LS3 vs 5.0 yote? motor only comparison.

[Firefighter]

So the HP is similar but the TQ is down and it comes on late compared to an LS3...

[thunderkyss]

Does anyone build a package that will allow you to reliably spin an LS motor to 7500 rpm?

[Norm Peterson]

Originally Posted by Firefighter

So the HP is similar but the TQ is down and it comes on late compared to an LS3...

Mostly what that means is you have to drive it in the higher rev ranges to get comparable performance (and as a downstream consequence the transmission gear spacing for such an engine should probably be tighter to better keep you in it under a wider range of situations). Independently variable exhaust vs intake timing helps by widening the powerband a bit, but this won't be enough to fully cover for the difference in displacement.


Norm

[Firefighter]

Originally Posted by thunderkyss

Does anyone build a package that will allow you to reliably spin an LS motor to 7500 rpm?

A balanced forged bottom end and a properly set up valvetrain that's doable with an LS motor no problem. Hell the SBC can do even do that. If you have enough money a BBC can do it too.

[RyanR3KC]

Originally Posted by TexasChile

The Ford GT 500 has a larger motor than the 5.0 and it fits in the Mustang just fine and it produces a lot more HP than the ZL1. I think your statements above are exaggerated--the weight, size, center of gravity, etc. are not as big a difference as you make them out to be. What little difference there is in those factors is far outweighed by the pure HP advantage per cubic inch of the overhead cam design.

They have different superchargers. You didn't take that into account.

[Norm Peterson]

Originally Posted by RyanR3KC

They have different superchargers. You didn't take that into account.

I think what Tex was mainly getting at was that even though the 5.8L Trinity engine is larger still than the 5.0 (which itself is both wider and taller than a 460 pushrod motor), it still fits into the chassis - without the shock tower tweaks Ford used back with the 1st gen Mustangs to fit 390's and up into them.

Different superchargers go either to the ability (or not) of fitting it under a stockish hoodline or the company's commitment to making the most power with the fewest/smallest downsides. Your choice, but working a smaller blower harder generally heats up the intake air more, with adverse effects on tuning strategies. This isn't coming from a brand favoritism point of view, because I'd choose a 5.0, GT350, 1LE, or Z/28 over either of their supercharged stablemates. Every time.


Norm