[NESW20]

Originally Posted by ichitaka05

Wait, wait, wait... you're comparing Si to base model Impreza? Am I the only one think that's not the fair comparison. Base Impreza is only Impreza with NA engine. While Civic has ridiculous amount of NA engine and model to choose from. Specially you're using top base Civic Si (in US), while you're using lowest base for Impreza? Because it's NA?

Also you have forgotten about the drive train. If that KA20 engine was put to AWD drive train, do you think it'll dyno same amount of hp & tq? My guess, I don't think so.

Honda has fan for NA engine, but Subaru fan is pure Boxer Turbo engine. Took em over 10 year to finally get extra 5hp/3tq and still running SOHC on current 2.5L engine (EJ253) on NA, while took em 3 yrs to get 20hp/26tq on Turbo with DOHC (EJ257). Subaru don't give a damn about NA Boxer engine (no offense to Subie fan here). They put their whole research into TURBO boxer engine. Cuz they know that, they can't make good NA boxer engine like Porsche and no one is stupid enough to buy $30k plus NA Impreza while you can buy Turbo ver for cheaper.

i'm comparing their ENGINES. both are small displacement 4 cylinder engines currently available on the market. i was showing that Subaru n/a 4 cylinders don't necessarily have more "torque/L" than other engines. BHP is "brake horsepower" as measure at the crankshaft (on an engine dyno, with the engine not installed in any car, only on a stand in a shop/lab). you are thinking of WHP or "wheel horsepower" as measured by chassis dynomometers (the rollers that cars drive on). they are not the same. all car manufacturers list BHP in their spec sheets.

Originally Posted by ichitaka05

No, it's totally different. 2wd bhp vs awd bhp. I need to look for thread on some dude change his Impreza Wagon into FR with stock NA engine and when he dyno it, hp & tq was higher.

So it's okay to use top model Honda engine vs low model Subaru engine? That's more like Apples to Oranges here. Bring the current low model AWD/4WD NA Honda i4 engine (in US) vs current low model AWD NA Subaru H4 engine (in US) and compare the hp/l & tq/l. That should be Apple to Apple.

2wd and awd whp are different. bhp is bhp is bhp is bhp is bhp. the reason your example of the FR impreza had a higher HP rating after it was converted was because there was less drivetrain loss, so more of the engine's BHP was converted into WHP.

the only reason i chose the n/a 2.5L subaru engine is because they don't offer a high-output version here in the US, except the 3.6L H6. it has HP ratings of 256hp and 247ft.lbs of torque. that's 71hp/L and 68.6ft.lbs/L. that's their "high end" n/a engine here in the US.

but just to make you happy, here's the breakdown for honda's base level Civic engine: 1.8L I4. 140hp and 128ft.lbs of torque. when you do the math, it's 77.8hp/L and 71.1ft.lbs/L. Subaru still falls behind in the specific power and torque output.

i hope all of this makes sense for you. drivetrain has NOTHING to do with BHP, only WHP. you are getting the two confused.

-Mike