EFI Gods

[Northwest outlaw]

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[Team Addiction]

What exactly are you trying to do??

THere are a few calcs that can be done to establish inj size etc search BSFC (Brake specific fuel consumption.
A similar calc can be applied to an assumed BSAC (Brake specific air consumption) giving us a general idea how much said engine will flow. Therefore giving a good estimate of orifice size necessary to facilitate said airflow.

Besides all that fun. There are many kits that can give you a very nice starting point with plenty of room to fine tune the setup from there.

So whats it going on and what are your goals with said setup??

[Northwest outlaw]

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[Team Addiction]

cu,RPM/2
--------- Heres the formula for calculating airlfow.
1728 THis formula should be used to establish the engines airflow in CFM
From there find a TB that will flow as much CFM as the engine.

[Northwest outlaw]

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[Northwest outlaw]

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[rrussell]

532 + 7000 / 2 = 3766 does this look right so im looking at some that can flow 3766 cfm

Its 532CI x 7000rpm / 2 = 1,862,000

1,862,000 / 1728 = 1077.54 cfm

The 1728 is to convert cubic inches to cubic ft.

[rrussell]

yea it not a street car. I would like to stay with only 8 injectors but i dont know this is like talking IY*YLGIUHGLIYG to me.:)

8 ea. 160lb/hr injectors will support 1800 flywheel HP @ 85% duty cycle on petrol. The down side is you will need a efi system with a high rate of resolution and a sequential injection for good idle characteristics.

Plus the EFI system should have a high injector amperage available to help in keeping the injectors even when at idle with a low pulse width.

[Northwest outlaw]

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[rrussell]

yea i have been looking at this one what do you think.
MegaSquirt II Programmable EFI System PCB3.57 - Assembled w/ Black Case DIYAutoTune.com (http://www.diyautotune.com/catalog/megasquirtii-ems-system-smd-pcb357-black-case-p-171.html)

or is there one that i should look at?

It looks good to me. The main thing I can suggest is to get a system that will meet all your needs and one that is user friendly.

Also if you can, enroll in Ben Straders EFI 101 class its well worth the $$$$$ ;)

[Northwest outlaw]

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[Team Addiction]

Electromotive, Inc. patented Direct Ignition and Total Engine Control (http://www.electromotive-inc.com/)

Another nice one although not cheap.

Megasquirt has also been used by many with decent success. Any autotune setup can be a little risky in a boosted application though.

As Russell mentioned running that large of an injector you will need a system with decent injector driver setup to achieve any idle at all. However considering the circumstance idle quality may not be important eh?!

[rrussell]

What fuel are you going to run?

[Northwest outlaw]

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[rrussell]

VP Q or C16

You will have no problem meeting your goals with that fuel and injector combination.

Have you considered running E85 Fuel?

[Northwest outlaw]

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[Northwest outlaw]

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[rrussell]

was thinking about it how would that work with the EFI longer puls on the injector?

Yep you need to up the fuel delivery about 30% compared to petrol. The advantages would be...

improve idle running 160 lb/hr injectors
better throttle response
cooler running engine
cleaner burn, less carbon build up
a lot cooler charge a big advantage to a forced induction system
etc...

This is what we are running in Flybynights car and about three other cars I have been tuning on. The fuel is unreal for the money.

There is a chance we might have it locally in CDA at the pump. So that will help a ton.

[Northwest outlaw]

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[rrussell]

Thank you for the info now if you up the fuel PSI what does thet do to the injector does it raze the output on it so say a 160lbs flow say 160lbs at 45psi what does it do at 60 psi.

You would leave your fuel pressure the same and increase your injector pulse width about 30% for the needed extra fuel flow.

But to answer your question about raising your fuel pressure. If you are running 160lb/hr injectors at 43psi rail pressure then increase the rail pressure to 60psi the 160lb/hr injectors would flow 189lbs/hr.

[Northwest outlaw]

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[rrussell]

cool deal thank you for all the help im going to look into that class and start to read up more on this EFI stuff.

No problem;)

It looks like the next efi101 class that's close is California in November. That kinda sucks. Usually they have one in the Seattle area.

[Team Addiction]

No problem;)

It looks like the next efi101 class that's close is California in November. That kinda sucks. Usually they have one in the Seattle area.

