Upgrading An Old, Tired, Single-Port 1600cc Engine

Years ago, we decided to have some fun upgrading an old, tired single-port 1600cc. The idea behind it was to use only bolt-on parts, and not get into pulling the heads, splitting the case, or that sort of thing. We figured this would be a good example of what an average VW enthusiast might be able to do himself in his garage without going too deep. We wanted to learn exactly what kind of improvements we could get, doing just that.

So we schlepped this old engine off to Chico Performance Racing and put it on their dyno, as we didn't own one at the time. Initially, as it was, it made a whopping 33 horsepower!

Figuring that was a bit on the low side, we took it back to the shop and gave it a quick tune-up, valve adjustment, and oil change. Then we took it back to Chico's place for another spin. After the tune-up it did much better, now peaking at 39hp, which we figured was probably a realistic number for what an old, stock engine would do. This served as our baseline for power output.

Next, we pulled a bunch of the old dirty stuff off the engine and cleaned it up a bit. Knowing that a few chrome parts would make it go faster, we added a little of that. We also changed the fan shroud and engine tins to make it at least look a little better.  We added a degree pulley to help set the timing, added a 009 distributor, and pulled off the exhaust. We decided to really up the ante and run a 1-5/8" merged exhaust with a stinger, just for kicks.  Here's a photo of progress:

As I said before, it was a long time ago.  The photos are pretty poor!

You might notice the intake manifolds.  Yes.  We installed a pair of Kadrons on this motor. The carbs were a little souped up, but heck... we were there to learn something. They had 32mm venturis and jetting that we had used in a similar previous build. We knew that car got faster, and we really wanted to know how far we could go, so why not? Oh yeah: We also added velocity stacks!

Once the carbs and exhaust were on, we added 1.4:1 ratio rockers to give it a little more flow potential.  Knowing we had something fun happening, we drove it over to Chico's for a 3rd dyno pull.

We couldn't believe the effect it had. We made an unbelievable 57 horsepower and the power was still rising when we decided to shut it down at 5000 RPM's. We figured a good motor that made 57 horses was better than a broken one that might have made 60 or more.

All in all, we did learn something that day.  We learned that we could make pretty darned good power with measurable results. We made almost 50% more horsepower!!! It's pretty hard to argue with that. It's like adding another two cylinders on to that old, tired engine. We had that engine for awhile ourselves, and eventually passed it on to a customer, who drove it for years.