E30 vs 100 octane JB4

felcrum

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I have a downpipe, with a JB4 with the EWG. I've been running E30 with no problems. Is it ok to use 100+ octane on map 5?

My understanding is that octane is the name of the game.
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Reach out to BMS with a log.
they will tell you if youcan go up or not.
if you don’t have a bef, stay in map 3/4
 

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Isn't map 5 what's been killing the Supras posted on FB?
 

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Jb4 is like the pull out method. You use a map and pray your car is fine and doesn’t blow up! Lol ?
Maybe JB4 OTS maps are, but the tool itself is fine. It's just a tool.
 

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I have a downpipe, with a JB4 with the EWG. I've been running E30 with no problems. Is it ok to use 100+ octane on map 5?

My understanding is that octane is the name of the game.
you can use map 5 with 100+ octane

Keep in mind E30 is 95-96 octane depending on the mix.
In theory you should be able to run an even more aggressive map with 100+
 

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you can use map 5 with 100+ octane

Keep in mind E30 is 95-96 octane depending on the mix.
In theory you should be able to run an even more aggressive map with 100+
Definitely. Octane rating of pump e85 can vary (and often misreported by websites), but it's mostly in the range of 100-105. If you target 50% ethanol mix: pump 93 @ e10% + e85 @ e85% can get you to ~100 octane. If the "e85" pump has a lower ethanol content than 85%, it's possible to get the octane even higher as you have to increase the e85 gallons pumped to reach e50. Definitely room to be more aggressive.
 

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Definitely. Octane rating of pump e85 can vary (and often misreported by websites), but it's mostly in the range of 100-105. If you target 50% ethanol mix: pump 93 @ e10% + e85 @ e85% can get you to ~100 octane. If the "e85" pump has a lower ethanol content than 85%, it's possible to get the octane even higher as you have to increase the e85 gallons pumped to reach e50. Definitely room to be more aggressive.
I'm lucky to have my pump provide 53% so no mixing is needed. Though when I add port injection, I wish I had a higher mix available.
 
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Definitely. Octane rating of pump e85 can vary (and often misreported by websites), but it's mostly in the range of 100-105. If you target 50% ethanol mix: pump 93 @ e10% + e85 @ e85% can get you to ~100 octane. If the "e85" pump has a lower ethanol content than 85%, it's possible to get the octane even higher as you have to increase the e85 gallons pumped to reach e50. Definitely room to be more aggressive.
If I have access to 103 or 106 octane with e10-e15, then no ethanol is need at all right? As I understand it, the goal of the ethanol is to provide a higher octane rating (meaning it's less susceptible to pre-ignition) among other thing.

Or is there any benefit the ethanol provides besides an octane boost?
 

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eMix's benefits aren't just about octane, though that's the primary benefit: cheap-and-easy(ish) octane that's better than 93, and it comes from a pump. You're right, that part helps with early detonation and knock resistance.

But the ethanol content also substantially cools the temperature of the intake charge, in the same kind way your hand feels ice cold when you let isopropyl alcohol evaporate on it. Same physical effect at work. Its temperature of combustion is also lower than petrol, which further provides cooling benefits. Because of the lower combustion temps, the EGTs are lower (great for turbo hotside temps).

And best of all, ethanol is 30% oxygen molecules by weight. So when you're stuffing the cylinders with air, you can actually dial back the boost a bit to make equal or more power, because the oxygen content of the E can make up the gap.

These thermal and oxygenation benefits have diminishing returns after about e50, which is why everyone seems to see peak benefit around that threshold without peaking out the injector duty cycle.
 

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Isn't map 5 what's been killing the Supras posted on FB?
Haven't heard anything about this but in my personal experience map 3 pulls better than map 5... that being said I really only posted like one log on the forums and have been doing 3gal e85 every fill up since
 

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I guess I should probably take the time to dial in a map but for now it scoots pretty good, no complaints
 
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felcrum

felcrum

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I guess I should probably take the time to dial in a map but for now it scoots pretty good, no complaints
I'm with scooter. Map 4/5 with e30 as close as possible.
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