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Stock Twins and E85?

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Old Feb 16, 2020 | 06:09 PM
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Stock Twins and E85?

Anyone doing this? If so, are there any numbers? I have access to Ignite E85 locally, my car needs to be tuned anyway, and id like to start the process of going single (EFR probably) and was wondering if tuning for e85 on a haltech elite and stock twins is going to work?

I would like to run it this way for the season so i can work on a few other items (restoration wise) and then over the winter i want to complete the swap to single.

I did a search and did not find anything related to stock twins ON e85...

Thanks in advance!
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Old Feb 16, 2020 | 06:42 PM
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Most people don't run this because the stock and even upgraded twins themselves are the limiting factor on an e85 build. The sequential control is a pain in the butt, they don't hold together well near 20psi, and they max out south of 500hp. You can probably get high 300's out of the stock twins, without them coming apart. You can probably get high 400's on BNRs. By the time you get e85 in the mix, most people just go single.
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Old Feb 16, 2020 | 06:52 PM
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Well I do intend to go single later on, but currently the car needs a tune, so I’m going to start with a Haltech Elite 1500. I have intake and exhaust already. I can swing the cost of fuel upgrades and I figured if I switched to non sequential and ran 12psi it should be fine...

essentially I’ll move up in steps as finances allow... just need to get the tune dialed in and I figured I’d start running the ignite now if its not going to cause issues on the stock twins... it’s just their true e85 ... not the e90 or higher
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Old Feb 16, 2020 | 09:59 PM
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You have to get tuned again once you go single so why is it important that you do it now?
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Old Feb 16, 2020 | 10:15 PM
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Originally Posted by TwinCharged RX7
You have to get tuned again once you go single so why is it important that you do it now?
the car is currently running rich and it has boost creep due to the exhaust and intake mods. I want to tune it so I can continue to drive it and enjoy it until I’m ready to move up to the single and so on ...
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Old Feb 16, 2020 | 10:39 PM
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So get it tuned as it is and then tune again once single. I don't see how that creates any reason to go E85 now. You need to get it tuned twice either way.
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Old Feb 17, 2020 | 08:00 AM
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From: cold
E85 also doesn't start as well cold (especially without a lot of thorough tuning and hopefully flex fuel sensor capable system), and you live in Nebraska, so you probably have some cold mornings.
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Old Feb 17, 2020 | 11:23 AM
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From: https://www2.mazda.com/en/100th/
the E85 has better resistance to knocking, and it helps with temps, so it actually would probably work nicely with the stock twins. your boost limit is still the same, basically turbo shaft speed, but you can probably tune it more optimally

you do need about 40% more volume, so you need bigger injectors
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Old Feb 17, 2020 | 12:08 PM
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You can safely max our the twins on pump gas. Yes E85 is more knock resistant, but doesn't matter much if you can safely do it on pump.
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Old Feb 17, 2020 | 02:07 PM
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I guess I was just curious if anyone had any power numbers on stock twins with e85. I have access to the best e85 money can buy, and I will eventually run it with the single turbo setup when i get it, so i figured i would start running it now since i can tune for it... thanks for the input everyone!
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Old Feb 17, 2020 | 02:16 PM
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Originally Posted by AGuidroz
Well I do intend to go single later on, but currently the car needs a tune, so I’m going to start with a Haltech Elite 1500. I have intake and exhaust already. I can swing the cost of fuel upgrades and I figured if I switched to non sequential and ran 12psi it should be fine...

essentially I’ll move up in steps as finances allow... just need to get the tune dialed in and I figured I’d start running the ignite now if its not going to cause issues on the stock twins... it’s just their true e85 ... not the e90 or higher
Can't believe nobody has mentioned it yet, but you can't run sequential twins on an Elite 1500. For sequential, you'll need the Elite 2500 but if you want to run the twins in parallel you could get by with the 1500.

Skeese
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Old Feb 17, 2020 | 02:43 PM
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From: NEBRASKA
Originally Posted by Skeese
Can't believe nobody has mentioned it yet, but you can't run sequential twins on an Elite 1500. For sequential, you'll need the Elite 2500 but if you want to run the twins in parallel you could get by with the 1500.

Skeese
I'm aware of that. I was already planning to switch to non-sequential for the time being.
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Old Feb 18, 2020 | 09:16 AM
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From: https://www2.mazda.com/en/100th/
Originally Posted by AGuidroz
I guess I was just curious if anyone had any power numbers on stock twins with e85.
it would be 10-20hp more than gasoline. it does depend on you setup and tune somewhat.
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Old Feb 20, 2020 | 08:06 AM
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I'd just wait to go E85 until you have the ECU and single turbo setup. Going E85 means changing to ethanol compatible fuel lines and injectors, which will mean upgraded fuel rails, fuel pressure regulator, fuel filter, and fuel pump at the minimum. If you're ultimately going to go single turbo, you'll want to size all of that stuff for your end power goals so you don't spend money on going E85 for the twins then move to a single and have to do it all over again to up-size everything to suit the new higher power ceiling. I've managed to put myself in that situation a few times, and it just ends up taking more time and money when you could have planned it out from the beginning with headroom to grow.

I just don't think the money and effort to get everything running with the twins on E85 is justified for the minimal gains you'll see. I'd instead focus on sorting the single turbo setup first, and then building the E85 fuel system around the needs of the engine/turbo setup and then install it all at once and enjoy.

Skeese
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Old Feb 20, 2020 | 12:47 PM
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Keep in mine that all the soft seals in the motor, fuel system, premix, etc all have the be compatible with ethanol.
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