================With even mild peripheral porting and boost, turbo 13Bs in aircraft have no trouble exceeding 200hp at 5500 rpm, and they'll happily turn faster than that and make more power.
True, you can push any Engine to make more hp, but there is a Point in Continuous use for Hours like on a Plane where you can go too far! You can do the Porting, you can use the High Temp O-rings, the Ceramic Apex Seals, and today you do have better Synthetic Oils to use. Just as every Plane has a limit on Prop Size it can use! You can use the Light Weight Housings to Save on Weight. How much Boost is too Much for Aircraft use? Finding a Reliable Reduction Drive was the biggest problem for many Years. For Endurance, a Long Service Life your probably looking at Max 6500rpm! 6500/2750rpm = 2.363 Ratio. As I said, the output of late 13B-T was 185 hp (138 kW) at 6500rpm! To make 200hp and using a lower Max rpm, means more Boost!
4500rpm/2750rpm= 1.636 Ratio!
5000rpm/2750rpm= 1.818 Ratio!
Is there even a Redrive in them (2) Ratio's to meet his Mission?
Wouldn't a 20B 2.0-liters be a better option? The 20B-REW in the Eunos Cosmo is referred to as the production 20B. In this guise, it’s remarkably powerful, putting out 300 horsepower and 403 Nm of torque thanks to the combination of 2.0-litres and sequential turbocharging at just 0.7 bar of boost = 10.15264 psi. I didn't see at what rpm it was rated. It would be better to Detune a 20B to his desired 200hp.
5500rpm/2750rpm= 2.0 Ratio!
6000rpm/2750rpm= 2.181 Ratio!
6500rpm/2750rpm= 2.363 Ratio!