MPORTANT!
Please remember that these figures are at the flywheel on a braked dyno in the UK. Do not compare them to American WHP figures. American figures are significantly higher due to not using braked dynos and dyno runs lasting only 4 or 5 seconds!
Unicorn Motor Developments have now acquired significant experience tuning the Audi S4/S5 B9 both on the road and dyno. The 3.0 V6 uses a single turbo mounted in the V of the engine, leading to two separate downpipes. The engine is coupled to an 8 speed ZF8HP automatic gearbox and quattro 4wd.
Please note that while we have grouped modifications into stages, this is purely to help with pricing, reflecting the R&D that goes into each tune. Each car is individually tuned in our dyno cell, with multiple data logging sessions carried out. From this data the car can be finely tuned both to the hardware and customers requirements. Enhanced overrun crackle can be applied in Dynamic mode on all tunes.
Standard power S4/S5 B9 power and torque curves
Officially the engine is rated at 354hp and 500Nm/369lbft of torque. We have found the stock car to give a slightly lumpy power delivery, with some torque spikes meaning the peak torque is higher at around 390lbft, but only for a short time.
Please understand that the level of tuning here is a step above all off the shelf tuned available. Not only in terms of outright pace but in the refinement. The software is tailored to each individual car, and any practical requirements you may have. We recommend Shell Vpower or Tesco 99 fuel, but it’s a good idea to bring the car on whatever fuel you will predominantly run. If you cannot for some reason run a higher octane fuel and only 95 octane is available then car is still safe to drive at motorway speeds, but we do not recommend high load for any extended period of time.
The 8HP gearbox contains a software torque limiter set to 550Nm. Attempting to tune the engine above 550Nm results in the Transmission Control Unit sending a torque reduction request to the Engine Control Unit. When this happens, torque is lowered by a combination of boost reduction and ignition timing reduction.
There are methods to fool the TCU into thinking the engine is actually producing less torque than in reality, allowing us to run more torque. However in the case of the B9, the TCU torque limitation is only slightly above the standard OEM torque figure. This means that any manipulation has to be quite extreme in order to run the 700+Nm that the engine is quite capable of. This manipulation leads to a less than satisfactory power delivery, both in terms of smoothness and throttle response.
As a result of this, Unicorn Motor Developments have developed a TCU tune. This increases the torque limiter which allows for a smooth calibration of the engine power and torque curves. In addition, auto upshifting in manual is disabled, the TCU will always engage 1st gear from a standstill. Shift speed is increased especially at low loads while maintaining smoothness. The auto upshift point is also reduced in order to better match the engine’s power band.
Unicorn engine software can only be applied in conjunction with TCU software and is not available separately. As well as the obvious increase in power and torque, the key feature of the Unicorn software is the incredibly smooth torque curve with no spikes. This leads to fast relaxed progress on the road, whether for effortless overtaking or more mundane city driving. Many thousands of miles have been logged on the road and dyno to ensure the best results. Both road and dyno testing is critical. Repeated dyno runs show exactly what part of the power curve can be improved while maintaining controlled conditions. We also reach speeds over double the national speed limit while on the dyno, and apply significantly more thermal load than would normally be achieved on the road, ensuring the software correctly reacts under highly stressed conditions.
Stage 1 software is designed for a completely standard car, and results in approx 425bhp and 475lbft/650Nm of torque on 99 octane fuel 100-200kph is dispatched in under 9.1 seconds.
Standard vs. Unicorn Stage 1 tuned power and torque curves
As well as the increase in peak power and torque, Unicorn software results in a significantly smoother power delivery than OEM, giving a wide plateau of torque without sudden changes.
All tuning is carried out through the vehicle’s OBD port, both engine and TCU.
The first limitation of the B9 platform is the intercooler. The OEM intercooler is rather small and results in high charge air temperatures resulting in a loss of power and efficiency.
Our Stage 1+ software is designed to be used with an uprated intercooler. Peak power on a single dyno run may only increase by 5-10bhp, however under sustained use (such as Autobahn) or in warmer weather, these gains are far more significant. Our software contains thermal trigger points not present in the OEM calibration which are far less likely to be triggered when an uprated intercooler is used.
Stage 2 software is for any car which has a sports and down pipe fitted, but applies to any amount of modifications that retain the stock turbo and run on pump fuel. Although not technically required, we highly recommend the use of an intercooler with stage 2 modifications and this should be fitted before any other mod. Other modifications recommended but not essential are as follows:
Performance filter or entire airbox upgrade.
Turbo Intake Pipe – from airbox outlet for turbo inlet.
Charge Pipe upgrade from intercooler outlet to throttle body.
Standard vs. Unicorn Stage 2 tuned power and torque curves
Power figures of 449bhp and 530lbft obtained with all stage 2 hardware modifications
Stage 3 software is for any car with a modified or larger turbocharger. As a rule, all modifications available for stage 2 should be installed. We have tuned many Stage 3 S4/S5 engines. On stock internals, we recommend keeping the torque under 600lbft/800Nm to give the engine its best chance of reliability. Although we do have cars running a little over 600bhp on the standard internals, we advise 530-540bhp as a good number. This results in an extremely capable car with a very wide power band of between 2500 and 7000rpm.
We recommend Littco hybrid turbos and the TTE810. The L610 will make 550bhp on pump fuel, and 590-600bhp with Water Meth. It will make 500lbft/750Nm by 2600rpm so has excellent spool. The TTE810 will produce 580+ on pump fuel and 600+ on water meth. For power levels above 580bhp we recommend an upgraded high pressure fuel pump.
Littco L610 turbo with and without water meth. Not that the higher power meth tune hs it’s torque capped.
Software Pricing:
Stage 1: £899 inc vat and dyno
Stage 1+ £949 inc. vat and dyno
Stage 2+ £ 999 inc vat and dyno
Stage 3 from £1499 inc vat and dyno