I was quite surprised this wasn't already on-site. Comments and criticism is always welcome.
http://www.smogon.com/dp/pokemon/heatran
[SET]
name: Life Orb
move 1: Fire Blast
move 2: Earth Power
move 3: Explosion
move 4: Hidden Power Grass / Hidden Power Electric / Taunt
item: Life Orb
nature: Naive
evs: 4 Atk / 252 SpA / 252 Spe
[SET COMMENTS]
<p>Heatran is a great candidate for utilizing Life Orb to further boost its already massive Special Attack stat. This set allows Heatran to act as a fluent sweeper without the restrictions that Choice Scarf and Choice Specs hold on it, while maintaining the power needed to achieve certain KOs, that Heatran would otherwise miss without the boost Life Orb gives.</p>
<p>Fire Blast is Heatran's STAB move for this set, causing decent amounts of damage on common switch-ins such as Gyarados and Salamence, while also ruining Scizor, Jirachi, and Celebi. Earth Power complements Fire Blast by hitting other opposing Heatran that may switch-in predicting Fire Blast and looking for a Flash Fire boost, and is also necessary for removing other common Fire-type Pokémon who may otherwise try to cushion Fire Blast. Explosion is amazingly powerful, and can guarantee an OHKO on a 0 HP / 252 Def Bold Blissey after Stealth Rock damage, which may be useful to open a sweep for another Pokémon in your team. Hidden Power is optional depending on what you wish to eliminate out of Gyarados, or Swampert. However, Taunt is a great move as it stops Pokémon such as Blissey, and Cresselia from inflicting horrible status moves which could otherwise effect Heatran's sweeping efficiency. One could also consider Dragon Pulse as it is useful for Kingdra, and helps against Salamence, Flygon, and Dragonite.</p>
<p>Expert Belt along with Heatran's attacks will bluff Choice Scarf, often causing the opponent to assume that Heatran is holding a Choice Scarf and send in something like Gyarados or Swampert to take the opportunity to set up, but will fall to one of Heatran's other unnoticed attacks. A Naive nature is recommended as it boosts Speed without hindering Heatran's Special Attack, and Attack. The EVs maximizes Heatran's Special Attack stat for maximum damage inflicted upon foes, and allows Heatran to outspeed all neutral base 85 Pokémon.</p>
http://www.smogon.com/dp/pokemon/heatran

[SET]
name: Life Orb
move 1: Fire Blast
move 2: Earth Power
move 3: Explosion
move 4: Hidden Power Grass / Hidden Power Electric / Taunt
item: Life Orb
nature: Naive
evs: 4 Atk / 252 SpA / 252 Spe
[SET COMMENTS]
<p>Heatran is a great candidate for utilizing Life Orb to further boost its already massive Special Attack stat. This set allows Heatran to act as a fluent sweeper without the restrictions that Choice Scarf and Choice Specs hold on it, while maintaining the power needed to achieve certain KOs, that Heatran would otherwise miss without the boost Life Orb gives.</p>
<p>Fire Blast is Heatran's STAB move for this set, causing decent amounts of damage on common switch-ins such as Gyarados and Salamence, while also ruining Scizor, Jirachi, and Celebi. Earth Power complements Fire Blast by hitting other opposing Heatran that may switch-in predicting Fire Blast and looking for a Flash Fire boost, and is also necessary for removing other common Fire-type Pokémon who may otherwise try to cushion Fire Blast. Explosion is amazingly powerful, and can guarantee an OHKO on a 0 HP / 252 Def Bold Blissey after Stealth Rock damage, which may be useful to open a sweep for another Pokémon in your team. Hidden Power is optional depending on what you wish to eliminate out of Gyarados, or Swampert. However, Taunt is a great move as it stops Pokémon such as Blissey, and Cresselia from inflicting horrible status moves which could otherwise effect Heatran's sweeping efficiency. One could also consider Dragon Pulse as it is useful for Kingdra, and helps against Salamence, Flygon, and Dragonite.</p>
<p>Expert Belt along with Heatran's attacks will bluff Choice Scarf, often causing the opponent to assume that Heatran is holding a Choice Scarf and send in something like Gyarados or Swampert to take the opportunity to set up, but will fall to one of Heatran's other unnoticed attacks. A Naive nature is recommended as it boosts Speed without hindering Heatran's Special Attack, and Attack. The EVs maximizes Heatran's Special Attack stat for maximum damage inflicted upon foes, and allows Heatran to outspeed all neutral base 85 Pokémon.</p>