1990 Skoda 136 Rapid - The K-Rapid project!

Ok,

I've had it about a year, it had spent about the last 6 in a council lock up, having blown its head gasket. Set of jump leads on it and to the owners disgust, it fired into life 2nd turn of the key!

I got it for a steal (like under £100) and dragged it home. It turned out that the aluminium engine block had warped (not unknown on these) so I ended up bolting it to a mates dad's miller and skimming it flat.

I had the cam reground to Kent SK3 profile, which is a lumpy 290 duration cam.

The head is from a MPi felicia, and suffers from rubbish beehive conical valve springs which start to float around 5000 rpm, hence the choppy curve.

Induction is a standard tiny 30mm weber replacement, so future is either bike carbs on a manifold (which I have) or maybe a 32/36 weber from a pinto.

Exhaust is a Czech sourced 4 branch system, and makes yer ears bleed....

I chopped the front springs 2.5 coils to level the car, and its running 15" Empi wheels.

Is it Retro enough.....??

Got my spare head sorted (thanks again Andy)





So can now use double valve springs to avoid the MPi conical spring bounce.

Just cleaning the bike carbs (32mm Mikuni's from an FZR600), fit the elec fuel pump and then dyno time again.....

Right, a bit more work done today, finally got the 32mm Mikuni bike carbs on and took it for a blat





1st impressions seem very good. It starts and runs when cold a lot better than it did with the standard replacement weber. Driving around, the carbs are very smoothand do seem to give good performance.

Next step is build up the ported head and through it together properly and see how it runs then.

Filterwise I'm thinking something like a large tupperware box (don't laugh..... ) ducted to a cone type filter underneath the lid vents.

cool rapid! fond memories if my black one, could you not use the standard airbox from the bike engine?

Had a proper blat last night, and it goes really well with bike carbs, a lot better than the standard replacement weber, even the girlfriend can drive it now......

The power delivery is seamless and from even from cold it starts and idles perfectly (non of the juggling with the choke like I had to do with the weber) and no flat spot between 2 and 2.5k revs. It just goes. Brilliant

Spoke to BoggBros and next job is to make up an airbox. They reckon the clamp on filters do nothing for bike carbs, plus they are going to be breathing warm engine bay air, never good.

So plan is to fold up an alloy airbox and duct it with a large cone air filter under the lid vents. Magic!!

very very nice job sir and an uber clean car,you should put a video up of the noise of it with the bike carbs on now

top job,do you get induction roar at high revs(i hope so,sniggers)love the car mate!!.

And it goes like this on my mates private road:

Thats pretty cool, my dad had one of these back in the 90s, cool little cars. Love the fact you're running bike carbs on it.