EFI injector size

[phunt]

Was wondering what size injectors people are using on a 3.5L with ITB’s and EFI. Looking to support 100 HP per liter

[Tom_in_NH]

To support 350HP, you'll need 175 lbs per hr of fuel, assumming a .50 BSFC (Brake Specific Fuel Consumption. A .50 BSFC is consider average for a performance N/A engine.

So, 175/6 (6 cylinders) is 30 lbs per hr per cylinder. Mind you, this leaves no head room.

[TimT]

Use a calculator like this for find what size injectors you need..

Injector sizing calculator

https://www.injector.com/cart/pc/Bosch-36-lb-hr-380-cc-min-Fuel-Injector-44p40.htm"]36# injectors[/URL]

[safe]

Yes, 400cc and over. Get some modern Bosch motorsport injectors that are stainless and compatible with ethanol (e85). Too big is not really a problem.

[phunt]

Thanks all.

[winders]

I recommend talking with Injector Dynamics. They have the best product on the market...

Injector Dynamics

[Jeff Alton]

Based on their website they sell Bosch injectors. Great products.

There are other very high end options available as well.

We have had great results with https://deatschwerks.com/en-ca/collections/injectors as well on varying motors. Same with their pumps.

YMMV

[winders]

Originally Posted by Jeff Alton

Based on their website they sell Bosch injectors. Great products.

There are other very high end options available as well.

We have had great results with https://deatschwerks.com/en-ca/collections/injectors as well on varying motors. Same with their pumps.

YMMV

No....they partner with Bosch to design and build their own unique products.

"The ID1050x is the evolution of the ID1000, and the latest addition to the X-Series. It is the most recent offering from the partnership of Injector Dynamics and Bosch Motorsport, and is the result of lessons learned during development of the ID1300x, and ID1700x. Like the ID1300x and ID1700x, the ID1050x is not a modified production component. It is a built to spec motorsport injector, offering optimization of critical operating parameters important to you, the motorsport tuner. "

[phunt]

Thanks again everyone my problem is the injector I want to use only comes is 100pph or higher. My issue is the minimum pulse of it is to much for idle. Too much fuel delivered to fun smooth. I will most likely end up with a 48pph LS short size EV14 connector. Over kill. But

[TimT]

I will most likely end up with a 48pph LS short size EV14 connector. Over kill. But

Pick an injector that is readily available, a 36# injector gives you a bunch of headroom on duty cycle.. The Marren calculator use 80% for sizing, other calculators have even more variables to add..

You never mentioned if you need a high or low impedance injector... The controls on modern EFI systems can handle idle on over sized injectors

[phunt]

I am looking to kind of limit the flow so I was looking at high impedance. Plus high should run cooler. I am using Hal tech 750 ecu iac tp iat map and dual o2. Plus the 750 has a barometer. I understand that the system compensates a lot of factors for smooth idle. But if the minimum pulse of the injector is to much it will run too rich

[safe]

Originally Posted by phunt

But if the minimum pulse of the injector is to much it will run too rich

NOT an issue. I run 1000cc (~100pph) injectors on my 2 liter 924. Most of the time the injectors are barely opening.
Lots of people runs double that on small 4 bangers. Good injectors, a good EFI and accurate specs on the injectors in the EFI.
But its really unnecessary, to run bigger injectors than you need. There are a myriad of injectors that will suit your needs.
High impedance or low has nothing to do with flow, its mostly old tech and new tech. You need low impedance injectors when you are going really crazy.