Let's work out a few patterns while boosting with Fire Stingray.
When I say "Bonus distance traveled", the units are in 1/256 of a pixel. This is how much additional distance I cover above and beyond what the usual maximum speed would allow during a single cycle of the boost pattern.
I provide both hexadecimal and decimal values. I prefer hexadecimal, since I can very neatly line up speed values in my script, and I have no clue how to do so in decimal.
No brakes
65 frame cycle
Bonus distance traveled: 0x2080 - 8320
Average speed: 0x0980.00 - 2432.00
A00-9FC-9F8-9F4-9F0-9EC-9E8-9E4-9E0-9DC-9D8-9D4-9D0-9CC-9C8-9C4-
9C0-9BC-9B8-9B4-9B0-9AC-9A8-9A4-9A0-99C-998-994-990-98C-988-984-
980-97C-978-974-970-96C-968-964-960-95C-958-954-950-94C-948-944-
940-93C-938-934-930-92C-928-924-920-91C-918-914-910-90C-908-904-
900 - Repeat
2560-2556-2552-2548-2544-2540-2536-2532-2528-2524-2520-2516-2512-2508-2504-2500-
2496-2492-2488-2484-2480-2476-2472-2468-2464-2460-2456-2452-2448-2444-2440-2436-
2432-2428-2424-2420-2416-2412-2408-2404-2400-2396-2392-2388-2384-2380-2376-2372-
2368-2364-2360-2356-2352-2348-2344-2340-2336-2332-2328-2324-2320-2316-2312-2308-
2304 - Repeat
This one's purpose is only really any good when at the tail end of your boost, when there isn't time to accelerate again under boost power. Also, there's enough time to go through four of these, then your boost cuts off shortly before you get your fifth.
8 frame brakes - Begin braking from 0x0970 - 2416
45 frame cycle
Bonus distance traveled: 0x1C20 - 7200
Average speed: 0x09A0.00 - 2464.00
A00-9FC-9F8-9F4-9F0-9EC-9E8-9E4-9E0-9DC-9D8-9D4-9D0-9CC-9C8-9C4- Coast
9C0-9BC-9B8-9B4-9B0-9AC-9A8-9A4-9A0-99C-998-994-990-98C-988-984- Coast
980-97C-978-974- Coast
970-962-954-946-938-92A-91C-90E- Brake
900- Accelerate (Repeat)
2560-2556-2552-2548-2544-2540-2536-2532-2528-2524-2520-2516-2512-2508-2504-2500- Coast
2496-2492-2488-2484-2480-2476-2472-2468-2464-2460-2456-2452-2448-2444-2440-2436- Coast
2432-2428-2424-2420- Coast
2416-2402-2388-2374-2360-2346-2332-2318- Brake
2304- Accelerate (Repeat)
A lot better than simply coasting your way down, as you get rid of most of the slow half of the boost cycle in favor of a faster cycle with more of the high speed intact. Brakes reduce speed at 0xE or 14 per frame when you're traveling somewhere between 0x900 (2304) and 0x97F (2431), and reduce it at 0x0F or 15 at higher speeds (
for most practical sorts of speed to brake at, anyway). If I were to brake for two more frames, they'd be reducing speed at the 0xF or 15 rate for one frame, leaving my speed at 0x8FF or 2303 before I can accelerate to 0x9FF or 2559, which leaves me traveling slower for the next cycle.
11 frame brakes - Brake at 0x099C - 2460
37 frame cycle
Bonus distance traveled: 0x17EF - 6127
Average speed: 0x09A5.98 - 2469.59
A00-9FC-9F8-9F4-9F0-9EC-9E8-9E4-9E0-9DC-9D8-9D4-9D0-9CC-9C8-9C4- Coast
9C0-9BC-9B8-9B4-9B0-9AC-9A8-9A4-9A0- Coast
99C-98D-97E-970-962-954-946-938-92A-91C-90E- Brake
900- Accelerate (Repeat)
2560-2556-2552-2548-2544-2540-2536-2532-2528-2524-2520-2516-2512-2508-2504-2500- Coast
2496-2492-2488-2484-2480-2476-2472-2468-2464- Coast
2460-2445-2430-2416-2402-2388-2374-2360-2346-2332-2318- Brake
2304- Accelerate (Repeat)
The best way to remove the slow half of your speed without handy rails. In order to make up for the fact you can only decelerate at 0xE for one more frame, we decelerate 0xF for two frames in order to line up our speed to accelerate optimally.
