Walker’s World June 04

We’ve had a few “emergency” jobs this month. Kate with her Pug 205 was the first. Kate had installed an MI16 engine into her 205 and was looking to install some second hand Puma throttle bodies and an old Emerald ECU. I explained that we don’t get involved in fitting components; we only set up to map the system once it is installed. She said she could fit the bodies herself but the wiring was her main concern. Kate turned out to be a very persuasive young lady and we found ourselves agreeing to wire up the Emerald unit for her. The car arrived on a transporter, which cleared off as soon as the 205 was unloaded. Kate was so confident in our ability to get the car sorted in one day that she planned to simply drive it home. The bodies were all bolted in place but the throttle linkage was a bit suspect. The second hand wiring loom looked not unlike a plate of Spaghetti Bolognese.

Next problem concerned the second-hand ECU. This was a real old unit, almost a collector’s item and it wasn’t set up to run with a trigger wheel and a distributor. Rather than try to convert the old system we cobbled up a later 32 bit ECU which had been used for development and Karl then made up a new wiring loom to suit. (no we don’t have any more to sell cheap!) I started looking at the throttle linkage. This was a bit of a dog’s dinner in that the link arm had been extended to slow down the opening rate. Everyone thinks that a throttle linkage is a simple affair – but it’s a lot more complicated than you might think. We returned the linkage to the original design but were stuck for a suitable cable nipple. I found a Jenvey Dynamics one in my tool box but it was too small a diameter. I managed to turn up a little sleeve to adapt it to the Puma linkage and then we had to modify the pedal to stop at full throttle.

To my mind the throttle action was far too sharp with very little travel between closed and full open – but it was getting late so what can you do? The plumbing needed some sorting out too. I turned up a step-down adapter and supplied some new high-pressure hose and clips. Kate made up a bracket to hold the adjustable pressure regulator and after checking for leaks we were pretty much in business. After the final mapping session the engine made 170bhp and we finished before midnight which was a result for us and for Kate who then had a long drive home.

M5

Had a call from a good friend who apologised for only phoning when he was in the shit – but what are friends for? He was involved with rebuilding a crashed BMW M5 into an endurance racer. The car was due to race in France that week-end and the engine had only just fired up – but wouldn’t’ idle properly or rev past 1200rpm. He had rebuilt the engine with a new crankshaft and brand new cams. Nobody seemed sure if it was a mechanical or an electrical problem. It wasn’t our ECU but we agreed to have a look at it. As described the engine did start but misfired and wouldn’t run past 1200rpm. A new crank sensor had already been fitted but to no avail.

We quickly wired up our ECU to just three coils (jury rigged wiring) and the engine revved up on three cylinders so that eliminated the mechanical build aspect. Karl then set about modifying an ECU to fire the six direct-fire ignition coils fitted to the M5 engine. In the mean time we weighed the car on the corner weight scales. The inlet plenum was taken off with a view to checking the throttle balance once the engine was running on six cylinders. We spotted that the plenum had rubber intake trumpets poked inside it. We fished these out and fitted them to the original throttle body. A set of filter socks over these gave us a full race inductions system and saved no less than 8 kilos into the bargain!

With the replacement ECU installed we set about mapping the engine. What a gem this motor is. The engine produces a really lazy 300bhp and feels like it can do that all day long. Just as well because in France it was going to have to run non-stop for four hours. A week later we got the race report: four hours without missing a beat, first in class and ahead of a lot of quicker cars which needed more fuel stops or had mechanical problems. I’m tempted to quote the hare and the tortoise but I’ve never met a tortoise with 300bhp!

Mk 1 1.8T

We do see a lot of Golfs with the 1.8 Turbo engine fitted. These engines are so available second-hand; now that they are installed as original equipment in Golf GTi’s, Seats, Audis and the like. This one was an immaculate Mk 1 which gets regular road use, even though it did look like a show car.

The engine had been bought without injectors and a second hand set had been put in. Trouble was, the engine was capable of 250 bhp at 1.5 bar boost while the injectors were the small ones from the 150 bhp Golf GTi. These engines normally make 200bhp maximum at 1.5 bar boost so they don’t need the larger Audi TT injectors.

All we could do was map it up to a point and then call it a day. Check out the feature elsewhere on this site for advice on injector selection, a flow test isn’t expensive and it could save you time and money in the long run.

Horizontal Radiator

Had a very neat Westfield in for mapping with much better than average cooling. The radiator was nothing special but the installation was. The rad had been fitted horizontally with ducting taking the air in at the front and out through the top of the nose cone. A neat job and very effective.