So, my interest has been piqued in the T5 5speed into a 200 series. I'm sure there are loads of articles out there and TB has a few, but I am more interested in the Australian perspective of doing such a conversion. @Nicko you touched on this the other day, but I am keen to flesh out the idea and put some meat on the bones of a pathway that appeals.
Some of the 'blurb' from Wonkipedia and the appeal:
A five-cylinder engine gets a power stroke every 144 degrees (720° ÷ 5 = 144°). Since each power stroke lasts 180 degrees, this means that a power stroke is always in effect. Because of uneven levels of torque during the expansion strokes divided among the five cylinders, there are increased secondary-order vibrations. At higher engine speeds, there is an uneven third-order vibration from the crankshaft which occurs every 144 degrees. Because the power strokes have some overlap, a five-cylinder engine may run more smoothly than a non-overlapping four-cylinder engine, but only at limited mid-range speeds where second and third-order vibrations are lower.
In 1995, a high performance model, developed in part with Porsche, was released and designated the T-5R. The vehicle was based on the 850 Turbo, utilizing the B5234T3 engine with a special ECU (Bosch #628) that added an additional 2 psi (0.1 bar) of turbocharger boost pressure, giving the engine an extra 18 hp (13 kW; 18 PS) for a total of 243 hp (181 kW) and 221 lb·ft (300 N·m) of torque. The engine was mated to a 4-speed automatic transmission. The T-5R was renowned as a sleeper car; despite its boxy, understated appearance, it boasted a drag coefficient of 0.29 and was capable of accelerating from 0 to 60 mph (97 km/h) in 5.8 - 6.0 seconds (depending on transmission and body type). The top speed was electronically limited to 155 mph (249 km/h). The vehicle came standard with Pirelli P-Zero tires, providing lateral grip of 0.88 g. The engine tuning was co-developed with Porsche, as was the transmission and other powertrain components.
But which one to choose:
- B5234T3 T3 with different EMS
- B5234T4 T4 Motronic
- B5234T5 T4 15g Motronic
Every cylinder added beyond five increases the overlap of firing strokes and makes for less primary order vibration. An inline-six gets a power stroke every 120 degrees. So there is more overlap (180° - 120° = 60°) than in a five-cylinder engine (180° - 144° = 36°). However, this increase in smoothness of a six-cylinder engine over a five-cylinder engine is not as pronounced as that of a five-cylinder engine over a four-cylinder engine. The inline-five loses less power to friction as compared to an inline-six. It also uses fewer parts, and it is physically shorter, so it requires less room in the engine bay, allowing for transverse mounting.
A five-cylinder engine is longer and more expensive to manufacture than a comparable four-cylinder engine, but some manufacturers feel these costs are outweighed by its greater capacity in a smaller space than a six-cylinder.
From the standpoint of driving experience, five-cylinder engines are noted for combining the best aspects of four- and six-cylinder engines. They generate more power and torque than four-cylinder engines, while maintaining better fuel economy and "pep" than six-cylinder engines. Five-cylinder turbos have been used on more than one occasion in sport and racing applications for their balance of performance qualities. The Volvo S60 R has a 2.5 litre turbocharged inline five-cylinder engine which is capable of generating 300 brake horsepower (224 kW) and 295 lbf·ft (400 N·m) of torque across a large amount of its rpm ranges. The new Ford Focus RS performance car uses the same Volvo 5-cylinder engine, developed (by Ford) to very similar power levels, and is one of the most powerful FWD production cars ever created. Another example of a high power 5 cylinder car is the Audi RS2, with its 2.2 turbocharged engine making 311 hp.
and then why not consider:
- B6294T but other than being a six like this baby...
Mental, yes, and I wonder what your thoughts are?