Silencer Substitute Pipes     Exhaust Systems are a popular area to think about upgrading for performance and longevity.   Silencer Substitute Pipes are an inexpensive starting point for most Jaguars, including some carburetor engined cars - the idea being to replace the most restrictive pair of silencers in the system with matching straight through stainless steel pipes.                 This is undoubtedly the most cost effective performance modification anyone can buy. The design of the exhaust system is dominated by considerations such as refinement and, of course, emissions legislation.  Many people think that the exhaust system on a modern Jaguar is a little too quiet for a car with high performance pretensions.  It is quite possible to obtain a reasonable increase in performance allied to a pleasing exhaust note without becoming an antisocial monster.  The simplest way of doing this is to replace the first silencer boxes below the rear seats with our SILENCER SUBSTITUTE PIPES for a gain of 15-20 b.h.p. The noise level is not excessive and they can be used on most cars with or without catalysts. per pair 5.3L per pair 6.0L Upgrade to TT System Mini Straight Through Boxes added: Stainless Steel Systems with all straight through silencers are an option we offer as a high quality replacement for a tired factory system, giving approximately the same performance as Silencer Substitute Pipes. Large Bore Exhaust System for Saloon and XJS         LARGE BORE SYSTEM - Saloons & XJS   Our LARGE BORE EXHAUST SYSTEM with all straight-through silencers removes virtually all the restriction from the system but in reality only gives about 5-10 b.h.p. more than the Silencer Substitute Pipes so is only really worth thinking about if the complete system is in need of renewal. TT Extractor System Our TT EXTRACTOR system is a tuned front section designed specifically to boost mid-range torque (which is what most people find useful). The original Y pipes below the standard manifolds (headers) are replaced by pairs of pipes of tuned length and diameter which merge just behind the transmission then feed through short adapters onto a pair of Silencer Substitute Pipes. From that point on the original system can be retained, renewed as a complete TT EXTRACTOR system, or replaced by a Large Bore Rear system for extra top end power but this option does tend to be noisier than some people would like for road use. The TT system significantly outperforms a Large Bore system so much so that fueling changes (included in the kit) are essential for it to work properly. The adapter pipes can be supplied with lambda sensor tappings but heated sensors must be used because of the distance from the engine. A wiring extension kit is included and we can supply heated lambda sensors as an extra.   TT HIGH TORQUE EXTRACTOR PIPES + Sil Sub Pipes + ECU mod. TT SYSTEM - Complete - Std rear section TT SYSTEM - Complete - Large bore rear section TT SYSTEM - Complete - V12 6L Saloon (XJ40 type)