MK 1 to MK2 1800 conversion

Having a bit of a problem, brought my mk1 a few weeks ago and it had already had the 1800 16v lump dropped in, its running on twin webbers so no ECU. Its not firing on all cylinders and some1 has said i need to change the dizzy and wiring, but to what??? i've heard people have used 205 dizzys… does this work?

Can any one help?

     

"Twin webers so no ECU" - the 16V doesn't have a fuelling ECU anyway, so I don't know why you think that running carbs eliminates an ECU here, it eliminates the mechanical fuel injection, not the ECU.

"Not firing on all cylinders" - how have you diagnosed this? Maybe its something as simple as the ignition leads are on the wrong order. It doesn't mean you need another dizzy. Wiring - which wiring - the ignition leads? Possibly. Low tension wiring - nope - if its firing on SOME cylinders, the LT side must be doing something vaguely right.

205 dizzy - more like, you've heard that the 205 dizzy cap can be used on the 16V dizzy.


What kind of ignition system does the car have at the moment? Its possible to do it a few different ways, the one I'd choose is to use the original 16V dizzy and 16V ignition ECU (even with carbs), and with the 16V servo and master cylinder upgrade, you can still use the original 16V dizzy cap. Alternates are using a dizzy off a small block Mk1 Golf (or equivalent) engine.

If you use the 16V dizzy but without the ECU, you'll obtain no advance on either load or speed. The small block dizzy contains mech and vac advance, the 16V dizzy & ECU does advance by sensing load (via a built in MAP sensor), speed and coolant temp.

1.9 pug dizzy does fit, it has mech advance too and I've been reliably informed it works quite well. 1.0-1.3 dizzy will also fit & work, though obv the ign curve wont be ideal.

as above though I'd stick with the KR ign controller setup, better match.  If you go for the servo upgrade I recommend a MK3 2.0 16v ABF dizzy cap and rotate dizzy 180 degrees, you get much more clearance for brake lines and dont have to fit the reservoir backwards like you do with a KR dizzy cap.  Only issue is you need a longer king lead, I made my own as luckily I had a spare set of leads with removable ends!  An 8v one would also work.