Mk3 8v Engine into Mk1 Convertible

Hello All.

I'm sure these questions will have been dealt with before but I can't seem to find the relevant info. in the forums, so I apologise if this has been answered Ad infinitum already. Please feel free to direct me to the answers if they already exist.

I own a 1987 Golf Convertible. I live in Australia and, unlike tin-tops, the Convertibles were not available new from VW dealerships. I think mine may have been imported from South Africa or possibly New Zealand. It came with a 1.6 litre engine and Pierburg carb. The Pierburg was no end of trouble and I eventually replaced it with a Weber. Even with the Weber it's no scorcher. I understand that Convertibles weigh some 100kg more than the equivalent saloon. With this in mind I have bought a 1.8 litre engine from a 1995 Mk3 Golf which came from the factory with a single point fuel injection system but has been sold to me without that system or the inlet manifold. The bloke that sold it to me told me said that it would basically be a straight swap. My questions, therefore, are as follows:

1. I can transfer the inlet manifold from the 1.6 motor to the 1.8, but I would need to add an electric fuel pump because the current 1.6 has a mechanical pump. What pump is normally used and where are they normally fitted?

2. The bloke that sold me the 1.8 said that I would need to change the engine mounts somehow, but he didn't really explain how. He has sent the engine mount plates (sorry if that's confusing). How do I do this engine mount changeover?

3. The Mk3 motor has a different alternator (bigger, I think) to the Mk1 motor with a different connector plug. I'm assuming that the easier thing to do is to swap the plugs over rather than the alternators. What's the usual procedure here?

4. Lastly (at least for the moment). I'll be doing this conversion on a shoe-string budget so I don't want to spend money if I don't have to. However, I may as well do everything that makes sense with the engine out. Should I fit a clutch kit while I have the engine out? Is fitting a clutch necessarily an engine-out job? Or is it such a horrible job with the engine in that you'd want to remove the engine from the car and it would therefore make lots of sense to do it during this conversion?

I'd be very grateful for any help with any of these questions, thanks, David Hynd.

I have'nt got an awfull lot of experience with swapping a carb engine for single point injection, however I had my 1.8 carb engine swapped with a modified mk1 1.8 GTI engine with the 2.0l mk3 bottom end, This was then, a very high torque and fairly quick car.
I had to change the fuel lines on mine and new lifter pump and relay. You will need to consider all of this.

As for the clutch it is alot easier with the engine out and if your clutch is worn even slightly it would be easier in the long run to change it now. Changing clutches yourself with the engine in is not impossible, the gearbox needs removing and then the hardest part is getting the input shaft to match up after!

I would suggest that you need to sorce the inlet manifld and injection system to go with your new engine, unless you want to mess around re-jetting your weber to cope with the extra cubic capacity. the exhaust shouldn't be that different tho.

Thanks, Jeevesraf, for the info.

I probably didn't make myself very clear in my original post, but I'm not intending to use the single point injection system on the new engine. The engine actually came with no inlet manifold so I'll have to use the manifold off the 1.6 engine and the Weber carb. I'm currently running the 1.6 with a Weber 32/34 carb that came off a 1.8 litre engined Mk1 Golf Cabriolet, from the U.K. as it happens - thankyou Ebay - and is still jetted for the 1.8 litre. My 1.6 runs with the carb as is, but too rich and doesn't like re-starting once warm but I don't want to waste time re-jetting when I intend to put it on the 1.8 litre anyway.

The advice about doing the clutch while the engine's out sounds like good advice, thanks.

I'll have to source an external electric fuel pump because unlike Mk1 GTIs my vehicle has a different fuel gauge sender which doesn't have an integral pump and is accessed from under the back seat, unlike the GTI which is accessed from in the boot and the sender is mounted with a fuel pump. At least this is what my research has told me. I'm no expert.

The thing that I haven't been able to find any information on is what to do with the engine mounts. I'm a bit surprised that putting a Mk3 Golf engine into a Mk1 isn't a reasonably common swap? And surely it makes no difference what type of carburettor or injection is used, the engine would still mount the same way. Anyway I'll keep searching.

Thanks for taking the time to reply, David Hynd.

Mountings not a problem, mk1 mounts should fit the mk3 engine.

what engine code is the engine before you put any effort into it? some of the mk3 1.8 engines were low compression and not much more powerfull than the 1.6 thats in there now.

also you need to change the dizzy for the old one, the mk3 dizzy is for fully electronic ign and has no advance system.

 fuel pump wise people have used an in-tank pump from a later mk1 cabby/scirocco or mk3 polo, but not sure if any of these models is available where you are. if not, a facet pump and a suitable presure regulator will sort you out. run it from a k-jet mk1/2 fuel pump relay without a rev limiter in, this will be safer than just running it off ign as in a crash it will cut out properly