There are many ways we as enthusiasts can measure a builds potential or worthiness, but the way I've always looked at this is simple. Power-to-weight ratio minus the likelihood of failure factor. Lets say this factor is a scale from .010-.050, .010 being an oem engine while .050 represents a turbo kit thrown on a normally n/a stock engine running a base map.
If I had turbocharged the original 1.5L to 170hp, with the engine's power output being divided by the weight (2368) of the vehicle....we land at .072. I probably would have gotten a tune so lets say the reliability factor is .040. Subtract .040 from .072 and that leaves us at .032.
Now with the 2zr Im at 139hp with only a header, so the power to weight ratio on a full interior car is .058. and lets say the reliability factor is .015. subtract these 2 and you end up at .043. Risk assessment complete. So, now what can we do to increase our number without sacrificing any more reliability, this is a budget build after all...
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