Which gearbox?
- Thread starter Hooley
- Start date
Quick update
JDD box is fitted and working!
I am very happy with the results so far, the remapped A2 feels so much more suited to this box than the Polo.
Drivability is great and noise at 70mph is sooo quiet and relaxing….it’s like another car on the motorway.
Did a brim to brim on the way to stealth doing a steady 70mph. 52mpg
Way home with the JDD box fitted (heavier right foot too!). 64mpg
Will post a more detailed account of the JDD gearbox, couple of pics showing rpm in 5th.
JDD box is fitted and working!
I am very happy with the results so far, the remapped A2 feels so much more suited to this box than the Polo.
Drivability is great and noise at 70mph is sooo quiet and relaxing….it’s like another car on the motorway.
Did a brim to brim on the way to stealth doing a steady 70mph. 52mpg
Way home with the JDD box fitted (heavier right foot too!). 64mpg
Will post a more detailed account of the JDD gearbox, couple of pics showing rpm in 5th.
timmus
A2OC Donor
Excellent, Simon! 
The motorway cruising revs are exactly as the maths predict; slightly lower than longer 5th and slightly higher than full 6th. I'm glad that you've seen an immediate return on investment with better motorway economy on your way home.
Dan's already asked the key questions...
Cheers,
Tom
The motorway cruising revs are exactly as the maths predict; slightly lower than longer 5th and slightly higher than full 6th. I'm glad that you've seen an immediate return on investment with better motorway economy on your way home.
Dan's already asked the key questions...
Cheers,
Tom
chubbybrown
Member
This just bolted up to the original flywheel>?
This is a very exciting development and you certainly did put up a strong argument for the installation of this JDD box .... you have stood your ground even with some A2OC members being somewhat negative about its suitability! As you are aware, I have requested, by P.M., the opportunity to feel how your A2 performs on-the-road . I would imagine that there would be quite a few members also wishing to do the very same! I wonder, therefore, if you might have considered allowing a few members to have this chance, but at the same time? I know that, even with any distance involved, I would have liked to have been there! Thank you, Simon
David
David
MikeMarsUK
A2OC Donor
If you make a youtube vid about your JDD gearbox showing shiftpoints & stuff like that I'll link to it from my EuroTuning gearbox vid
(Since the people watching mine would be interested in your solution also).
(Since the people watching mine would be interested in your solution also).
This is so intruiging I've bought a jdd gearbox for my 90 Tdi! It will take me a while to get round to fitting it but I'll post photos of the change when it's done!
Current mods are egr delete pipe (Allard), homemade ecu egr delete and I'm averaging 60mpg with a mix of short and long journeys. On a return trip, Dunkirk-Eindhoven I can get just over 70mpg at steady 65 GPS mph. My goal is 70mpg at 70mph - wonder if its achievable? I'm using 195/65R15's which are grippy enough, very quiet and almost comfortable!
Looking forward to hearing how you're getting on with your new 'box!
Current mods are egr delete pipe (Allard), homemade ecu egr delete and I'm averaging 60mpg with a mix of short and long journeys. On a return trip, Dunkirk-Eindhoven I can get just over 70mpg at steady 65 GPS mph. My goal is 70mpg at 70mph - wonder if its achievable? I'm using 195/65R15's which are grippy enough, very quiet and almost comfortable!
Looking forward to hearing how you're getting on with your new 'box!
timmus
A2OC Donor
Am I right in thinking that the TDI90's gearbox cannot be fitted to a TDI75? If so, then fitting the JDD 'box to a TDI90 could provide a few challenges.
Does the bell housing need to be changed?
A completely standard A2 TDI SE returns 70mpg at 60mph and 60mpg at 70mph, as a crude rule-of-thumb. I reckon you'll get close. My best yet is 78mpg at a true 60mph, but I currently run 205/45/17. It gets increasingly difficult to improve economy at higher speeds though, as aerodynamic drag goes up considerably.
Is this a typo!? 195/65R15 is nearly 7.3% bigger than standard. Eek!
Yes please!
Tom
Last edited:
Was that the £195 box from Norfolk, listed on Ebay? In my usual impulsive way, I'm tempted, myself! I would have liked a test-drive in Simon's, first, though!
David
Apologies, the tyre size was a typo- it's actually 195/60r15's on A3 pepperpots... Originally 205/40r17s and I couldn't stand the harsh ride- felt sorry for the car it thumped so much over bumps!
Yes, it was the one on eBay for £195 - it's arrived fine but a problem with the gearbox casing as its been welded, and quite poorly! Negotiations are now commencing as this wasn't mentioned in the advert!
As far as I can work out it should fit ok as the bluemotion is the same basic engine and even has the variable vane turbo- I wait to be proven wrong though!
I'll keep you posted!
Richard
Yes, it was the one on eBay for £195 - it's arrived fine but a problem with the gearbox casing as its been welded, and quite poorly! Negotiations are now commencing as this wasn't mentioned in the advert!
As far as I can work out it should fit ok as the bluemotion is the same basic engine and even has the variable vane turbo- I wait to be proven wrong though!
I'll keep you posted!
Richard
G
Guest 4123
Guest
On a longish trip e.g. Eastbourne to Gainsborough at mostly 70mph, I usually get an indicated 3.0L/100km or about 95mpg.
RAB
G
Guest 4123
Guest
Actually, on one occasion I managed 2.7 (with the A/C on most of the time) but that was exceptional! Brimming the tank afterwards confirmed that the figures were more or less correct, allowing for the instruments being about +4/5% too optimistic (which will be the same for a 1.4tdi). For more economy from a 1.4tdi, also consider the torque curve, i.e. emulate the 1.2tdi's! Far more important than fiddling around with the underside (possibly).
RAB