Luck of the devil

My whole intention with building this car may seem a bit sacrilegious to some, but the one thing that Volkswagens have always been lacking in is power. It is for this reason that I intend to build one of, if not the fastest T34's around, (I'm not really a boy racer, I've just decided to take my mid life crisis a bit early). Most of what my plans include will not permanently change the structure of the car, and so if I decide, it could easily be changed back to original.

The only major structural change I will make is to change the roof for one with a sunroof in, but then again I'm sure that most people wouldn't object to that (except the true purists). I had a bit of a lucky chance meeting with one Clive Richardson, now the Type 34 secretary (I think) of the Karmann Ghia Owners Club, who owns a very tidy RHD sunroof model. It was at one of the infamous Karmann Connection swap meets, I spotted his car and decided to go and have a chat with him. It was whilst in conversation with him I mentioned; "wouldn't it be great if you could get a complete roof..........", well the gods must have been smiling at me that day, as Clive then told me how he had bought a complete roof from someone in Germany, so as he could get the electric motor to replace the faulty unit in his car, what was more was that he was prepared to sell it. We struck a deal and Clive even delivered it to me.

The real heart of the project is the motor, a 2.3 Litre Type 4 unit, with a Ray Jay 0.8 AR turbo, and a 50 HP Nitrous kit. I've done lots of research on All aspects of turbo charging, and nitrous injection, and feel confident that I could get a very fast reliable motor together. (I met a guy from Sweden who ran a road legal home grown bug, which he used for strip racing, he ran well into the nines using a 2.3 Fuel injected turbo'd Type 4 motor, with a hybrid Garret T3 exhaust/T4 compressor turbo,).

The key to any turbo charged engine is to have a good fuel delivery system, and where most designs reach a limitation is their use of carburetors. It was once said that it was impossible to run a blow through system on anything over 5psi, although this 5psi rule has been proved wrong (Lotus Esprit Turbo's used just this method successfully running boost pressures of 12psi), both methods of carbureted turbo induction have their drawbacks. The biggest problems are fuel enrichment under boost conditions, and fuel separation within the inlet manifold. Carbs don't really have a good proportional control band, and tend to provide a very unreliable response when used in this application. (Remember a turbo engine running too lean on boost will burn out valves in an instant. Also as any air-cooled owner will vouch, when it gets cold carbs begin to ice up, can you imagine how quick this would happen in a suck through system, where rather than having an induction pressure of say 1-2psi you are running at 16.

The best way to deal with this problem is to use fuel injection, some units also benefit from a host of other features, such as extra injector control for boost enrichment, water injection or nitrous applications, soft rev limits, shift lights, boost control, switch-able program settings that can be changed `on the fly`, nearly all systems use a wasted spark type ignition system, this coupled with the crank triggers that these systems use means that you can chuck your inefficient distributors away. It is a well proven fact that bottom end power gains are over 25% better than using carburetors, how do you think that they can get a 1.25 Litre fiesta to go so fast? (sic).

One of the best systems that I've seen is the Haltec E6 unit, although I don't think that they have any distributors in this country, (I think it's an Australian company). I did at one time think of making my own system using an early Ford Sierra Cosworth brain, (the brain only controls the fuel injection, and not things like ABS, traction control etc. as most other OEM brains do). However although software is available to program the chips for these units, its much easier to get an after-market unit where you just plug your laptop into the brain, download a preset set of injector timing parameters, and tune them up as you drive around, (not all of us have a rolling road in their garage).

Nitrous sounds like a scary thing to have on a turbo motor, but truth be told its not used the same way as with a normally aspirated engine, the nitrous is only active up until a certain boost pressure, (full boost or just below) this in effect gets the engine up to boost quicker and eliminates any turbo lag, it is possible to keep the nitrous switched in when full boost is achieved, which is fine if you complete professionally and tear your engine down after every pass, however I don't think that it is a viable proposition to use it this way in a street motor. (engine life expectancy-One day if you're lucky). One great advantage that nitrous provides for turbo engines is that it considerably lowers the charge temperature, practically super cooling the air entering the engine, which is great news as turbo charged engines run phenomenally hotter than normally aspirated engines. Because of the way that the nitrous is used it also lasts considerably longer than in other applications.

The particular turbo that I am using is a bit oversized for a 2.3 Litre engine,(0.8 AR), whilst this gives very good high end power, it does also create a lot of turbo lag, which is where the nitrous helps out, eliminating the lag so that it spins up quicker. The higher RPM gains with a larger turbo mean that whilst most smaller Turbo's compromise their high end operating range to eliminate lag the larger unit will provide more power further up the rev range.

One modification that I intend to do but have not been able to find out too much about, is to fit a Porsche 5 speed, there's no way that I'm paying the extortionate prices that they want for a Berg 5 speed,( after all its still a VW box, and they're not that strong). Volksworld did an article once, but it wasn't really that informative, they told you how to reposition the gearbox mounts so that the gearbox would mount into the frame-horns of a swing-axle Beetle, but no mention was made of what drive shafts you should use, or how they needed to be modified, I can only assume that you had to cut and shut a Porsche inner with a VW outer to get the splines correct to match up to the hub. Although this sounds extreme I did have some drive shafts converted like this before, and they ran fine. If anyone has any info, then please let me know.

There is one cat that I am definitely not going to let out of the bag, that is my plans for the front suspension, think steering box, think not. All I will say is full height and camber adjustment, rose-jointed.......................

Well, I'm all excited now, I think I'll go and take the angle grinder to the roof.