850cc injectors with e85 ???

[superorange]

I am wondering how much boost i could run on e85 with 850cc injectors, with a fp18g tubo. I have a 255 fuel pump, fpr, dsm link, and basic exhaust, and a front mount setup. I have a eagle/weisco combo with arp studs. just wondering how much boost i can run on e85 with 850cc injectors? Would i be holding myself back a lot by not getting bigger injectors? i got the 850's for free so i was just going to use them. I also have 550cc injectors that are in the car now that are coming out with the 16g this week.

 

[93_tsi_fwd]

Probably around 15-20 psi from what i was told by my tuner. Was gonna runs e85 on my 880s but was gonna be running high idc %. Just sell those 850s and get some bigger ones.

 

[spooling hard]

What is "basic exhaust"? Stock, 2" 3" etc...

I have 1050cc injectors and a holset hx40 and I can run 30psi at 74% idc. You should be fine with your set up at any amount of boost on that turbo with a good tune. Check your idc when you do some logs and post a log.

 

[Doubleot]

880cc injecctors won't be able to handle more then 15 psi on E85. I know this from a few locals who have tried it and the IDC was in the higher 90's. Generally you don't want to be above 85% IDC.

Even with a good tune I wouldn't recommend running E85 with anything smaller then 1000cc injectors. Just my .02

 

[superorange]

i can sell the two sets of injectors for the cost of bigger ones, im not worried about the cost you know. so it sounds like i would be wasting my time with those injectors, what injectors do you guys think for e85 and the fp 18g.


as for the "basic exhaust" it is not pretty but it is 3 inch is what i mean by that no leaks at least.

 

[BigBeans]

Blind leading the blind ITT. Stop talking about PSI like it means something. Pressure doesn't matter, you guys should be discussing flow.


You'll hit 90%DC at about 42lbs/min with 850s on E85. You need a global correction factor of -31% with DSMlink.

 

[snowborder714]

850cc injectors on pump will be the same as 570cc injectors on E85. Look in this link and match up the 570cc with the closest other injector size to see what those injectors will support.
http://www.dsmtuners.com/forums/articles-tuning-ecu/366003-injector-fuel-pump-supported-airflow.html

 

[superorange]

thank you snowboarder. I am looking to get 1200cc to 1600cc injectors and just selling my two sets i have now. with my setup of a 255 fp, fpr, dsmlink 2.5 and maf translator, i should be able to get a pretty decent tune with anything over 1200cc injectors i would think. I just want a pretty reliable street car, and would like to trap around 115mph in the 1/4. hopefully with the fp 18g and my supporting mods/ weight reductions it will be possible.

 

[superorange]

i found some 1050cc injectors would i still be in the same boat? my buddy has a 2g with 1600cc injectors now and he says it doesn't idle the best cause of the injectors, I'm not sure but i think its more the brand than the size he has

 

[snowborder714]

1050cc on pump = 704cc on E85. Just take the injector size and multiply it by .67 to find out what it'd be for E85.

It's definitely more the size than the brand. Certain large injectors (typically 1450 to 1600) just don't like to idle or cruise well.

 

[Josh2g]

i found some 1050cc injectors would i still be in the same boat? my buddy has a 2g with 1600cc injectors now and he says it doesn't idle the best cause of the injectors, I'm not sure but i think its more the brand than the size he has

Too big of an injector size and your idle will be garbage. You need to be in the 1000cc-1200cc range. Try this calculator out, Injector Size Selection Calculator

 

[bastarddsm]

1050cc on pump = 704cc on E85. Just take the injector size and multiply it by .67 to find out what it'd be for E85.

It's definitely more the size than the brand. Certain large injectors (typically 1450 to 1600) just don't like to idle or cruise well.

Eh.... You run E85? its more like .75 With E85 you run waaay leaner ratios than on pump gas. E85 your actually running like 8.5:1, and on pump gas you generally have to be about 10.5-11:1 to stay out of knock with much boost. That works out to be about .77- .71, and I have found that setting my global to .75 of what my injectors actually are works best.


Anyway, if your not going to run over 30psi, and have a 255HP, stick a 1gn/t regulator on there. It bumps the base fuel pressure up to about 50. (supposed to be 47). That's how I get away with 750's on E85 making 460whp. I do run them to 100% dc tho.


You will be fine with 850's and an 18g.

 

[donniekak]

Eh.... You run E85? its more like .75 With E85 you run waaay leaner ratios than on pump gas. E85 your actually running like 8.5:1, and on pump gas you generally have to be about 10.5-11:1 to stay out of knock with much boost. That works out to be about .77- .71, and I have found that setting my global to .75 of what my injectors actually are works best.


Anyway, if your not going to run over 30psi, and have a 255HP, stick a 1gn/t regulator on there. It bumps the base fuel pressure up to about 50. (supposed to be 47). That's how I get away with 750's on E85 making 460whp. I do run them to 100% dc tho.


