Dyno data analysis
Okay so I have the data from the Toovey engine dyno run some years back, and I now have a second set of data points from the rolling session at Northampton Motorsport and the numbers do have some correlation (as one would expect).
There are some data gaps in both sources of data, namely that on the engine dyno I only had data for 3500 RPM and above and on the Northampton Motorsport data tick-over to 6000 rpm (limited due to the previously posted vibration issues).
In the below image we see a screen capture of the two sets of data for the BHP. We can see in the purple data set (Northampton Motorsport) that the power line is smoothed out and the loss of power previously seen around 4350rpm is eliminated. Secondly the line starts to flatten off around 6000rpm. This is suggested to be a result of the vibration issues (severe) absorbing energy, and for safety reasons the car was backed off at this point and not taken to higher RPM’s.
Once I get that vibration issue solved I hope to map the rest of the rev range and see a continuation of the power line that matches the Toovey engine dyno run (shown in a Salmon Colour).
The second graph is the torque values from the same two dyno runs, again around the 4250 mark the engine dyno saw a drop in value (on carburettors at that point) and now in the new dyno run we see a much smoother and constant torque value. Again this tails off quickly as we hit the 6000rpm area as throttle was lifted in order to back out for the vibration issues.
Its was important to back out at the time as a failure in the transmission, prop or axle will have resulted in demolishing of the car, as at 6000 rom the car was travelling at over 100 mph on the rollers. 7200 rpm (my red line) in fourth is another 25mph faster, so caution was the name of the game.