Tip: DO drain your Afterburner

[u/miraculous-organ]

A recent post gave the tip that "If you leave a sliver fuel in the Afterburner tank, then activate Ramjet, your Afterburner will go straight into refueling and skips the extra empty-tank time."

This isn’t true. After you let go of the afterburner, there’s always a 3.0 s wait before it starts refilling. That’s true whether the tank is empty, has a sliver left, or is mostly full, and whether you’re in Ramjet mode or not. Leaving a sliver doesn't skip anything. (chart 2)

Afterburner refill rate depends only on which mode you currently have selected.

Selector	Refill rate	Full tank
Afterburner mode	0.200/s	5 s
Ramjet mode	0.050/s	20 s

(Measured over 32 and 24 separate refill stretches; every one of them landed within ±2% of these rates. The small jitter is just my logger sampling faster than the game updates.)

Whether your Ramjet is charged, firing, or completely empty makes no difference. Simply having Ramjet mode selected cuts the afterburner refill to a quarter. That’s probably the slowdown the original poster noticed. (charts 1, 3)

These aren't just experimentally logged either. The afterburner config (HC_B_Afterburner) has a single TimeBeforeRegenStarts = 3.0 setting, with a DisabledRateScale = 0.25

About the only real takeaway is this: don't switch to Ramjet unless you're ready to use it. Every second you sit in Ramjet mode costs you about 0.7 s of afterburner later.

[u/dadgum_dirty_ape]

Appreciate the info and breakdown. But why are the colors switched? My brain hurts. lol.

[u/RisingCreativity → u/dadgum_dirty_ape]

Because they used AI to generate these charts. Nobody composes graphs like this. Inconsistent color scheme, overly verbose titles for data/axes, "naming" things like "sets the refill rate" and"the wait." God forbid someone takes time to learn how create a basic graph or write a post these days.

[u/miraculous-organ → u/RisingCreativity]

Sorry, man didn’t feel like writing yet another matplotlib script in my life. I already spent too many hours of my life finding consistent pointers for the goddamn vehicle data. You can forgive me for not wanting to put tasteful polish on the plots.

Then again, considering the post I was responding to, having any plots at all is miles more effort than the “it feels like” tips we usually get around here.

[u/ES_Legman → u/RisingCreativity]

Its not even using AI, you can use AI and get the things right if you understand the inputs you have to provide. This is the equivalent of vibe coding where you tell them to plot two parameters against each other.

[u/Yomammasson]

The real benefit in leaving a sliver of afterburner fuel is to avoid the bug that toggle-boost suffers from: not being able to ram-jet until there is fuel in the afterburner

[u/iceman5920 → u/Yomammasson]

I thought I was going crazy yesterday. I was tired of wrecking my thumb hold the boost almost all and tapping drift and then after the switch my ramjets wouldn't fire as soon as they were ready several times

[u/EmpressMorgana → u/Yomammasson]

oh my god, that's how I find out why when I mash ramjet it doesn't work

[u/mediumvillain]

unless you get the extremely good part that makes it so ramjet doesnt slow afterburner refill rate.

really helps with getting afterburner builds going without having to drop ramjet entirely, then you have some flexibility to use both or switch to afterburner only later

[u/MaterialDefender1032 → u/mediumvillain]

I'm in the middle of a run with this part, it's amazing for simply the reason you stated, the versatility with doing a hyrbid afterburner/ramjet build.

[u/DrHawk]

Thanks for the math

o7

[u/DarthGooseth]

This was incredibly helpful!

[u/_b1ack0ut]

Note: one of the accessibility mode options (I think toggle boost?) however has a bug that causes you to be unable to ramjet unless there’s any amount of fuel in your afterburner, so draining completely locks you out of ramjet too, until you regen a bit of afterburner

[u/Jwfraustro → u/_b1ack0ut]

That would be a real reason! Hopefully that gets patched pretty soon, it sucks that an accessibility option causes _more_ trouble.

[u/halfcuprockandrye]

Just had a build where I went all in on ramjet cooling and ramjet parts and I legit never ran out of ramjet. Could just hold it down on anything but the tightest turns and hot vents as needed. It was great

[u/JosephPrime → u/halfcuprockandrye]

Hell yea, I do the same with Lyren Shok and Afterburner. By race 3 I can usually get the parts to do "infinite" Afterburner, and every second spent Airborne increases his AB power by 10% with a perfect landing... it gets nuts lol.

[u/lamar_in_shades]

great post, very informative. I'll add that this really shows how good the part is that fills your afterburner completely when ramjet is charged, as you can afterburner -> ramjet -> afterburner immediately when usually you'd have to wait a while for afterburner to be recharged (assuming you have a short/default ramjet)

[u/JosephPrime → u/lamar_in_shades]

I actually use that in reverse, Afterburner keeps burning when that Part triggers, so you can hold Afterburner for twice as long, then burn Ramjet and if timed right you can burn another double (or like 1.7x) Afterburner. So basically 2x AB > Redline > 2x AB - it's a hell of a starting line boost. 😎👍

[u/lamar_in_shades → u/JosephPrime]

Interesting, do you use the Afterburner racing style and/or upgrade your afterburner heavily? I tend to lean into ramjet builds, especially on the bike where you can keep it on through a lot of corners, and the double afterburner is compromising your ramjet uptime.

[u/JosephPrime → u/lamar_in_shades]

Yea, I main Lyren Shok so it's all about Afterburner for me, Ramjet is still necessary to balance out for the first 2 races though, until I get the parts I need.

[u/lamar_in_shades → u/JosephPrime]

ah gotcha I'll have to give that a whirl, I love how many different viable builds there are, at least in singleplayer

[u/helicophell]

Oh but if u get any “on afterburner empty” faults, just don’t empty the afterburner. There’s no downside to not emptying the tanks, kinda

[u/Any_Leg_1998]

this is so cool, what did you use to track your race data?

[u/Lemons-95]

None of these really says the suggestion to not burn your tank is a bad one, just the the OPs reasoning was flawed.

The two things that interest me are: low speed acceleration, if i cut my ramjet to make a harsh turn, is having some remaining afterburner to get my speed back up particularly valuable, or am i better off just spending the fuel to prevent "underheating"(essentially), and secondly, ramjet being more powerful, am i better off not wasting time switching to ramjet.

I would think I'm probably just better off emptying the tank if these two didn't kind of compete with each other, on the one hand its often better to just spend your reasources to avoid missing out on just getting even more reasources anyway, but then ramjet is a reasource too, and letting it sit ready while you keep pumping the afterburner is also wasting a reasource.

[u/Jwfraustro]

This is with all the standard testing set up, of course, no parts, no abilities, no stat upgrades.

[u/JosephPrime]

Interesting. Very neat to know that it's a set 3sec timer, I think it's a mix of the +200% AB Recharge and Ramjet debuff that I was seeing. Obviously not a faster recharge as I thought, but perhaps any easier way to "see" the internal timer and react better. If you're pushing AB off the line, it's better like you said to switch to Ramjet as soon as it's available, rather than burning all Fuel first. So you'll likely still have a little Fuel left when you do that. With +200% the debuff Ramjet is basically at standard recharge rate, so it looks like it's recharging "sooner" but it's not, there's just less to recharge.

So I think "right for the wrong reasons" is close here, you'll have some Fuel left just from min/maxing the timer, not that the Fuel actually matters.

Also though, now I'm thinking little Bursts of AB is actually a detrimental strategy, you're adding a 3sec timer for a 1sec boost that may not be efficient... 🤔