Xud/hdi swap?

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Bsim9751
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Xud/hdi swap?

Post by Bsim9751 »

Hi all. I’ve asked a couple of questions in this area before but couldn’t find much relevant info. I’m thinking I’d like to swap my old xud turbo diesel for a 2.0 hdi. Anyone know what problems I’d come up against?

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GiveMeABreak
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Re: Xud/hdi swap?

Post by GiveMeABreak »

Plenty.

Too many to list, apart from the electronic architecture, air and fuelling systems, engine management systems being completely different, I suspect that the transmission, drive train systems will be entirely different too. Either replace the same engine or change the vehicle for something later - it's not really realistic IMO.

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Paul-R
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Re: Xud/hdi swap?

Post by Paul-R »

Could be an interesting project but would take quite a while and you'd need the donor car there to make sure you're not missing anything. The later the HDi the more difficult it would become.

Just off the top of my head (assuming an early non intercooler 2.0HDi turbo) you'd need to use a Lexia to turn off a bunch of things in the BSI such as ABS, all the air conditioning stuff, wiper controls, indicator and other light controls. radio, etc, etc. You'd need all the correct fuel pipework (flow and return) and possibly a fuel pump.

I once considered putting a 90bhp engine out of our old Xsara into an MGB but we sold the Xsara so the idea went away. Back in the day someone fitted a Renault diesel engine into an MGB but that was an old mechanical pump type.

Bsim9751
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Re: Xud/hdi swap?

Post by Bsim9751 »

Hmmm ok. Exhaust, drivetrain, gearbox, air and fuel don’t scare me. It’s for my Citroen c15 van which I’ve already converted to a turbo diesel so I’ve already tackled those kinds of problems. Electrics are a different matter. What is Lexia? Some sort of software? I’m just after a slightly more refined and tuneable engine for my little project van.

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white exec
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Re: Xud/hdi swap?

Post by white exec »

How about the XUD 1.9 TD, which is all-mechanical (and a good engine), or is that what you have already?

crapday69
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Re: Xud/hdi swap?

Post by crapday69 »

white exec wrote:
14 Apr 2019, 16:00
How about the XUD 1.9 TD, which is all-mechanical (and a good engine), or is that what you have already?


and you could use your old chip fat/oil to run it.

moizeau
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Re: Xud/hdi swap?

Post by moizeau »

crapday69 wrote:
15 Apr 2019, 13:25


and you could use your old chip fat/oil to run it.

If it's a bosch, not a Lucas CAV

Bsim9751
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Re: Xud/hdi swap?

Post by Bsim9751 »

Yeah I’ve already put an xud td in it and it is a good engine. I was just after something a little less lumpy/tractory. Any suggestions?

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white exec
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Re: Xud/hdi swap?

Post by white exec »

A couple of cheap and easy tweaks, if not already done:
- have the injectors serviced/recalibrated by a Bosch service centre
- avoid supermarket fuel, and use 1:1000 of either Wynn's Diesel Fuel Treatment, or Miller's Diesel Power Plus; both of these produce a quieter and more torquey engine. Our 19RD responded really well to both.

The XUD should not be lumpy!

lorddevereux
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Re: Xud/hdi swap?

Post by lorddevereux »

I've seen a few people do this especially to 205s - the early 2.0 HDi 90 and 110 is quite (everything is relative, lol!) easy because the ECU can be quite standalone. In the early uses of the HDi it ran on CAN to talk to the BSI (central car computer) whilst the rest of the car ran on a separate VAN architecture. It will need some sort of remapping (to remove the immobiliser mainly) but there are few places now that can do this sort of thing with HDi's. The hardest bit will be wiring the dashboard/temp sensors etc although not impossible to integrate.

crapday69
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Re: Xud/hdi swap?

Post by crapday69 »

I always think its easier to change the engines in rear wheel drive cars as you have a little more room with the gearbox heading under the car.

wheeler
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Re: Xud/hdi swap?

Post by wheeler »

Xantia & early Mk 1 Xsara HDis were never multiplexed so no VAN or CAN to worry about. The Xantia & early Xsaras had a CPH unit which is a very primitive form of a BSI, the only real connection with the engine to CPH is the immobiliser function which as you say there are plenty of people that can map the immobiliser out.
If you were up for a challenge your best bet would likely be an early non multiplexed xsara or 306 90bhp model and as said earlier you would likely need the complete donor car. You would need to be able to fit a low pressure fuel pump too.

kenbw2
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Re: Xud/hdi swap?

Post by kenbw2 »

Not sure how much it helps, but this guy did HDi -> XUD9 swap in a Synergie: