MK1 16V Conversion

the mk1

For those of you out there who own a Mk1 golf and want a bit more power then this could well be the ticket, converting a Mk1 to a 1.8 16v is the cheapest and most reliable way of increasing horsepower by at lest 30bhp. In my own personal case things were a bit different and the power jump was more in the region of 50bhp. Why? Well I converted a 1.6 crab mk1.

Converting a carburetted mk1 presents some very unique issues and if you are converting a standard Mk1 Gti you will have less work for yourself.

Ok so whats on the shoping list then… well this again depends on what you are coming from Gti or carb but the list below should clear that up:

Mk1 Carb

Mk1 Gti fule tank + all pipes
Mk1 Fule pump and accumulator
Mk1 Gti loomb
A 16v engine of your choosing
ECU (and wires)
Heavy-duty rear engine mount off a MK1 diesel
16v break servo + 22mm master cylinder
VWII front callipers (found on most 84 – 91 VWs with vented disks)
4 branch Manifold and exhaust system

Mk1 Gti

A 16v engine of your choosing
ECU (and wires)
Heavy-duty rear engine mount off a MK1 diesel  
16v break servo + 22mm master cylinder
4 branch Manifold and exhaust system

One good tip is to acquire a complete mk2 16v or find someone who is getting rid of there mk1 16v engine to make way for something even more silly (as we did)

Now you should have more or less what you need. But before you take your pride and joy of the road make sure that the newly acquired engine is in the state that you want. If the engine is unknown mechanically then now is the time to rebuild it, other wise you could be doing this operation twice! Fast road cams are also a good idea, 16v engines respond well to a couple of new pipers. We were fortunate enough to have acquired an engine already blessed with new cams, resulting in154bhp.

If your happy that the engine and components are ready then go to work on taking the old engine out. The best way to remove the old engine is, funnily, also the best way of putting the new engine in.There are only two prerequisites, nerves of steal! And a jack you trust with your life!

Ditch that 8v

Mk1 up in the air with the engine out

Firstly loose the water out of the old engine by releasing the pipe at the lowest point of the engine by the water pump, needless to say have a bucket ready. Now unclip the radiator and lift it out there will still be some water in there so pull it out in a fashion that is least likely to soak your nice new overalls. Now set about removing all wires and ancileries. It’s a really good idea to label up all wires and pipes as you go and as you un bolt things put the bolts back in the holes, it is amazing how they go missing if you dont.
After your done all you should be left with a very sorry looking engine and all the break components over the gear box. And theres the problem the mk1 break servo gets right in the way of any attempt to pull the engine out of the engine bay.
Although at first this may seem the most obvious way of engine removal there are many flaws in doing it this way the first is you will need to remove the bonnet then store it somewhere avoiding scratching it.  In may own personal case this was simply out of the question as earlier in the year the cars owner (my girl friend) had forked out almost £1000 to have the cars exterior fully restored. My life flashed before my eyes at the prospect of damaging the paint so the bonet stayed on. This left me with only one option and I must say (in retrospect) it wasn’t as bad is I thought.
The only way is down, using a crane or engine support hold the engine while you unbolt and remove all mounting bolts, starting with the rear mount. It should be possible to remove the gearbox mount completely leaving only the drivers side (UK) engine mount and front bush. I call the front mount a bush as it does not realy support but stabilise removal is easy no pressure should be exerted on this mount when the car is not moving. The mount closesed to the belt is always the most troublesome you may find that the engine gets stuck here if it does try to leaver it out, or use a troly jack to jack up the engine (that may pop it out). Now the engine is free lower it to the ground (can you see where I’m going with this) you may want to get a bit of wood drill a hole in it and put a rope through the hole. place the wood directly under the engine before lowering it. Once the engine is resting on the wood and is free from the car you will need to jack the car up so that you can pull the engine (on the wood with rope) clear of the car. This is no mean feet I very quickly found that you would need a very good jack to do this. My jack came from Halfords, I was in trouble. To the rescue came a large plank of wood (like the stuff builders use on scaffold) slip this toward the front of the car then place the jack in the middle of the car, and jack. The plank spreads out the lifting force of the jack and if positioned correctly will lift the car in a uniform manner (very important). Keep going until there is enough room to pull the engine clear.
At this point it is useful to bair in mind that the 16v is taller than the engine you just removed so you will need to go several inches/centimetres higher when your ready to put the beast in.


