Audi RS4 / RS5 B8 V8 4.2L FSI (CFSA)
AUDI RS4 (8K) RS5 (8T3) 2010-2015 ENGINE CODES – CFSA
STOCK POWER – 450PS STOCK TORQUE – 430NM
The RS4 and RS5 B8 Introduced in 2012, retained the same 4.2-litre V8 from the B7, but output increased to 450ps. Torque remained at 317lb-ft, but crucially, it arrived 1,500rpm sooner – at 4,000rpm – and was sustained to 6,000rpm
Engine Specs:
- Type: 4.2 L V8 FSI (Naturally Aspirated, Direct Injection)
- Power: 450 PS (444 hp / 331 kW) @ 8,250 rpm
- Torque: 430 Nm (317 lb-ft) @ 4,000–6,000 rpm
- Redline: 8,500 rpm
- Transmission: 7-speed dual-clutch S-tronic only (no manual option)
Carbon Build-Up on Intake Valves
The B8 has Advanced FSI with improved injector design and spray pattern, still direct only (no port injection) but still suffers from Carbon Build up:
Cause: The CFSA uses the same type of direct fuel injection (FSI) as the BNS engine of the RS4 B7, which sprays fuel directly into the combustion chamber instead of over the intake valves. Without fuel washing over the valves, oil vapor and blow-by gases from the PCV system deposit carbon on the intake ports and valves – we can carbon clean using our walnut blasting machine restoring the engine to its original performance – then adding Stage 2 parts upgrade and tune for more power and torque.
Symptoms:
- Loss of power (often 20–40 hp or more)
- Rough idle or misfires
- Hesitation under load
- Poor fuel economy
STAGE 2 Package Details:
Power Figures obtained are depending on the carbon build up inside the engine components.
We would require a non refundable deposit of £150 to secure the booking. We would require the car to be with us for 3-5 working days to carry out the work. Please make sure your car arrives with at least half a tank of fuel and is always run on the best fuel, which in the UK is Tesco 99
Injectors are becoming a common issue on the B7/B8 models, we do recommend having them removed and replaced for the latest revision, especially if the car is above 80k miles. We do also offer testing and cleaning. Please note that we have come across injectors being seized in place, this could lead to further time being spent on removal as well as the injector(s) having to be replaced – for more information about injector cleaning click here.
When checking and cleaning Injectors they should always be flow matched to be within 1% of each other, depending on your results will depend on if we can re-use or if we have to replace them. If you would like this to be priced up please let us know so we can adjust your estimate to suit.
If the intakes are built up with carbon we would notice when we dyno the car by the airflow we would recommend Carbon cleaning.
Please read our frequently asked questions at the bottom of this page to see if it answers any other questions you may have.
Frequently Asked Questions
Please check the below questions to see if it answers your query before ringing the office
Bookings
We require non refundable deposits for all bookings made, if you’re more than half an hour late, try to rearrange within 48 hours or do not show we will keep the deposit, if you are wanting to re book then another deposit will need to be taken.
We also ask that all invoices are paid by BACS before collection.
Engine related FAQ
All tuned Vehicles should be ran on Audi long-life 5W40 oil.
All 2.0L 2.5L and 4L engines should be ran on NGK race plugs once tuned.
Please let us know if service work needs to be added to your estimate
Service Intervals:
- Oil and filter change once a year or every 10k
- Major engine service every 2 years or every 20k
- Transmission (gearbox, haldex, diffs, transfer box) should be done every 3-4 years, every 35k
- Depending on how the car is driven, if the car is driven hard/ abused etc then these intervals should be cut in half.
Fuel
Please make sure your car arrives with at least half a tank of fuel and is always run on the best fuel, either Tesco 99 Momentum or Shell Vpower
Coilpacks
Please be aware that old coilpacks can fail when running more power, causing a misfire, please make sure you have newest revision coilpacks before booking in, or let us know and we can add these to the estimate and replace on the day.
Labour rates
Our standard labour rate is charged at £119+vat unless the vehicle is tuned by ourselves and we are supplying and fitting all parts then it is discounted to £99.50+Vat
