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·Long before the CIS FI systems
Long before the CIS FI systems used on all Ferraris from 1980 to 89 came along there were very efficient FI systems widely in use. In fact the CIS Injection Systems were/are a huge step backwards as far as performance is concerned.
In days gone by (and agian starting in 95 for Ferrari) every Builder/Tuner worth a hoot used an Individual Runner (Intake) with it's own Butterfly and Injector to deliver the air and fuel needs. There were several ways to deliver the High Pressure Fuel, Mechaincal Timed Pump being the most familiar from FI, Can Am, the Famous Porsche 911 RS, etc. But in all cases the air was delivered via Seperate Intake Runner and Velocity Stack with it's own Butterfly. This set-up allowed unrestricked Air Flow at ALL RPM's and the metering of Fuel for Maximum Power.
Along came emmisions rules and Many Manufacturers like Ferrari & Porsche struggled to move into the modern world of Performance and Low Emmisions. Along came Bosch with a system (CIS) that Metered Fuel Flow Precisely while Restricting Air Flow to achieve an A?F Ratio that could be fed through a Catylitic Converter without causing fires. This was great on the emissions front but disaterous on the HP front. The 308 engine for example dropped from 235 HP with webers to a paltry 205 with CIS Injection. Not good said the racer types.
As technolgy advanced (mainly the speed of electronics) Ferrari once again in 95 returned to Individual Throttle Bodies on the 355. Horsepower thru better Flow was back on the map.
As many of you know an engine is simply a large Air Pump, it makes it's poower from pumping in Air, mixing with a combustable, exploding into power (conversion into heat) and exhausting the mix. It was found that even that waste product could in turn be used to provide additional power thru Turbo Charging. Not the subject of this thread, however. But that use of waste gas had drawbacks in the additional Heat & Stresses it created.
Now many are wondering how to increase the power of their stock Ferrari engines and an exhaust change has become common. Very few however are willing to address the full story of FLOW by removing the Restrictive Intake System dictated by the poor performing CIS System. It has long been known in tuning circles that removing the restrictive CIS System and replacing with Individual Throttle Bodies would truly deal with the Flow issues and unleash tremendous potential from the otherwise choked off base engine. The problem has been cost and the complicated series of changes neccesary coupled with the PR generated from Turbo Charger Kit sales people. As history has played out and the Turbo Kits have proved to be engine killing money pits that generally have questionable performance gains, the Indivisual Throttle Body Concept is gaining more popularity.
JRV
Long before the CIS FI systems used on all Ferraris from 1980 to 89 came along there were very efficient FI systems widely in use. In fact the CIS Injection Systems were/are a huge step backwards as far as performance is concerned.
In days gone by (and agian starting in 95 for Ferrari) every Builder/Tuner worth a hoot used an Individual Runner (Intake) with it's own Butterfly and Injector to deliver the air and fuel needs. There were several ways to deliver the High Pressure Fuel, Mechaincal Timed Pump being the most familiar from FI, Can Am, the Famous Porsche 911 RS, etc. But in all cases the air was delivered via Seperate Intake Runner and Velocity Stack with it's own Butterfly. This set-up allowed unrestricked Air Flow at ALL RPM's and the metering of Fuel for Maximum Power.
Along came emmisions rules and Many Manufacturers like Ferrari & Porsche struggled to move into the modern world of Performance and Low Emmisions. Along came Bosch with a system (CIS) that Metered Fuel Flow Precisely while Restricting Air Flow to achieve an A?F Ratio that could be fed through a Catylitic Converter without causing fires. This was great on the emissions front but disaterous on the HP front. The 308 engine for example dropped from 235 HP with webers to a paltry 205 with CIS Injection. Not good said the racer types.
As technolgy advanced (mainly the speed of electronics) Ferrari once again in 95 returned to Individual Throttle Bodies on the 355. Horsepower thru better Flow was back on the map.
As many of you know an engine is simply a large Air Pump, it makes it's poower from pumping in Air, mixing with a combustable, exploding into power (conversion into heat) and exhausting the mix. It was found that even that waste product could in turn be used to provide additional power thru Turbo Charging. Not the subject of this thread, however. But that use of waste gas had drawbacks in the additional Heat & Stresses it created.
Now many are wondering how to increase the power of their stock Ferrari engines and an exhaust change has become common. Very few however are willing to address the full story of FLOW by removing the Restrictive Intake System dictated by the poor performing CIS System. It has long been known in tuning circles that removing the restrictive CIS System and replacing with Individual Throttle Bodies would truly deal with the Flow issues and unleash tremendous potential from the otherwise choked off base engine. The problem has been cost and the complicated series of changes neccesary coupled with the PR generated from Turbo Charger Kit sales people. As history has played out and the Turbo Kits have proved to be engine killing money pits that generally have questionable performance gains, the Indivisual Throttle Body Concept is gaining more popularity.
JRV
