LQ4 Power

[lionelhutz]

I guess everyone who is swapping an LS engine into their rides to go faster is doing it wrong...

The torque curve tells you how fast you accelerate when you have the drivetrain but the HP curve tells you how fast you could accelerate when you are picking the drivetrain. I guess if you insist on running a LS engine with a drivetrain optimized for a low HP low rpm small-block then you wouldn't see the gains the LS engine can give you.

I've really only seen curves where an older small-block had more torque below about 2500rpm but really fell off above 5k rpm where a similar LS engine held the torque until well over 6k rpm. Around 2.5-5k the torque curves are similar. I would attribute the difference to shorter intake and/or exhaust runners used on the LS engines. The LS engine is simply built to produce it's power at a higher rpm. If you insist on running <2.5k towing then the small-block could have an advantage. But, gear the LS vehicle to hold another 1000rpm or so at the same road speed and it would kill the small-block. You could also put a long runner intake and headers on the LS and it would likely match the small block power curve.

My parents take a trailer to Florida every year and their '06 5.3L LS truck used about a 1/3 less fuel than their old '90 TBI truck and pulls better too.

I'd put this LQ4 into my car over any small-block I've managed to build.