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Old 11-09-2021, 08:29 AM   #23
Irace86.2.0
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Sometimes NA engines do really well with boost. A turbo engine might have lower compression for knock resistance, stronger rods for the extra torque and smaller intakes for faster spool, which all sounds good for boost, but then the manufacturer is also trying to use a small turbo with low end torque. These turbo engines don’t rev out well because they weren’t designed to breathe well, and they still have similar limitations on adding more power; their rods will still buckle when 50-100% more torque is applied. For instance, the 1.5T in the Civic Si is a boosted motor with similar horsepower to the 86, but aftermarket power is typically limited to 300whp, where the 86 is closer to 350whp, so is the FA20D a better boosted motor? Not necessarily. Just saying.

The advantage of our higher compression motor and NA/high revving engine is a JRSC is well realized, where the top end torque delivery would be wasted on a low revving, small port turbo engine. The thing to limit is the delta (change in torque) and keep the effective compression ratio below the limit and to do a conservative tune on E85. Or do what I did and throw caution to the wind and flirt with the limit. Boost can be addictive.
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