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I have some downtime due to winter, and just wrapped up converting the car over to flex fuel. We don't get E85 at the pump over here in Canada, but I will be running Ignite E90 Race gas. I'll be mixing it with 99-100 RON pump gas and shoot for 50% ethanol content, up to possibly 85% content if there's any noticeable gains.

Here's the question. Most I'll ever want to hit is ~600rwkW. I've currently running 1200cc injectors and want to keep them under 90% duty cycle. As per some online injector calculators, I should be good with 1200's well past 600rwkw on E85. As per other calculators, I'll need 1600-2000cc's. The variety is rather amusing. 

With you Australians having E85 at the pump, what realistic duty cycles are you seeing in those kW ranges on E50 & E85 on your injectors?

Thanks, 

Edited by TurboTapin

A bit of data is always good, beats the Facebook experts with their opinions :)

Although the kWs aren't anywhere near what you are after, it should give you a good indication.

I have Bosch 1480cc injectors, often called 1650cc (only when run at 4bar). I run mine at 3bar base so I don't thrash the fuel system.

Up top, making 437kW with boost dropping, injector duty is at 69% on E80 (might have had some residual 98RON in there)

image.thumb.png.d5798fa7efb3a956c01b7067d40e75f0.png

 

I would say that 1200s are only good for about 500rwkW (at close to 100% DC). That's with a standard (for Australia, braked roller dyno) discount of 25% from engine power.

Dose's 1480 should be good for a bit less than 650 rwkW, which aligns very very nicely with his ~70% duty at 437rwkW. I get within about +/-5rwkW of 635 approaching the calc from either end.

  • Like 2

Full e85 barrell stuff real world for reference if it helps as Ive pushed 2 x sets injectors to limit

Above mentioned Bosch 1480cc run on 4 bar base to the apparent 1650cc on rb2.7 yielded 912hp / 684  kw  at 92% duty on hub dyno

ID1700's - RB 2.8 ...1015hp / 760 kw at 87% duty - hubber dyno + shown off data on track

my opinion IF you change injectors just go bigger than you think you need the modern/ good larger ones run just fine if tuned properly even if way bigger than required even on streeters

 

Edited by bcozican
  • Like 1
  • 3 weeks later...

I'm late to the party. Been busy with a newborn... Keeping me up at all hours of the night. 

I'll look into purchasing ID 1750's then! Thanks everyone for the concrete evidence. 

  • Like 1
4 hours ago, TurboTapin said:

I'm late to the party. Been busy with a newborn... Keeping me up at all hours of the night. 

I'll look into purchasing ID 1750's then! Thanks everyone for the concrete evidence. 

When you looking to buy injectors?? I could possibly sell you my 1d1700s for decent price. Done little work I just need bigger again 😫 

Edited by bcozican
  • Like 1
5 hours ago, bcozican said:

When you looking to buy injectors?? I could possibly sell you my 1d1700s for decent price. Done little work I just need bigger again 😫 

Let me know how much you're looking to get! Thanks. 

  • Like 1

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