Hypothetically speaking, what would be the next step in engine modification after installing the parts i mentioned in my earlier post? (Weber 32/36, schrick 304 cam, headers, free flow exhaust and MXD ignition)
I like CR's advice on the S14!! Short of that however, you may want to think about some high-compression pistons and a little head work to get it to flow better. I have 9.5:1 pistons, some mild head work, a 292 cam, Weber 32/36, Stahl header, ANSA exhaust and an electronic ignition so it sounds pretty close to what you've got. It's not terribly radical but it's strong, smooth and reliable (I like that combination!). Dan
Stock S14, depending on whether or not it was an EVO S14, EVO II or EVO III ... put out anywhere between 195 hp (stock US trim) to 238 hp (EVO III motor, Europe only). Other mods could push that number higher though. Even the M10 engine is capable of some fairly respectable numbers. The 2.0L block was putting out around 120-130 hp in naturally aspirated tii form, and around 170-180 hp in turbocharged form in the 2002 turbo. If it were my choice, I'd choose the M10 any day. The S14 is incredibly expensive to rebuild, while the M10 parts are literally all over the place CHEAP. If you mix and match carefully, you can get some very usable power out of the M10 without having to take out a second mortgage (as you would servicing the S14). That and the S14 is a pretty high-strung engine, basically a detuned racing engine. The S14 is essentially a BMW M10 engine block with a M88/S38 DOHC cylinder head (minus two cylinders). The M10, while not as powerful as the S14, has a more usable powerband, is nearly indestructible (limit revs to 6250 if using the standard steel valve retainers, although titanium retainers can extend the rev limit to 6500 to 8000 rpm). The M10 can handle mild to moderate turbocharging using the stock pistons (use the turbo 2002 pistons to allow for more boost). Keep the boost at no more than 10 pounds if using the stock pistons (you can cheat a little by going to a thicker headgasket, which has the effect of lowering your compression ratio). For mild to moderate power, an optimized, naturally-aspirated M10 should do nicely. If you want to run a higher level of horsepower, it's recommended to either go S14, or have a purpose-built M10 turbo engine built from scratch. http://www.usautoparts.net/bmw/engines/s14.htm
The M10 can handle a lot more boost than that as well as put out a little more power. This is an M10 block: These are a couple of the cars it was used in: It was the last stock block engine to win an F1 championship. The Brabham BT52 used 'seasoned' M10 blocks - mostly 1.6 liters with 50-60,000 miles on them - sleeved down to the 1.4 liter specification for F1 at that time. They produced over 1200 hp (maybe closer to 1500, but the dynos weren't calibrated that high when they were testing). So at least you now have a goal ...
Thank you CR KRieger I stand corrected! Even more so, I stand by my preference for the M10 over the S14 in terms of parts availability, ease of service, and cost effective power.