You will be fine with 850's and an 18g.

I run a 20g at 32psi with 850's and a n/t regulator. Holds a rock solid 12.3 afr to 7500 rpm's. My injector size is set to somewhere in the upper 700's in my eprom image, as the jump in pressure raises the 850's to over 1000cc's.

 

[snowborder714]

Eh.... You run E85? its more like .75

Yes, I do. Not sure where the .75 came from, but here's two sources that I use that show very close to .67.
e85fuel [ECMTuning - wiki]
E85 Global Calculation Info

 

[donniekak]

Yes, I do. Not sure where the .75 came from, but here's two sources that I use that show very close to .67.
e85fuel [ECMTuning - wiki]
E85 Global Calculation Info

Maybe it's the mix i get, but i first started trying to tune cars off of the 67% factor, and it was always to rich. Even with 1000cc injectors that flow a good bit less than advertised, i always come out to around 700cc's for my injector sizing(edited eprom).

 

[bastarddsm]

Yep, they infact do say its .67 The number .75 comes from running E85 longer than you have been on this board. At the end of the day, who cares what the number is. The end of the story is "You don't need as big of injectors as everyone tells you."

Maybe it's the mix i get, but i first started trying to tune cars off of the 67% factor, and it was always to rich. Even with 1000cc injectors that flow a good bit less than advertised, i always come out to around 700cc's for my injector sizing(edited eprom).

Doubtfull. Down there you probably have class 1 fuel all the time. I check mine regularly, and I usually have E82.

But, I have had some mixes as low as E60 from putting 93 in just to get to an E85 station. It barely affected the fueling, but I had to pull 5* of timing out to keep it from knocking.

 

[superorange]

it looks like i am going to go for delphi 1000cc injectors and see how much boost i can get out of them, i would be very happy with 30 psi or more on those injectors, and very dissapointed with lest than 27. hope i can do that and reach my goal of 115 mph trap in th 1/4.

 

[Doubleot]

You have some high hope buddy. Good luck getting anything over 22psi on those with E85.


Post pictures of your blown motor.

 

[donniekak]

You have some high hope buddy. Good luck getting anything over 22psi on those with E85.


Post pictures of your blown motor.

My engine runs fine on e85, 47 psi base pressure, 850's and 32 psi of boost..

 

[D's GS-T]

There is a guy around here with 850s or 880s and he runs like 29 psi on E85. It can be done.

 

[TSIMonsteR]

My engine runs fine on e85, 47 psi base pressure, 850's and 32 psi of boost..

On an internally gated 20g?

 

[Doubleot]

My engine runs fine on e85, 47 psi base pressure, 850's and 32 psi of boost..

That just sounds insane. Care to post up a log?

 

[phunny]

Eh.... You run E85? its more like .75 With E85 you run waaay leaner ratios than on pump gas. E85 your actually running like 8.5:1, and on pump gas you generally have to be about 10.5-11:1 to stay out of knock with much boost. That works out to be about .77- .71, and I have found that setting my global to .75 of what my injectors actually are works best.


Anyway, if your not going to run over 30psi, and have a 255HP, stick a 1gn/t regulator on there. It bumps the base fuel pressure up to about 50. (supposed to be 47). That's how I get away with 750's on E85 making 460whp. I do run them to 100% dc tho.

I personally run a FPred at at 55lbs/minute I'm at 62%IDC and thats with FIC 2150's.
You will be fine with 850's and an 18g.

Do you even read what you post?...

Yep, they infact do say its .67 The number .75 comes from running E85 longer than you have been on this board. At the end of the day, who cares what the number is. The end of the story is "You don't need as big of injectors as everyone tells you."


Doubtfull. Down there you probably have class 1 fuel all the time. I check mine regularly, and I usually have E82.

But, I have had some mixes as low as E60 from putting 93 in just to get to an E85 station. It barely affected the fueling, but I had to pull 5* of timing out to keep it from knocking.

Yeah so you think since you've been running E85 for a long time you're the site guru? And I love this quote "who cares what the number is"? Are you kidding? Just stop giving this "advice."

OP it's just a few simple match calculations to figure this out and I think someone posted some links to it. Better to research this yourself so you don't damage your car by listening to some of the people on here.

 

[rhtwng2]

you really don't want to run e85 on less than 1450cc injectors. Now I'd sell those puny 850's and step up to the Injector Dynamics 1000cc. Nice thing about e85 is that you get around 98 to 102 octane however you use 25% more fuel. I get 18mpg on e85 with a 540HP engine on average. Good thing e85 is only 3.25 a gallon.

 

[sqr]

With 1050 Delphi's on E85, what is a typical duty cycle and pulse width at idle and say 60 mph cruise on a level road?