Mini Stock Engine Build - Heart Of The City...Boy

Prior to jumping into that part of the build, our City Boys spent an evening pulling the motor and stripping it down in preparation for a journey south to Lake Worth, Florida, and our good friends at Race Engineering. While owner Bob Koch and his crew stock a complete line of parts for V-8 engines, they are known as four-cylinder specialists, both import and domestic, which in our case is perfect for the Ford 2300 engine that came out of our Fox.

Race Engineering's specially designed products can get an obscene amount of horsepower out of four-cylinders. And while we have a rule book to adhere to, Bob Koch tells us that there is plenty of room to play. But before we can send the motor down south we first have to get it out of the car. Since we weren't using much of the top end and accessories on the motor, we didn't much care about salvaging these items but as you can tell from the pictures, getting the motor out of the car still proved to be a small adventure.

Once the motor was out of the car, we began the disassembly process and found the little 2300 to be in remarkably good condition. While it was completely stock, a brand-new oil pan made us think that someone had already been through it once. We would find more, there was nice cross hatching on the cylinder walls and even the head gaskets were in great shape.

Our block happened to be a small-main E89 block, which would make Bob smile. You can find other blocks in four-cylinder Mustangs with larger mains, but the guys at Race Engineering prefer the E89 because the smaller mains translate into a reduced main bearing speed.

Based on a thorough reading of the rules and a conversation with the track tech, Bob chose specific parts that he wanted to use in this build. The goal is to be as light as possible and to reduce internal friction wherever possible, all staying within the rules of course.

Why do we want light? Light parts reduce internal rotating weight which in turn increases engine acceleration, very helpful coming off the corners. It also helps driving deeper into the turns as it assists in engine braking. Reduced friction also improves acceleration.

We ended up keeping very little of our original E89 block and some of the first things to go were the stock pistons. Since the track has a flat-top piston rule, we will install Race Engineering's ultralight pistons by CP Pistons. This unique design, which is proprietary to Race Engineering, is built on a strutted CP forging which yields a remarkably low weight.

These Race Engineering/CP pistons weigh only 276 grams. We shed even more weight because the wristpin supplied with these pistons weighs in at just 74 grams, while normal aftermarket pins tip the scales at a minimum of 117 grams.

Fortunately for us, the rules don't restrict ring selection, so we used Race Engineering's new Super-Metric ring pack. These rings measure 1.0 (0.039-inch)x1.5x2.0 mm instead of the more common and wider 1/16 (0.062-inch) or 5/64 (0.078-inch) rings. Thinner rings increase seal thanks to their improved ability to conform to the cylinders. Believe it or not, thinner oil rings generally have better oil control as well. Thin rings induce less drag and reduce flutter at TDC and BDC, especially at higher rpm, another bonus.

In the course of our rod discussion, Bob mentioned that he even offers a 5.930-inch rod that he likes to run on 4/10 and longer tracks, but since we're not running Bristol Motor Speedway with this car (yet) we stuck with the 5.840.

Race Engineering's H-beam rod weighs less than 500 grams. For comparison, stock 5.2-inch rods weigh around 630 grams.

Unfortunately, the rules don't permit any lightening of the crankshaft, so Bob and company left the counterweights and stroke alone. They did however prep and balance the crank, and as we mentioned earlier, we do have an advantage with this smaller main E89 motor. Those smaller mains mean decreased bearing speed for reduced friction. In addition, Bob turned the rod journals down to the standard 2-inch Chevy journal size which not only reduces friction, but also adds strength by allowing increased fillet sizes.

The mains are then align honed to ensure proper main bearing clearances. Bob says he typically shoots for 0.0027-inch on average, however, he can go a little tighter with no problems as all bearing clearances are measured with a dial bore gauge during assembly. Unlike some shops, Race Engineering never uses plastigauge. This is critical as many engine failures can be traced to improper bearing clearance.

Finally, the block is machined for a mechanical fuel pump. Our motor was originally fuel injected as most small-main blocks generally are, however, they still have a mounting flange for a mechanical pump. So all you need to do for the conversion is to machine the opening.

Step number three is to turn the rod journals to 2.000-inch Chevy small journal, which also generates larger fillets for added strength. However, care must be taken during assembly as V-8 bearings aren't chamfered on both edges and narrowed bearings only clear one side. So, V8 bearings must be checked and modified. Race Engineering stocks and installs bearings that have both edges chamfered. This whole process results in reduced bearing speed, proper clearance (vertical and horizontal), and a stronger part. Finally, the crankshaft is carefully balanced.

What's Next?
In the next installment we'll follow along as the guys at Race Engineering begin putting the internals of the engine together. What we'll have when we're finished is a race-prepped short-block assembly that's ready for final assembly and a session on the dyno. Stay tuned!