How to swap 1.6 petrol to GTi 8v

[bigasdrake]

hello, I am pretty new to owning a Bx, but have been interested in them for a good while. I heard from a friend that it's pretty easy to swap any BX engine into any BX engine bay. That doesn't sound too unbelievable, but I just wanted to check with the people who know more about the car than myself. I thought about getting a GTi 8v (or 16v if the opportunity comes) and putting it instead of the 1.6 petrol I have. How easy would that be? What would I need to change on the car/engine? Thanks in advance for the help!

[tom]

Dependent upon your level of expertise, it could be easy or a nightmare. Swapping the basic lump is easy enough but things like instruments will probably need to be changed to fit a temperature gauge and rev counter. The electronics will need attention for an ECU and the exhaust will need changing. If you have a BE3 gearbox, the 16V 5th gear cog set is a very good mod for motorway driving. Plenty about - The valver guys use the TD ones in theirs. The GTI uses a slightly thicker front anti roll bar and a significantly thicker rear one.

[bigasdrake]

Mine has GTi instruments, and a bunch of other options, which surprised me. I guess the instruments would be an easier adventure. I have a friend who does exhausts, I'm guessing he would know someone for the ECU. Not sure about the anti roll bars. I don't have much experience with working on cars, it's something I've recently gotten into. I was told it's a 1/1 swap, all same on both engines (as long as they use the same fuel, of course), so I thought it wouldn't be much of a hassle.

[David]

As Tom has said: it simply boils down to how mechanically minded you are.

I’ve been informed that it would be harder to put a 16V engine in as all the wires are interconnected & travel through the car, but it’s not impossible. It’s easier if you have more parts available.

The GTI 8 valve engine should be easy to fit, as I dropped one in a TXD car just to see if I could. The biggest problem you would have is getting the necessary wiring harness & ecu with the engine. If you got everything that you needed, then it should essentially just bolt & plug together. I think the hydraulic parts & alternator are identical on the 1.6 & GTi.

Most BX engines will physically bolt straight into any BX, with the exception of the 1.4 petrol, which I’ve heard has a different subframe mount.

As mentioned above, then the question of the gearbox comes in, so you’d have to decide what ratios that you wanted, again if you’re more mechanically minded, then you could make your own gearbox. With the exception of the ‘suitcase engine’, I believe that most of the BX gearboxes will physically bolt to any engine. The only differences are the TD & 16V boxes have a different clutch mechanism. The earlier ones have a different shift pattern too, but I’m unsure if there’s any physical difference on the outside of the gearbox.

You would have to change the down pipe of the exhaust at the very least, but possibly all of it. There are 2 types of basic exhaust, one that slots together, with one part going inside the other, & the other type fits up to each part & is held together with the clamps. All the down pipes are different for each engine.

The flywheel has a bigger clutch on the GTi (I think the 8v & 16v use the same clutch). It’s the same size as the TD too. Most of the other cars use the smaller clutch, including the 1.6 & the na diesels.

As far as I’m aware, it’s only the 16V that has thicker anti roll bars, but don’t quote me on that. I know that my BX diesel bars were the same as a GTi. Either way, the engine would fit without messing with those. From the factory, the spheres were different too, but again you wouldn’t need to touch these to make it work.

Let us know if you decide to go ahead with it!

Hope that helps.

[Jugostran]

As was previously stated by David, the biggest issue in going from a carburetted 1.6 to an injection 1.9 (like the GTI 8v engine) is all the injection-specific stuff (eg. wiring). Otherwise the engine mounts may be different, though I'm unsure - it should just slot in.

[bigasdrake]

I will be at the very least try, and will look for mechanics that deal with primarily older/rarer citroens, there should be one close to where I live, so I can get the engine and probably help (or outright pay him to do it all if I don't manage to do it). This is all very helpful, thank you all!

[tom]

Your best bet is to buy a whole car abroad and strip it for parts. BXs are very modular and once the interior and dashboard are out, changing the wiring loom over is easy enough. You know that you have all the right bits and lots of useful spares which you are going to need someday.

[bigasdrake]

I have one for basic parts, since it's a diesel and my daily is a petrol. Parts that I can't get from the diesel are easily found elsewhere, but I was thinking about stripping the diesel and getting another petrol for more parts. I haven't decided yet as I have yet to start work on the daily.