ScienceofSpeed Twin Turbocharger System - NSX, 1991-05


The ScienceofSpeed Twin Turbocharger System is the ultimate forced induction system for the NSX proving that high performance can include high reliability with a factory quality design. Now available as a Tuner kit, or as a complete kit with engine management, fuel system, and accessories!

factory quality performance
The system stands alone in design and construction to best represent the most factory approach to the design and execution of a turbocharger system for the V6 powered NSX. Unlike single turbocharger systems which merge the twin cylinder banks into one manifold, the ScienceofSpeed Twin Turbo System is designed similar to a factory style turbocharger designs for V engines - with one turbocharger per cylinder bank. This allows the turbocharger to be optimally placed as close as possible to the engine's exhaust ports for best transient boost response, reducing the "boost lag" found with other turbocharger systems. In addition, separating the cylinder banks eliminates exhaust reversion seen in merged single turbo systems increasing turbocharger response and decreasing backpressure. The smaller turbochargers are optimized for low and mid-range power, yet collectively allow a significant amount of exhaust volume to pass at high RPM to increase top-end power yield.

factory quality fitment and reliability
In addition to performance, a significant emphasis was placed on designing a system that does not require permanent modification to the vehicle and emphasizes reliable performance. Heavy wall stainless steel manifolds manufactured by ScienceofSpeed optimize turbocharger placement and fits the turbochargers within the confines of the NSX engine bay. This placement mounts the turbochargers above the oil pan and eliminates the need to run external scavenge pumps - an important advantage compared to other single turbocharger systems which expose the engine's oil system to the potential unreliability of an electric pump. In addition, the turbochargers use reliable internal wastegates which reduce complexity, increase reliability, and promote a quiet livable exhaust sound. The design and layout is stealthy and mostly hidden. The engine bay looks mostly stock with the exception of the aluminum charge pipe - which may be covered for the ultimate sleeper presentation.

no compromise material and craftsmanship quality
An exceptional amount of emphasis was placed on quality to yield not only a fantastic looking system, but also one that is built to last. The turbocharger exhaust manifolds are fabricated from CNC machined stainless steel flanges for a precision fit with forged stainless steel tubular exhaust manifolds that have been designed as support members as well as to provide high velocity exhaust pulses to the turbocharger for maximum performance. The forged stainless steel tubular manifolds allow maximum thermal energy from the engine to transfer to the turbocharger turbines for best throttle response. The exhaust manifolds and turbocharger down pipes are all TIG back-purge gas welded for the most durable high quality construction. Several components have been custom designed by ScienceofSpeed - and the proof is in the details. An example is the custom machined NSX cylinder head adaptor fittings that efficiently feed the turbochargers with oil supply. You do not need to tee into the factory oil housing with fittings that do not fit and chance cracking the housing from vibration like used on other systems.

a powerfully flexible design

The ScienceofSpeed Twin Turbo System provides the most expandable system available. The system's twin turbochargers can produce up to a 200 horsepower gain on the factory 3.0L or 3.2L engine with no modifications (approximately 470-490 horsepower at the engine) and 300-500+ horsepower gains (approximately 580-900 horsepower at the engine) with built strengthened engines. The use of twin turbochargers allows a significantly wide performance envelope. The system is ideal for a customer with a factory engine with goals of 400 horsepower all the way to a customer who is interested in expanding the factory engine with goals in excess of 900 horsepower!

This product is designed and intended for Racing Competition Only:

This product is not designed or intended for pollution controlled vehicles. In the United States, the use of this product is regulated by the Environmental Protection Agency under the Clean Air Act. Use of this product must be used in accordance with the Clean Air Act, and any other Federal, State, or Local mandated regulations. The use of this product must only be used on a vehicle in sanctioned competition events and may not be used on public roads, streets, or highways. A Vehicle Compliance Waiver is required for all products marked "Racing Competition Only".


All ScienceofSpeed Twin Turbocharger Systems include:

  • ScienceofSpeed modified twin GT25R (for factory engines) or GT28RS turbochargers (for modified engines): ball bearing, oil lubricated, water cooled
  • front & rear exhaust manifolds: CNC machined stainless steel flanges, forged stainless steel tubular TIG back-purged welded
  • front & rear turbocharger down pipes with separated wastegate dump tubes: stainless steel tubular TIG back-purged welded
  • liquid-air intercooler, heat exchanger, water pump, and reservoir
  • aluminum TIG welded intake charge tubes (4)
  • twin intake system with AEM Dry-Flow air filters
  • TIAL 50mm vent to atmosphere blow-off valve
  • high quality 4-ply silicone hose couplers, stainless steel smooth band clamps, and all required installation hardware
  • turbocharger water cooling installation kit
  • oil feed & oil drain installation kit with custom dual cylinder head feed fittings
  • 2000-05 NSX: includes additional accessories for retaining the factory air injection system

1991-94 Stage 2 (includes engine management & fuel system):

1995-05 Stage 2 (includes engine management & fuel system):


fuel system:

Note: All year ranges can be upgraded to Infinity 8 for an additional cost.

upgraded turbochargers:

The ScienceofSpeed Twin Turbocharger System includes either GT2560 (for factory engines) or GT2860 (for low compression engines). Higher capacity turbochargers are available for applications with built engines - call for details.

exhaust system requirements:

ScienceofSpeed Twin Turbocharger System - NSX, 1991-05



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