RX8 Servicing & Performance ProductsMazda RX8 Engine Tuning & Servicing Servicing for Mazda RX8s

Pettit Racing Built Engines - Mazda RX8

unsurpassed quality, top performance and outstanding reliability

In the past 20 years Pettit Racing has produced more than a thousand race and street rotary engines earning a worldwide reputation for unsurpassed quality, top performance and outstanding reliability. A reputation earned by having a passion for quality, superior attention to detail and Racing Championships to back it up.

Top Quality

So what makes Pettit Built Engines the best and how is that consistently achieved for over 1000 engines? Every Pettit Built Engine receives 8 quality control inspections; first the "rejection" inspection identifies all the failed and unusable parts from the chosen core or your old engine, these failed parts tell a story and this valuable information is very important because determining the cause or causes of failure can pinpoint existing problems so they can be corrected before they cause damage to the new engine. This is just another way we try to insure that your Pettit Built engine will have performance and longevity beyond expectations.

Next even brand new parts are carefully inspected and approved for each and every engine. Then all modifications, porting, machining, blueprinting and custom work are completed and inspection #3 is performed. The parts then receive a high temperature detergent bath and high pressure rinse by a 10hp cleaning machine and inspection #4 is performed. Then on to preassembly and inspection #5, to pass the preassembly inspection a 12-18 micron finish is required on all critical surfaces.

To consistently achieve these high standards, Pettit has developed several proprietary methods for machine and hand finishing of all critical surfaces, just one more reason Pettit Built Engines are considered by many to be the best. Next is Inspection #6, during this inspection the oil galleys, internal passages and all mating surfaces get a final inspection and special protective finishes are applied to the iron and aluminum parts. The parts are now ready for the engine (clean) room, there inspection #7 is performed as all critical openings are caped or sealed and made ready for final assembly. Finally during the assembly process we perform one last inspection for a total of 8 quality control inspections.

On top of all the inspections and paying close attention to every detail we only use genuine Mazda Parts, then every engine is personally assembled by Cam Worth, that's right for over 20 years he personally assembles every engine ever sold by Pettit Racing as well as countless engines for numerous race teams, all the R&D and race engines for Pettit projects and many special engines for magazines, project cars, boats and marine use, prototype and experimental multi-fuel engines, the new Diasio Renesis powered sports racers, the new X Board rotary powered surf boards and most recently AXIO 1 rotor kart engines.


Our standard street port is the right choice for both naturally aspirated and forced induction Renesis setups. Our modifications improve efficiency and flow with out major changes in port timing, benefits include more power delivered through all the rpm ranges as well as better fuel economy and improved longevity, besides our porting and blueprinting every Renesis engine receives special machining to improve coolant flow around the exhaust ports and reduce surface protrusion around the leading spark plugs, these modifications are a must do for turbocharged Renesis Engines.

Horse Power

The naturally aspirated Pettit Built Renesis when properly tuned with ambient temps around 70-80F, using a header and open exhaust will produce 245+hp or 210whp @ 8800 rpm. The same Pettit Built Renesis with our forced induction system, (supercharger) running 8-10 psi boost and maintaining charge temperature of less than 135F and again properly tuned w/ a header and open exhaust can produce 365+ hp or 330whp @ 8400 rpm.

With Turbo charging @ 12-14 psi/boost and maintaining a charge temperature of <125F with a .8:1 or less backpressure ratio is capable of producing 200 hp / rotor, or 400 hp, sure more boost makes more power but then other factors like material strength and management errors become more critical and these variables can lead to unexpected failures.

Engine Longevity

Engine Life is totally dependent on proper care and the best balance of performance and longevity is achieved by following our recommendations page. The basics are warm it up easy, keep the oil clean, use Protek fuel lubricant additive and good quality fuel. These simple techniques have proven to work for many customers worldwide and many have reported their Pettit Built engines still performing well with over 10 years of use.


Renesis exhaust and intake port flow path modifications (some pictured above) i.e. radius machining, blueprinting, porting, polishing and our modifications that improve coolant flow around the exhaust ports, all help to minimize heat concentration on the side housing surface at the outer edge of the exhaust ports, this is proving to be a common point of failure especially with turbocharged Renesis engines. These modifications not only add power but make a significant improvement in reliability; and cooler operating temperatures will always benefit performance and longevity.



   Pettit Built Renesis

  • Improved power

  • Better longevity

  • Better performance

Combine a Pettit built Renesis with our ANP "All Natural Power" performance kit  for a fantastic NA RX8.




Pettit Racing Built Engine - RX8

£TBC + VAT *

Return your old core for a rebate

£TBC + VAT *

Buy from Pettit Racing here



* Fitting & shipping charged as extra. Prices subject to change and some items may be limited to stock on hand.

Whilst every effort is made to display prices as accurately as possible, Pettit UK reserves the right to refuse to honour any price that has been displayed in error.

Mazda RX8 Performance Parts & Servicing, London.

Welcome to Pettit Racing

Rotary specalists for over 25 years