Sit in them before you buy them, your body's frame might be larger than the seat's frame... Picking a seat depends on your intended use for the seat and your body shape. Side mount seats offer optimal design for high performance and competition driving. For optimal performance, the Recaro SPG are phenomenal. The ergonomics and support are so superior, it even feels comfortable for long drives. The SPG however has high bolsters and is designed for smaller drivers (below 35" waist). The Sparco REV is another good pick for slightly larger drivers. It has slightly smaller frontal bottom bolstering for easier exit. These seats are compatible with stock belts as well as 4, 5, 6-pt belts.
The Sparco Speed offers a high quality seat for a reasonable price. Finally, for street use, the Sparco Torino, Milano, and Roadster offer supportive and stylish designs. These seats are compatible with stock belts as well as 4-pt belts (Roadster & street seats will need to be modified for use with 5/6th point belts).
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Side Mount Fixed Position
Recaro SPG: the ultimate streetable race bucket. Most ergonomic, comfortable, lightweight, and supportive seat. Advanced design with excellent bolstering allows maximum comfort making the SPG line one of the most popular in professional motorsports. Factory seat belt & 4-6/pt harness compatible. Black only. S-M sized drivers.
Side Mount Fixed Position
Sparco REV: Sparcos revolution in the field of racing seats, used by many official teams (Ford, Alfa Romeo, Peugeot, Nissan, Renault and many others) in World Rally Championships and important Touring Car Championships. Manufactured with sophisticated production techniques and revolutionary materials which guarantee it to be light-weight, comfortable, and strong.
http://www.sparcousa.com/pseats_comp.asp?id=84Side Mount Fixed Position
Sparco Roadster: An evolution of our world famous competition seats, this seat is designed for highway use (not recommended for competition purposes) and designed to be used in high performance sports cars. Provides maximum lateral support without being difficult to get in and out the car. The shell is made in fiberglass.
http://www.sparcousa.com/pseats_street.asp?id=97Bottom Mount Fixed Position
Sparco Speed: The Speed is an evolution of the world famous "Sprint" competition seat, which is one of the most popular seats in Sparco's line. A joint technical partnership with Pirelli has developed a new internal support system that offers improved comfort and control. In addition, the Speed has adopted the perforated abrasion resistant inserts on the side bolsters that are found on the Milano and Torino seats. This system protects the seat in high wear areas. The Speed also features the high density injection molded memory foam found in the Torino and Milano. The modified design and new features have all been incorporated to produce Sparco's most affordable and stylish seat. Not recommended for drivers over 6' tall.
http://www.sparcousa.com/pseats_street.asp?id=316Bottom Mount Reclinable
Sparco Torino: One of the most advanced adjustable sport seats ever manufactured by Sparco. Anatomic, extremely comfortable and in a refined and modern design. Back rest can be reclined to the millimeter, but features the exclusive QTS Technology (quick tilt system) technology for rapid return to the upright position. It also features a revolutionary contoured injection molded memory foam. Touring car inspired g-force absorbing side bolsters. Perforated abrasion resistant inserts, and a micro-fine recline mechanism. Not recommended for drivers over 6' tall.
http://www.sparcousa.com/pseats_street.asp?id=95 Bottom Mount Reclinable
Sparco Milano: The most advanced adjustable sport seats ever manufactured by Sparco. Anatomic, extremely comfortable and in a refined and modern design. Back rest can be reclined to the millimeter, but features the exclusive QTS Technology (quick tilt system) technology for rapid return to the upright position. It also features a revolutionary contoured injection molded memory foam. Touring car inspired g-force absorbing side bolsters. Perforated abrasion resistant inserts, and a micro-fine recline mechanism. This seat also features a lumbar adjustment system to ensure proper ergonomics and ultimate comfort while driving at all times. Not recommended for drivers over 6' tall.
http://www.sparcousa.com/pseats_street.asp?id=96