Member Last Online: Feb 22nd, 2017 21:14 Join Date: Dec 2008 Location: Solihull	Many thanks for your prompt and most useful responses. P1800 box then and my M40 remote should fit the bill. The car is a 1972 model, three piece grille, low indicators. What's the difference between J-type and D-type? I understand J-type is 0.75 overdrive. I think that I'll stick with current diff for gradeability reasons at the moment over pure hypermiling economy, but thanks for the good tip regarding 164 diff!

Feb 17th, 2012, 20:26	#7
Derek UK VOC Member Last Online: Yesterday 14:29 Join Date: Jul 2006 Location: Chatham	If the M41 originally came with a D type OD the J type isn't compatible. Vice versa is also true.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)