250 is doable, yes. But you can make 250 hp, at the wheels, with a bone stock 1.8, reliably for tens of thousands of miles. I know, I've done it. No need to build anything. And this isn't even getting into area under the curve. The 1.8 will make much, much more torque, everywhere. A built 1.8 will get you to 350-400 without breaking a sweat.
In a naturally-aspirated state (without a turbocharger) the Miata’s inline-four runs optimally with a 2.25” diameter exhaust installed. A larger diameter exhaust won’t necessarily hurt performance (unless you go for 2.5″ or more in diameter), but you won’t see a boost in horsepower or torque with anything larger. 10/4/10 5:34 p.m. I'd love to see some Miata 16V head porting, I currently do bowl work, and porting on 4AG heads. Here are a couple of my photos. Intake ports before and after note nothing done to the horizontal part of the port, the bowls were blended, and the guide bosses minimized. Exhaust port in mid work, left side shows all the major
Avg. Gallon of Gas : $1.12. Total Car Production : 9,782,997. 1990 Mazda Miata FAQs (show) Article Image gallery Specifications Profiles Recalls Production figures. 1990 Mazda Miata technical specifications and data. Engine, horsepower, torque, dimensions and mechanical details for the 1990 Mazda Miata.
To your kit..I think a small turbo is going to do more with a 1.6 than a supercharger. I had a small garrett on mine and it had full boost by 2800 - 3000 rpm. Lag was just about non-existent. 200 hp estimated power. I never dynoed it but the 0-60 times calculated against weight were close to that number.
The short-block as built here could handle significantly more if needed (proper ring gap aside), and 600 hp would certainly be a safe number for this short-block. We found a 5.9L Magnum from a
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how much hp can a 1.6 miata handle