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Discussion Starter · #1 ·
I'm looking to updgrade my MAF and injectors any good brands of those and what sizes. I'd like to go with 30# injectors, i am juicing my stang by the end of the year. i've already ordered a 75mm throttle body, looking at a bbk cold air intake, and i want to get the MAF and injectors. I was looking at the C&L 76mm MAF and 30# FRPP injectors. Anyone have any opinions on those and does anyone have anything for sale? Looking for BBK cold air intake, MAF, and injectors, let me know some prices.
 

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RIP Justincredible! God Speed
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With the mods you listed....30's would be way too big.

Here is a good bit of info on how to properly size injectors.

If you dont wish to read all the tech'y stuff...then just reference the chart at the bottom to see what size injectors you need for your application.

SIZING INJECTORS
While selecting the correct injector size for performance is something of a science, it can't be emphasized how important it is to get it right. As a rule of thumb, one may use the following simple formula that can be used is as follows:

HP / No. of Injectors X BSFC / Duty Cycle

To illustrate this, if we have a naturally aspirated V-8 engine producing 300 hp at the flywheel, we divide that figure by the number of injectors. Then we multiply that by a Brake Specific Fuel Consumption (BFFC) figure of .50. and divide that by a Duty Cycle of .80. On a calculator, those numbers would look like this:
300hp / 8 injectors = 37.5
37.5 X .50 BFSC = 18.75
18.75 / .80 Duty Cycle = 23.43 (24 lb/hr injector)
on any forced induction car, your BFFC is gonna be .60
so again, you numbers would look like this:
300hp/ 8 injectors = 37.5
37.5x .60 = 22.5
22.5 / .80 Duty Cycle = 28.125 (30lb/hr injector)
now let's look at a 4 Cylinder motor, turbocharged:
205hp / 4 injectors = 51.25
51.25 x .60 = 30.75
30.75 / .80 = 38.4375 round this up, and you will have 42lb/hr injectors
Now, if we need to convert those numbers to cc's for the import cars and some domestic cars, it would go like this:
The first example: 23.43 x 10.50 = 246 cc / min
The second example: 28.125 x 10.5 = 296 cc / min
The third example: 38.4375 x 10.50 = 404 cc / min
Also, if you know the cc of the injector on a motor, and want to know what that injector is in lbs/hr it would go like this:
The first example: 246 / 10.50 = 23.43 lb/hr injector
The second example: 296 / 10.50 = 28.1 lb/hr injector
The third example: 404 / 10.50 = 38.4 lb/hr injector
Well, this pretty much covers the basic's of sizing your injector for your engine. Without going into all of the science of how and why's, just use these number's along with your guess on your hp, and you will have the injector perfect in size for your engine...........Just an added note, you do not want your injector to have a duty cycle over 80%. An 80% duty cycle is just about perfect for any injector application. If you only want to use 70% of your injectors duty cycle, then use the above calculations, but instead of using .80, use .70 , you do not want to use an injector at below 55% duty cycle.



Injector Size Horsepower Range (flywheel hp), naturaly aspirated.
... 14 lb/hr ... up to 225
... 19 lb/hr ... 225-300
... 24 lb/hr ... 300-385
... 30 lb/hr ... 385-480
... 36 lb/hr ... 480-575
... 42 lb/hr ... 575-670
... 50 lb/hr ... 670-800

The above injector hp ratings are for high impedance injectors only.
 

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Discussion Starter · #3 ·
ok so if my car is 230 or so at the flywheel and i plan on getting it up to 300 this summer i could buy 24# injectors right now right and they'd still work with my other mods, i also am getting a bbk cold air intake, bbk 75mm throttle body, and trick flow track heat intake.
 

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I'll suggest you after you get full exhaust done, and since you plan on doing upper and lower intake, save up some more and get a cam, and a pair of cylinder heads off of an 97 1/2 or higher 5.0 explorer. Clean them up and if you can port and polish them. With that alone, you'll be really close to 300 HP. The 19# injector will still work, but it will be working close to 100% of it's capacity. You can upgrade the Fuel Pump, injector and MAF at a later time.

Do some more research man, you'll see great response from your 5.0
 

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RIP Justincredible! God Speed
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ok so if my car is 230 or so at the flywheel and i plan on getting it up to 300 this summer i could buy 24# injectors right now right and they'd still work with my other mods, i also am getting a bbk cold air intake, bbk 75mm throttle body, and trick flow track heat intake.
Dont take this the wrong way...No matter what bolt-on's you install, your not going to see 300 hp @ the flywheel with the stock heads. (excluding nitrous or a supercharger/turbo).

I agree with "stang94"....
Your 19's should be good for any and all bolt-on combo's as long as your running your current heads.
 

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Discussion Starter · #6 ·
no, when i do it, i'm doing it right. there will be a set of twisted wedges on there. thanks for the suggestion though.
 

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OK, then that make better sense. But you wont need Injector and MAF until you do heads and CAM. Save up get the Heads and Cam first, and take it easy on the car until you can get injector and MAF.

PS: In your case you might as well save up and get the top end kit instead. You'll get more stuff, new rocker arms, timing chain and gears, alot of stuff comes with the kit.
 

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Discussion Starter · #8 ·
thats probably what i'm going to do
 

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dont buy "the kit" I was going to do that and woody and darrell put me together a top end for about the same price with some better parts....do the trickflow heads....do the track heat intakes .. scrap the cam and go custom grind and I would reccommend harland sharp rockers.....and jay allen is a good guy to deal with and rumor has it one of the best if not THE best... I can say good things about dealing with him but my cam is not in the car yet
 
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