Injecting E85 fuel in charge pipe?

[Daniel Jost]

Hello,

So I have been debating on running secondary injection in my car. I want to accomplish it using two 120-160# fuel injectors in the charge pipe pre-throttle body. My reasoning behind this is I have 80# injectors as the primary injectors and I am worried if I went any bigger the car would have too much fuel to effectively idle on 91 octane.

The electronics of it is not a problem as the megasquirt has control for them. I want to get the injector weld mounts for the charge tube from DIYAUTOTUNE.com which would make mounting them easy. Where I run into a problem is the actual fuel flow through the intake with a power plate, will our intakes flow fuel correctly? I know they seem to do fine with methanol but that's a little different application than primary fueling.

Thanks, Dan

 

[Jerryl]

IMHO . . . It could be a problem. Have not run the calcs and its been a while since i looked at this stuff . . . but it may be too much fuel (?) in an intake that is not designed for wet flow.

For the record. I stayed at a Holiday Inn express last week so this is an opinion.

 

[NY Twin Turbo]

Why not just put alky injection?

 

[ITSAV6]

I see you have megasquirt, so you wanna run 6 inj when on gasoline and 8 inj when on e85? Or are you gonna have a secondary fuel system and run e85 with the secondary injectors?

 

[BEATAV8]

Back in the day there were a few "7th injector" kits available from places like ATR. These kits added an additional injector in the up-pipe and turned it on when the engine came up on boost. So it's been done before and its known to work.

 

[Jerryl]

Back in the day there were a few "7th injector" kits available from places like ATR. These kits added an additional injector in the up-pipe and turned it on when the engine came up on boost. So it's been done before and its known to work.

Agree. There are no issues with the principal.
Do you recall what size injector was used on the the ATR kit?

I know turbofabricator build a 2 injector up-pipe kit way back.

 

[BEATAV8]

No not sure what they used. May have been a stock injector? Not sure.

 

[Daniel Jost]

Hey guys sorry for not replying sooner.

Jerryl- Your cracking me up with the holiday express comment.

NY Twin Turbo- I already have alcohol injection, it does not have the benefits that I like about E85.

ITSAV6- Yes I am looking to phase on the 2 additional injectors in the charge pipe and they will run off of their own VE table in the Megasquirt that is for this exact type of application. I will only have them active when on E85 and they will be fed off the main -8AN fuel line.

I am looking to use the stand alone fuel injector bosses from DIYautotune and TIG them to my charge pipe right before the throttle body and fit them with 160# injectors. I will just feed them with a 3 or 4an line each. This would give me an extra 50+# per cylinder of fuel, which makes me wonder if it will work as intended since its a substantial amount of liquid flow more than the 7th injector or alky that has been done before. I might have to just do it and see how it works.

Thanks, Dan

 

[ITSAV6]

It should get plenty of fuel, this is to further cool the intake charge?

 

[Daniel Jost]

It should get plenty of fuel, this is to further cool the intake charge?

More fuel is the main reason since I only have 80# injectors in the car now and they were maxed out at only 23# last year. Cooling the intake charge will be a nice side effect of injecting up stream but as we know most of the cooling happens in the chamber.

Thanks, Dan

 

[ITSAV6]

Maxed out running E85?

 

[20psiofevil]

Interesting concept. Seems over complicated to me but that's my opinion. 120lb injectors will not idle correctly? Distribution would be my concern, and fuel puddling. Sub'd for updates though.

 

[NY Twin Turbo]

I'm using 160 lb injectors with 93 pump gas. My idle is pretty good. I'm wondering why 120 would idle so bad? Especially since when using E-85, the pulse width would have to be something like 37% wider for the same burn.

If the idle does suffer just a little, I would most likely tolerate it just to maintain simplicity. Also It would save me the minor burden of doing fabrication work and adding in the additional hosing.

Just something to think about.

 

[Daniel Jost]

I'm using 160 lb injectors with 93 pump gas. My idle is pretty good. I'm wondering why 120 would idle so bad? Especially since when using E-85, the pulse width would have to be something like 37% wider for the same burn.

If the idle does suffer just a little, I would most likely tolerate it just to maintain simplicity. Also It would save me the minor burden of doing fabrication work and adding in the additional hosing.

Just something to think about.

Your car must flow some serious air! Is your engine a stroker? What heads/intake and cam are you running? Do you have your idle MS/RPM/AFR by chance to give me a idea of how mine would realistically compare?

I looked at one of my logs and on 91 gasoline I am seeing a 2.1ms injection pulse at a 12AFR and 800 RPM. So with 160# injectors that would be theoretically cut back to about 1.05MS which would very close to the rock bottom on those injectors.

Thanks, Dan

 

[regalized]

I'm running 120 s, with e85, stock ecm and a versafueler, works great. 6.88@ 100mph

 

[NY Twin Turbo]

Your car must flow some serious air! Is your engine a stroker? What heads/intake and cam are you running? Do you have your idle MS/RPM/AFR by chance to give me a idea of how mine would realistically compare?

I looked at one of my logs and on 91 gasoline I am seeing a 2.1ms injection pulse at a 12AFR and 800 RPM. So with 160# injectors that would be theoretically cut back to about 1.05MS which would very close to the rock bottom on those injectors.

Thanks, Dan

My combo is significantly different from yours.

However, that shouldn't matter much. I don't think 160's are the right ones for you. But I do believe 120's could be made to work. Remember your pulse width will be increased with E-85. I also idle my car at 1000. If yours needs a little RPM, then through another 100 at it.

I only run 93 on the street. My idle AF is at 12.7. It seems to like it there so I don't argue with it. If I go leaner it will start to roll.

Keep it simple if you can. You may be doing this stuff all over again the next time you upgrade and go even faster.

 

[Daniel Jost]

My combo is significantly different from yours.

However, that shouldn't matter much. I don't think 160's are the right ones for you. But I do believe 120's could be made to work. Remember your pulse width will be increased with E-85. I also idle my car at 1000. If yours needs a little RPM, then through another 100 at it.

I only run 93 on the street. My idle AF is at 12.7. It seems to like it there so I don't argue with it. If I go leaner it will start to roll.

Keep it simple if you can. You may be doing this stuff all over again the next time you upgrade and go even faster.

I have two options here either go with the 120's and a versafueler which know will work or try with 160s, but like NY stated above I'd like to go as big as possible now while I'm upgrading. On E85 I have no concerns of fueling at idle since I see approximately a 25% increase in pulse.

Thanks, Dan

 

[dandaman]

Were using id2000 with ethanol and 60psi base pressure and car idles ok at 1000rpm. Big cam too. @60psi they have been flow tested to be around 250 lb.

 

[Daniel Jost]

Well for an update here I picked up a Versafueler (MS can only run 4 Low-Z natively) for real cheap from a guy that went to High-Z injectors. I think I have decided on 120# injectors as I know they will work with my engine combo and gasoline for when I'm on road trips where E85 is not as available as the corn belt. Once I started figuring the cost of 2 high-z injectors and the bungs plus the extra wiring and plumbing it's not nearly worth the hassle when I know I can make 120's work and will be more than enough for quite some time.

Thanks, Dan

 

[regalized]

Great choice, very happy with my Versafueler and 120s.