Yeah flying to cali for the class does make it a little more cost prohibitive. Flight,car rental,hotel it starts to addup!! I believe the wife and I were in about $3000 travel cost. But that included Sea World LOL
If there was enough interest one could be hosted locally but there would have to be at least 15ppl IIRC

Looks like your in good hands :beer: Also look into Bens (Strader) book on EFI from Cartech it is pretty much the same book as the textbook for EFI101

[Northwest outlaw]

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[rrussell]

Well im making the jump so i should be setting up to EFI soon.

Cool!!! So what system are you going with?

[Northwest outlaw]

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[3258]

keep in mind that if you run the leaded gas (most gas over 100 octane) it will cause problems with o2 sensors. Methanol, and e85 are usually fine.

[3258]

As far as EFI classes, i think the better alternative is to build an ECU like MS and learn as you go...... as long as you have a base understanding of IC engines.

[98Z28]

There is a chance we might have it locally in CDA at the pump. So that will help a ton.

Is there anywhere in spokane to pick up E85?

[Jetblack]

I think Jeremy (THUMPN) has a line on that.... PM him to find out.

[rrussell]

"Grocery Boys" on 3430 N Crestline is where we have been getting it.

[Northwest outlaw]

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[98Z28]

And I paid $6.75/gal for 101 unleaded 2 years ago!!

[98Z28]

I've been talking with a friend about E85 (user 3258). He mentioned that E85 has a broad range of actual Ethanol content from around 70% to as high as 85%. How does this affect tuning the car, and once tuned, how do you account for the changes in ethanol content? E85 sounds like really cool stuff, but just wondering how safe it would be with the changing %.

[rrussell]

I've been talking with a friend about E85 (user 3258). He mentioned that E85 has a broad range of actual Ethanol content from around 70% to as high as 85%. How does this affect tuning the car, and once tuned, how do you account for the changes in ethanol content? E85 sounds like really cool stuff, but just wondering how safe it would be with the changing %.

There is a summer grade and winter grade ie. E70 and E85. You can purchase a tester for $15.00. This way you can check the content of the ethanol.
Its reusable and very easy to use. You just add water to the lower line then add your E85 fuel to the top line. Then shake it and let it sit for about 15 seconds. You will see where the two separate ethanol and gasoline. The line of separation is your ethanol content.

So far grocery Boys in Spokane has been very consistent E85.

Heres a pic.
http://i147.photobucket.com/albums/r312/rrussell_photo/0919092240a.jpg

[98Z28]

Awesome! You cant beat that for the price! Other than the fuel system upgrades, is there anything else someone should be aware of when switching to E85? Are there any problems with long term storage of E85?
Thanks for your help.

[rrussell]

Awesome! You cant beat that for the price! Other than the fuel system upgrades, is there anything else someone should be aware of when switching to E85? Are there any problems with long term storage of E85?
Thanks for your help.

Storage shouldn't be a problem. Its a very stable fuel.

[gregc]

I've been talking with a friend about E85 (user 3258). He mentioned that E85 has a broad range of actual Ethanol content from around 70% to as high as 85%. How does this affect tuning the car, and once tuned, how do you account for the changes in ethanol content? E85 sounds like really cool stuff, but just wondering how safe it would be with the changing %.

Unless you are on the ragged edge (extremely foolish for a street car), you won't have to worry about a thing.

I always find it funny how so many people bad mouth it because of consistency. They are usually the same ones who have no idea what their AFRs are... mix race fuel in a tank of other fuel... or sit there trying to figure out why their car sputters at part throttle.

I've been pretty much alone in figuring out how to tune my carb for E85. I've been told to just switch it over to C12 and be done with it. What everyone seems to forget is that I had just as much trouble on gas. I have finally figured out the issues (after 6 years) and have learned many intricacies of carb tuning. I've gone from changing main jets and air bleeds to grinding out new passages on the metering blocks and using lead to fill in holes.

As an idea of how the percentage of ethanol comes into play in it... I haven't checked the percentages in 3 months. As long as I can smell it, it will be close enough. The AFRs will tell me if I need a jet change and even then, it would never be required... only needed to maximize performance.

[3258]

I do know what my AFR's are via a wide band and EFI datalogging on methanol, and it is a race car so it does matter, 700HP NA sbc 14.5:1 compression in a dragster. EFI has much better control if you know what you are doing over the carb a.k.a controlled vac leak which will only get so good in all rpm/load range. I will say a person who led the pts for a majority of the season in S/P at my track was running e85. the variance in the ethanol % and the tree huggin' principal behind the fuel that is driving the rest of the commodities price up is a real turn off.