Yowzer

I wonder when Lifans will be back in stock

Here's some science or something. Pretty basic article but meh. https://www.onallcylinders.com/2015/10/30/header-theory-part-1-looking-at-the-science-behind-exhaust-header-tuning/ I did read a very in depth article ages ago regarding this on old F1 engines, but it was high level stuff and I wasn't all the sober at the time.

Oh @Roman I was pondering your exhaust tuning question re maf sensor, and it occurred that it may not be so simple. I don't know the dynamics of exhaust pulse tuning well enough to know when the pulse is actually supposed to be timed for maximum results. For example, if you have a low pressure pulse hitting the ex valve as it opens, you'd aid cylinder extraction and reduce pumping losses, but this wouldn't have any effect on the intake. However you could also have this pulse during overlap and aid scavenging, which potentially would show on the maf Or if you have a high pressure pulse hit the valves during scavenging to push over-excited intake charge back in the cylinder, much like a twostroke In short, I have no idea and I'm just thinking out loud. Make some graphs and report back

I'm going to commit to this this time. I have a shit RV50, I'm gonna shove a Lifan up it and I'm gonna be there. Or I wont.

I love replacing snapped wheel studs

Yeah iit's not 2.6kw electric, hooks up to the cooling system like the factory heater core. For the price it'd be better than nothing!

Same same You're launching under suspension compression, but once the front ejects off the ramp the rear wants to do the same due to weight transfer (coz front is now weightless) but if more rebound dampening sucks, build a ramp where the suspension can relax before launch so it doesn't kick you out. I dunno if there's a way to solve it suspension-wise, but I love your work so I am keen to see it!

Sweeet! You're gonna need less rebound on the rear, or re-engineer your ramp so the springs decompress before launching to stop the rear kicking it into rotation

Seems like a waste, they should be swapping the whole engine.

I see no reason why you couldn't, people have repurposed the Honda ECUs for other jobs with great success so it'd be very much the same.

Lol I built this stupid thing years ago with a pile of modifications, but the HDD that had all the info on it died. Yay backtracing my mess.

Yup that's the sucker

I have plenty of ECUs, maybe I'll chuck the MS in the factory case to keep the plugs. Edit: actually that would be a pain as I still need a board to attach the plug to. And unsoldering it would suck.

Yeah I was pretty damn tempted to get one, but saw they were discontinued last night too. Ruined that fun Yeah this plug sucks. Ah well, a tonne of hot glue will keep everything together

OK I'm gonna go build a loom to connect my MS2 to a 5MGE now

Best get those cams then. I wanna see more graphs! And then you can play with getting an NA engine over 100% VE

Yeah I have no idea how that analogy works. Maybe it's relevant to 4Ks? If you want me to be more specific, which I didn't think I had to as it seemed pretty obvious, maximize the mass of air in the cylinder

The amount of air you'd lose to scavenging would be pretty fuck all, wouldn't it? If anything it's beneficial as it's clearing all the exhaust out before it fills again? Pretty sure that's how it works

You'll see that on your 02 sensor NA engines don't have that problem as much as boosted engines, as excessive overlap creates a reduction in manifold vacuum which = less airflow. Sort of. At low RPM anyway

Your airflow puts a cap on how much power you can make. No point tuning for maximum power before you have the maximum available air entering the cylinder.

You need a longer rod m8 And more komprezzions

Back on the subject of improving efficiency, has anyone considered converting to Miller cycle? https://www.researchgate.net/publication/322864331_Effects_of_applying_a_Miller_cycle_with_split_injection_on_engine_performance_and_knock_resistance_in_a_downsized_gasoline_engine

If you're looking for 10/10ths you can probably justify the $200hr for 10 hours of dyno time. In Romans case, chasing a massive torque hole will still be visible with a % or two of inaccuracies.

Record RPM, chuck car in 3rd and pin it until redline. A differential on the RPM graph will give you engine acceleration over time, which should directly match engine torque. Chuck another little bit of math on top and you'll have a representation of power (slightly inaccurate due to wind resistance at higher speeds, but fine for comparative purposes) This won't give any torque or power figures, it'll just give you the plot.

The dyno measures a change in acceleration at the wheels, but you can measure the exact same change at the engine directly. You just have less control over the variables on a road. Unless you have a braked dyno which is a different story, that is far better for tuning fuel efficiency since you can hold the engine at a constant RPM while playing with numbers, which much harder to do on a road tune due to running out of road.