how can a 3.5 be more powerful than the 4.0 we have in the same weight body?

http://www.muscularmustangs.com/2005...7newengine.php

 

the answer is in the article

"The upper end of this engine consists of DOHC (dual over head cam) aluminum cylinder heads which incorporate centrally located spark plugs, and combustion chambers resulting in a 10.3:1 compression ratio. "The 3.5-liter V-6 uses a compact, lightweight dual-overhead cam valvetrain for peak power capability and smooth operation at high RPMs. The engine also incorporates intake variable cam timing (iVCT) to optimize valve timing for a smooth idle, optimal part-load driving and an impressively broad torque curve with good power. The iVCT system uses a hydraulically actuated spool valve that can rotate the intake camshafts up to 40 degrees within a half-second."

Valvetrain DAMB, 4 valves per cylinder, intake variable camshaft timing

Longer stroke, Higher Compression, more valves and Variable Valve Timing. The smaller bore cancels out the increase in TQ you would normally see when increasing the stroke on a similar engine.

 

well why dont they apply the same components and principles into the 4.0 and get even more power? it just dosent make sence why they'd switch to a smaller engine like they did with the 5.0's

 

Economics. 4.0L was already being used in the Explorer and Rangers so to keep costs under 25-30K for a V6 they went with what was already available.

Same can be said for Nissan/Infinity heavy use of their existing 3.5L motor. They could've engineered a new engine for the 350Z (that output 350hp) but then it would bump it to 40K or more or make infinity cost another 5-10k.

 

also take a look at the rotary engines...amazingly small for the power they give off

 

At least the 3.5L will be built in America! [sm=americanasmiley.gif]