12 frame brakes - Brake at 0x09B0 (2480), with one frame coast gap
34 frame cycle
Bonus distance traveled: - 0x15DA - 5594
Average speed: 0x09A4.87 - 2468.53
A00-9FC-9F8-9F4-9F0-9EC-9E8-9E4-9E0-9DC-9D8-9D4-9D0-9CC-9C8-9C4- Coast
9C0-9BC-9B8-9B4- Coast
9B0-9A1-992-983- Brake
974- Coast
970-962-954-946-938-92A-91C-90E- Brake
900- Accelerate (Repeat)
2560-2556-2552-2548-2544-2540-2536-2532-2528-2524-2520-2516-2512-2508-2504-2500- Coast
2496-2492-2488-2484- Coast
2480-2465-2450-2435- Brake
2420- Coast
2416-2402-2388-2374-2360-2346-2332-2318- Brake
2304- Accelerate (Repeat)
Minimally slower than the 11-frame brake's average, but intentionally inserts one coasting frame in the middle of braking in order to avoid nasty stuff with speed no longer lining up cleanly at 0x0900 (2304) exact. However, this does allow a way to tweak with the exact timing in case the course goes through certain twists and turns where the difference in timing is critical.
R2RB4 - Rail 2 frames, Rail Brake 4 frames
27 frame cycle
Bonus distance traveled: 0x13D0 - 5072
Average speed: 0x09BB.DA - 2491.85
A00-9FC-9F8-9F4-9F0-9EC-9E8-9E4-9E0-9DC-9D8-9D4-9D0-9CC-9C8-9C4- Coast
9C0-9BC-9B8-9B4- Coast
9B0-99C- Coast on rail
988-96A-94C-92E- Brake on rail
910- Accelerate on rail (Repeat)
2560-2556-2552-2548-2544-2540-2536-2532-2528-2524-2520-2516-2512-2508-2504-2500- Coast
2496-2492-2488-2484- Coast
2480-2460- Coast on rail
2440-2410-2380-2350- Brake on rail
2320- Accelerate on rail (Repeat)
This is a very fast pattern. It works because the rail slows you down by 0x10 (16) before applying your acceleration or brakes. So braking at 0x988 slows me down by 0xE rather than 0xF, which helps to align my speed nicely. Then I can accelerate at 0x910 rather than going all the way to 0x900. I love these rails!
R3RB4 - Rail 3 frames, Rail Brake 4 frames
23 frame cycle
Bonus distance traveled: 0x10E8 - 4328
Average speed: 0x09BC.2D - 2492.17
A00-9FC-9F8-9F4-9F0-9EC-9E8-9E4-9E0-9DC-9D8-9D4-9D0-9CC-9C8- Coast
9C4-9B0-99C- Coast on rail
988-96A-94C-92E- Brake on rail
910- Accelerate on rail (Repeat)
2560-2556-2552-2548-2544-2540-2536-2532-2528-2524-2520-2516-2512-2508-2504- Coast
2500-2480-2460- Coast on rail
2440-2410-2380-2350- Brake on rail
2320- Accelerate on rail (Repeat)
The fastest pattern, though the R2RB4 is only barely slower. There's room for 11 of these on a single boost, with only two spare frames after 11 cycles. You can bet this cycle is used very often whenever I'm boosting on straightaways. Specifically any of those that go straight vertical or horizontal, as the diagonal ones have a jagged edge for the rail, interfering with this pattern.
During a boost, the accelerator is useless for maintaining speed, so you only need to press it for one frame in order to accelerate. If you're not turning, and the accelerator is off, your momentum stays constant, whatever direction you happen to face. This little detail gives a lot of control when it comes to dealing with the rail in order to move into it and back off of it at exactly the right times. Without that, this cycle would be very difficult to pull off consistently even in TAS conditions.
Now, here's the fastest sets put together:
6x R2RB4
4x R3RB4
1x No Brakes
Total bonus distance: 56064
Base speed: 2304
Frames needed for base speed to cover this distance: 24.33
Number of seconds by in-game clock: 0.365 seconds
More time than that should be saved due to taking corners more sharply, where going over the dirt or rail would otherwise ruin your speed and impact your time worse than what you'd have saved.