the empty eingine bay

Its not all horsepower and shiny inlet manifolds you know, where would you be with out brakes, well in the hedge at the bottom of the road I guess. It is essential to up rate the braking system before the new engine goes in trying to stop a stock 8v Gti is scary but a 16v well that’s suicide. Plus you will find it very hard to fit the 16v with that massive master cylinder. Now is the time to ditch the lot servo and master cylinder should be changed for the 16v ones if your standard callipers do not have VWII on them then find some that do they are almost identical but are slightly wider so to alow a vented disk. If you run 14” wheels you could upgrade to the late 16v Gurling calliper (256mm disks) or if you run 15” wheels you could upgrade to G60 Gurling callipers (280mm disks). The choice is yours.
Before you install the master cylinder it is worth pointing out that you will need to remove the plastic bottle and turn it round this will give the distributor more space.. well space actually.

Wiring loom

The wiring of all mk1s is based on the same fuse box. The 16v or 8v GTi's are similar and need less work. The main addition here is the Idle stabaliser, if you intend to fit it. as we used the 8v setup this wasn't necessary. Therefore the only wiring job was to add the fuel pump loom. This requires crimping of wire with special connectors that go in to the fues box connector blocks. These can be obtained from vehicle wireing products.

The gearbox

In my kneck of the woods there seems to be a running theory that a 16v in a mk1 will eat the original 16v gearbox, and that a 8v Gearbox is a much better proposition. I am not a gearbox person (yet) so I choose to be highly sceptical of this. Especially as after 2monhs of running the 16v in my girl friends mk1 the 8v Gearbox packed up and had to be rebuilt.
Even if this is all rubbish there is a more tagible case for using an 8v gearbox as aposed to a 16v number. Firstly the flanges on a 16v box are bigger and will not mate to your drive shafts. And secondly revs, the 8v box provdes a different set of ratios notably less revy in 5th. Don’t worry this will not impact the performance you will still be able to accelerate from 70 (not that you should, I don’t….aint my car) mph as if you were just leaving a set of traffic lights.


The 16v

the new 16v engine on the floor

If your 16v engine is out of a MK2 golf then all of the engine mounts must go. Unbolting the old mounts should prove no great chore, fitting the new ones is a bit more involved. With the old 8v and the new 16v in close proximity get go about removing each mount in turn. Discard the rear mount, as this is not up to the task of holding the bigger engine. Bring from your pile of shopping the heavy duty Mk1 diesel mount. Now put on the top gearbox mount ensureing that the bolts are the correct way round (head facing the engine). If you need to change the gear box it will become immediately apparent why that is crucial. In the traditional fassion I have saved the best until last, the drivers side or front engine mount (yes I know its on the side really) is by far the most involved one to fit as it is necessary to remove belts and covers and more belts to attach the mount in place (unless yours is different) make sure the holes are clean as they will not have been used for anything in its life in the mk2.
By now it should be very apparent that the 16v engine is nowhere near as easy to move as the old 8v. to move the engine again use a bit of wood and a rope to lug the engine accoros the floor, this method will also reduce damage to the sump (I am of cource assuming that you don’t have a trolley J if you do you can use it!). Attach the 4 branch manifold to the cylinder head before the engine goes in. Always check the union from the manifold to the rest of the system and make sure that they all fit together. In some cases a reducer is needed because both pipes are exactly the same size!
Remove the distributor cap to gain a bit more space wile monuvering the engine in to position. You will need at least one friend to help (probably), and several more to stand around swilling bear and offering the odd word of encouragement and technical advice.
Back to the plot.. If your jack, and your nerves, have recovered from the last time it is again time to raze the car up. With the 16v in front of the car in the correct position have you mate keep an eye on the top of the engine in relation to the bottom of the front panel. When the car is high enough he/she will jubilantly inform you, and breathe a sigh of relief that nothing “expensive” has happened. Now Get that engine in to the centre of the engine bay and gingerly start to lower the car. As the car comes down you may need to re-position it slightly. Once down, strap the engine to a hoist or crane and lift it in to position loosely insert all the bolts before tightening then release the crane. Almost there now.


engine installed in the car