AAZ to AHU conversion
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AAZ to AHU conversion
Hi all, not trying to go over old ground here but I've read heaps and heaps of info and I think I'm suffering from overload! I've read a lot about converting from standard to both AAZ and 1Z/AHU but can't find much on upgrading from one to the other, I think I will have about a million questions but let's start off with a couple that should be quite easy! -
I'm planning, for now, to use the gearbox that's in there, will it already have the correct input shaft fitted from when the AAZ install was done?
I think, to get it on the road quicker I'm going to start off using a Land Rover injection pump, I understand the pump mount has to be modified for this, is it still possible to fit the TDI pump once this has been done?
I'm planning, for now, to use the gearbox that's in there, will it already have the correct input shaft fitted from when the AAZ install was done?
I think, to get it on the road quicker I'm going to start off using a Land Rover injection pump, I understand the pump mount has to be modified for this, is it still possible to fit the TDI pump once this has been done?
- ZsZ
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Re: AAZ to AHU conversion
I m not very familiar with the rover pump, but I think it is bolt on on the AFN, but you have to enlarge the mount hole on a 1Z/AHU. You can change the mount back to a factory one when you go on e-tdi later.
If you go on the mtdi route, you can use the intake and exhaust manifold and turbo from your existing AAZ setup they are probably from the JX. Changing from AAZ is almost similar to changing from JX except small things like the flywheel. The easiest mtdi swaps are using 1Z transverse mount engines.
If you want to use the tdi flywheel, tdi clutch with tdi friction plate then you will need the input shaft with modified splines. This is essential when you want dual mass flywheel. Or you can use a single mass tdi flywheel with a 2.1 petrol T25 friction plate, then you don't need the input shaft. Or you can use the AAZ flywheel and clutch (or even the JX one if it was not changed to the thicker AAZ before) but in this case aramid fiber reinforced friction plates are recommended.
JX has slim flywheel with 210mm diam. friction plate. AAZ has thick flywheel with 210mm diam. friction plate. TDI has thick flywheel (or thick dual mass flywheel) with 228mm diam. friction plate.
If you go on the mtdi route, you can use the intake and exhaust manifold and turbo from your existing AAZ setup they are probably from the JX. Changing from AAZ is almost similar to changing from JX except small things like the flywheel. The easiest mtdi swaps are using 1Z transverse mount engines.
If you want to use the tdi flywheel, tdi clutch with tdi friction plate then you will need the input shaft with modified splines. This is essential when you want dual mass flywheel. Or you can use a single mass tdi flywheel with a 2.1 petrol T25 friction plate, then you don't need the input shaft. Or you can use the AAZ flywheel and clutch (or even the JX one if it was not changed to the thicker AAZ before) but in this case aramid fiber reinforced friction plates are recommended.
JX has slim flywheel with 210mm diam. friction plate. AAZ has thick flywheel with 210mm diam. friction plate. TDI has thick flywheel (or thick dual mass flywheel) with 228mm diam. friction plate.
Zoltan
1986 Multivan ex-Caravelle. Van since 2006, running mTDi 1Z since 2008 with Fiat Croma 1.9 TDid pump 2008-2019, custom pump since 2019
5spd custom box 4.57 diff + 0.74 5th
1986 Multivan ex-Caravelle. Van since 2006, running mTDi 1Z since 2008 with Fiat Croma 1.9 TDid pump 2008-2019, custom pump since 2019
5spd custom box 4.57 diff + 0.74 5th
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Re: AAZ to AHU conversion
Thanks, that all helps and makes things a little clearer. I already have my AHU engine, it's currently sitting in a Golf (bought from a member here) so is a transverse one. Both my van and my Golf are sat at a restorers at the moment, they will be doing the initial engine swap for me, I don't have the space or facilities to do that myself but I'd like to do as much work myself as I can hence wanting a basic job done at first so I can run it around a bit and basically get it home. Then once it's outside my house I can get stuck into it myself but no doubt it'll go back to the restorers for various bits and pieces!
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Re: AAZ to AHU conversion
ZsZ wrote:I m not very familiar with the rover pump, but I think it is bolt on on the AFN, but you have to enlarge the mount hole on a 1Z/AHU. You can change the mount back to a factory one when you go on e-tdi later.
I've just read this again, would an AFN fuel pump mount fit my AHU? Was planning to buy another mount to get drilled out so I could keep mine for when I switch over to the TDI pump, if an AFN will fit and doesn't need drilling that would save a lot of bother.
- lloydy
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Re: AAZ to AHU conversion
AFN and AHU fuel pump are the same externally, internally i think there is very minor changes
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Re: AAZ to AHU conversion
So an AFN mount would fit my AHU but would still need drilling out? A quick eBay search showed no AHU mounts but a couple of AFN oneslloydy wrote:AFN and AHU fuel pump are the same externally, internally i think there is very minor changes
- syncroandy
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Re: AAZ to AHU conversion
The ECU, pump, injectors and VNT turbo are basically what makes an AFN an AFN. The pump has a different camplate to match the .205 nozzles, and is the same fitment as the 90bhp pump. The VNT turbo is quite different to the 90bhp wastegate turbo, and has a different N75 valve.
Last edited by syncroandy on 02 Oct 2015, 06:58, edited 1 time in total.
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252 GC5 EJ25 AAN L90D
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252 GC5 EJ25 AAN L90D
- NickBab
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Re: AAZ to AHU conversion
Les Shoes wrote:So an AFN mount would fit my AHU but would still need drilling out? A quick eBay search showed no AHU mounts but a couple of AFN ones
I'll be able to tell you the answer to this after the weekend. I've already had my AFN mount modified for the Landy Pump and will be taking the mount off an AHU to hopefully keep as a spare for when I go eTDi. I'll check part numbers etc.
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- syncroandy
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Re: AAZ to AHU conversion
If you're referring to the fuel pump bracket its the same part on 1Z,AHU,AFN & AVG regardless off whether engine fitment was transverse or longitudinal.
Syncrosport (taking a break as of summer 2024)
Volkswagen Transporter, reloaded.
252 GC5 EJ25 AAN L90D
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Re: AAZ to AHU conversion
NickBab wrote:Les Shoes wrote:So an AFN mount would fit my AHU but would still need drilling out? A quick eBay search showed no AHU mounts but a couple of AFN ones
I'll be able to tell you the answer to this after the weekend. I've already had my AFN mount modified for the Landy Pump and will be taking the mount off an AHU to hopefully keep as a spare for when I go eTDi. I'll check part numbers etc.
Thanks but it looks like Syncroandy has saved you the bother!

Exactly the answer I was looking forsyncroandy wrote:If you're referring to the fuel pump bracket its the same part on 1Z,AHU,AFN & AVG regardless off whether engine fitment was transverse or longitudinal.
