It ran through the dawn of tuning domestically produced cars and used that as a basis to advance to Porsche. Mr. Mamoru Ogose, led by Group M, has been studying the attractiveness of Porsche ever since. For him, the biggest motivation is "engine construction".
The research on Porsche engines underlies the activities of Mamoru Ogose. I've always been tired of curiosity, thinking about all the specifications, and actually working on them. The group M's business he leads is diverse, but at the core of it is the restoration of classic cars centered around Porsche, and at the core of this is engine overhaul and a tuning approach with a unique mindset.
“In the 1960s and 1970s, when I was devoted to tuning domestic cars, I was fascinated by the driving of the 911, and when I opened the engine for the first time, it was a shock. At that time, we made a needle hole for domestic cars. What I managed to tune in was that Porsche was equipped with it from the beginning. It started with the strength of the material itself, and it was highly accurate and consistent-everything seemed to be a more sophisticated precision machine, and it felt like a distant world. had"
In this way, Mr. Ikoshi has a sudden commitment to Porsche. More than 40 years since then. Even now, he constantly receives requests for overhaul and tuning. Work started on that day with a 2.7-liter engine on the 911 Carrera. It is said that it will be posted in the narrow during full restore introduced in the previous issue. The 2.7-liter engine is faithfully revived as it is genuine, but with a slightly higher compression [high compression] specification. Specifications such as "genuine + α" that make good use of features are Group M's specialty.
Actually, this engine was in a bad condition. Rust in the combustion chamber is likely to erode and decay, and if an unfamiliar person sees it, he or she will give up. However, if we start with the technology we have cultivated over 40 years and have a stock of parts and know-how on how to obtain parts, we can still fully reproduce them. No matter how bad it is, the Okuetsu-ryu is the first step to accurately determine the condition.
"First of all, I have to thoroughly disassemble and clean all the parts. I clean the parts that seem unusable because I can see them. And I check the condition accurately by checking for cracks. It can be a hint to see the condition of the car as a whole, and I think it may be used for another occasion even if it cannot be used this time. "
It is essential to understand the condition of bolts and nuts that fasten parts. A typical example is the 911, which uses stud bolts to connect the crankcase and cylinder. Not only the bolt itself, but the crankcase of the 911 of these days was made of magnesium, and the wear and corrosion of the screw groove can be seen. That is why he always disassembles everything, checks bolts and grooves, and cuts new screw grooves so that the specified torque can be applied.
“We prepare all the parts, such as processing and procuring new ones, and then assemble them at once. We do not assemble them in stages. It is more efficient and less troublesome twice. I want to minimize even the stress at the time. It's a feeling that I reproduced the Porsche assembly factory at the time and assembled it by myself rather than by assembly work. ''
This time the displacement is unchanged because it is based on a 2.7 liter engine, but in some cases it is also a good idea to convert the 2.4 liter engine to 2.7 liter. If the original displacement is 2.2 liters, go to 2.4 liters, if 2.4 liters, go to 2.7 liters. For example, the method of stepping up only the engine displacement to the next generation is often completed only by replacing [processing] the piston cylinder. The stroke is unchanged and the camshaft and fuel pump can be used. By simply resetting the compression ratio and even adjusting the fuel level, it will be easier to ride while satisfying reliability and durability.
Mr. Ikoshi's own 1972 911S [pictured above] and 1988 930 turbo [pictured below] are full of his ideal engine. The front car is a 2.8 liter model that has been designed and processed by itself while combining parts of all ages and has an output performance of nearly 300ps. The rear car is equipped with a large turbine while converting the 3.3 turbo to 3.4 liters, and the maximum output is 600ps. It is the ultimate approach with two axes, NA and turbo.
So where to put the compression ratio? The compression ratio of the air-cooled 911 is set individually for each grade, and the displacement increases with each passing year, but on the contrary, the compression ratio was lowered. It started at 9.0 in the 2.0-liter era, went to 9.8 for S from 1976, and was 8.6 for T. However, in the 2.4-liter era, it was lowered to 7.5-8.5 due to exhaust gas measures, and even after that Carrera RS 2.7 stopped at 8.5. According to Mr. Ikoshie, the approach of high compression using "about 9.8" in S in the 2.2-liter era as a guide is effective, and this individual will also do so.
Be sure to disassemble and clean the engine and check for cracks. Then, the condition is determined. Identify the corroded parts and skillfully recover them by argon welding or cutting.
Once the combustion chamber is decided, consider the mixture to be sent into it. Whether it is the Kugel Fischer [Bosch] fuel injector called Mechapon, the next-generation K JETRO, or the carburetor. You can think of various options. Each has its own charm, so you can choose according to your taste and the stage you are driving. This time, we will overhaul the genuine Mechapon because we will just follow the genuine one.
“We carefully assemble each of the complicated mechanisms that use so many parts by carefully examining their dimensions and weight to minimize the number of intersections, and then assemble them by ourselves. Originally, I like to fix broken things, I enjoy making plastic models as well, so I can't stop building an engine. If I couldn't find it interesting, I'm sure I'll quit my job soon, "says Mr. Ikoshi, looking at the engine, which is placed in a factory where tools and parts are arranged in a logical manner. Even if it looks like rubbish that has decayed for over 40 years, it looks like an irreplaceable treasure to his eyes.