2020 VHTRacing 4AGE Dyno #4 - Airbox and latest updates

2020 3rd session which is 4th dyno session back in Europe with the 4AGE. 1St dyno session was 2019 with the old 2017 engine. At that time, we tested and compared the different fuels, VP MS 109 that we ran in the US against the German Aral Ultimate pump fuel (rules allow only pump fuel) and larger muffler and added exhaust catalyser which is also required in Europe. 2017 engine had at that time already quite a bit of running time, but It was a needed reference for the future updates to see what it did with pump fuel and catalyser per rules. Since then, we have rebuilt the engine over winter 2019 and tried improving the area under the curve between 7,000 to 10,000rpm range with several updates major being the new piston design. 2020 first dyno session was to see generally how the rebuilt engine performs with the increased compression ratio and advanced intake cam timing (deeper intake valve pockets on the new piston and dome raised). As expected, the curve was improved slightly, but peak power was reduced. We also tested injector position with the special mounting bracket to quickly validate different injector positions relative to the bell mouth. Once we found the best injector location and matching end of injection timing, we moved on to work on the airbox. First test with the airbox we focused to see what effect the airbox has general for the engine torque and if its tuning fits the required engine speed range. We also tested different length and type inlet tubes to the airbox. At this time, we unfortunately had issues with the electric throttle actuator motor and could not get a clear picture on the above 10,000 range as the throttle did not stay open at and above 10krpm. However, we saw which inlet tube works best from 7 to 10krpm. Next session was the one in this video with the completed intake airbox with inlet pipe and air filter box assembly. We have also done few other small adjustments, bigger exhaust collector entry angle, slightly reduced collector throat diameter and outlet taper which we tested on the last session and in the end, we ran 7bar fuel pressure on the last two sessions (+2bar to 2019). In the end the result is very promising, the engine has currently at 9000rpm which is roughly in the middle of the power band over 20hp more than 2019. The torque curve fits good with the gear ratios and the shifting point can be reduced slightly from 2nd gear upwards (10,900 to 10,600 at 5th gradually the higher the gear is). We have also learned and found out some interesting things on the process and believe there is still potential for further improvement on this little engine. In such highly developed package, you just can not do too many changes at once without validating them! The biggest improvement will in any case be the new quick change rear axle which will allow us to match the final ratio and thus top speed for each course quickly. We have 6 options to choose from top speed between 150 to 200km/h (6th gear 11,000rpm).

Видео 2020 VHTRacing 4AGE Dyno #4 - Airbox and latest updates канала VHTRacing