Compression problems

[Killrob]

Definitely a bug, both cases should have the same result. We need to dig further ;(

[Bullets]

ok
Thanks for your attention Rob

[pHanta]

I'm bumping this thread as I suffer from a similar problem that only seem to happen to me on the "flying debris" and the "spinning faster" scenarios. I am on the public build 1323 but I did start these missions in the build 1198 (not sure if that's a factor). Everytime I improve my score and I make another test, the octane jumps up (for example, in spinning faster, it goes from 90.8 to 92.1), even if I didn't touch anything. If I quit and reload the mission, it drops back to normal, until I improve the score again and make tests after that. However, I found out something weird when I looked back at the engine parts in "spinning faster" : for some reason, the short cast header type has its max power value shrunk from 188 hp to 108! And all the other header types had their max power value changed as well. If I put long tubular headers, the octane goes back to it's previous value, but the score is lower due to the increased cost.
Could it be a glitch related to the bore value ?

EDIT : I just made another weird discovery in the flying debris mission : if I change the stroke value after the octane jump and I make another test, it drops back to normal. However, if I make other tests after that, the octane jumps back up again (unless I change again the stroke). So there must be something going on with the displacement...

[NormanVauxhall]

I can confirm this was happening to me too. (once you set a new record, the engine go "berserk") I forgot to pivotal it.

[23dutch45man]

I have managed to figure out what happened in the Muscle Car mania scenario and the Da-Car scenario with my v8 engines losing power. I was losing power in both cases because the push rods and the direct acting valve headers were suffering from some bug which involved the calculations of valve float. In this case it was occuring starting around 3200-3500 rpm, they were turning yellow/orange/red depending on the rmp the engine was running. Whenever the bug occured, it didn't affect the reliability of the engine for some reason.

If switching from flatplane to crossplane and back again, the power would be normal, until I start fiddling with my engine once again.

[Killrob]

Can you upload an engine where that happens and give us the steps to reproduce this behavior?

[23dutch45man]

I have managed to get across this bug once more, but strangely, it might not be a bug in the valve headers, but in the long tubular exhaust pipes / exhaust pipes from the v8 flatplane. The amount of power they can handle seems to drop from 400 kW+ to a mere 170kW+ for no reason.

The bug does not occur always, but if you change the ignition time and the amount of fuel injected, it will likely occur. Changing compression can also work.