What size fuel injectors would you rec?

[1SickFox]

Hello, I'm just finishing up buying my parts for my combo and i'm just trying to get some educated guesses on what size fuel injectors i'm going to need to purchase. I'll list my combo. I'm going to keep my pullies on the blower stock. I only want 5-6lbs of boost. My goal is to reach 350rwhp give or take. I don't want 400+ though. Does my combo sound about right to reach that goal? What size injectors? Thanks!!!


Combo
306 stock block
TFS heads
1993 Cobra intake
F303 Cam
Vortech Sc-trim - stock pullies(5-6lbs)
BBK 70mm TB
AFM Powerpipe

 

[rednotch88]

30-36lbs for now. you up that boost in future you might be looking at 42's with some more mods of course.
You can probably get away with maxing out some 24's,but that's dangerous get some 36lbs for now.you'll be happy trade them in for some larger ones later.

 

[uedlose]

I would just get the 42# and be done with it.

 

[Cobra912]

I would just get the 42# and be done with it.

I agree. I bought 30's for my 331 thinking I wouldn't upgrade..low and behold......I bought a blower.....I had to shell out more cash for the 42's.

 

[1SickFox]

Thanks for all the imput! Aren't 42's a little bit over kill though? I don't plan to up the HP because this is just a nice driver. My neighbor has a nice used set of 24lb and 42lb FRPP injectors though. So 42's i could get cheaper. Would they cause any problems running that big of an injector?

 

[Foxfan88]

Thanks for all the imput! Aren't 42's a little bit over kill though? I don't plan to up the HP because this is just a nice driver. My neighbor has a nice used set of 24lb and 42lb FRPP injectors though. So 42's i could get cheaper. Would they cause any problems running that big of an injector?

are you planning on getting the car tuned?? if so then dont worry you can run a larger injector than needed. as long as the car is tuned properly it will work great.

if not you could try running a maf "calibrated" for 42s, but i highyl doubt the fuel delivery will be in check.

i myself highly reccomend a good tune with larger injectors, dont use an FMU. they work but they are not ideal.

 

[1SickFox]

Yep the car is getting tuned. I never believed in FMU's ha. So i could run 42lb'ers and be fine with a tune? Thanks again.

are you planning on getting the car tuned?? if so then dont worry you can run a larger injector than needed. as long as the car is tuned properly it will work great.

if not you could try running a maf "calibrated" for 42s, but i highyl doubt the fuel delivery will be in check.

i myself highly reccomend a good tune with larger injectors, dont use an FMU. they work but they are not ideal.

 

[final5-0]

If you go custom tune ... which I would advise

You'll have no need for elevated fuel pressures and all of that mess
thus
Your tuner can make those 42 work just dandy

When you tune with the pcm

You gotta think just a bit different than the masses
and
All those ideas from back in the day when folk used

Calibrated meters with matching injectors
Adjustable fuel pressure regulators
Spark control by dizzy twisting

I'd find a Pro Tuner with Good References and ask him for his thoughts

Grady

 

[BlownFiveLiter]

I went straight for the 60's, but I'm planning more boost. I'm looking to go somewhere from 9-12psi on mine.

 

[7upstang91]

Both 36s and 42s would work. I just put down 388rwhp with 42s so they should work fine with a tune.

 

[Foxfan88]

Yep the car is getting tuned. I never believed in FMU's ha. So i could run 42lb'ers and be fine with a tune? Thanks again.

yeah get the car tuned and all is good.
i am running the combo in my sig without the turbo yet.

i'm using 42 lb injectors now. and have tuned it in the EEC, car runs and drives like a stocker. you wouldnt ever guess it had oversized injectors on it.

actually 24s would be perfect for it, but since i am putting a turbo on it i am using the 42s, dont want to mess around and get more injectors.

 

[Grn92LX]

42

 

[ID89GT]

Go big or go home. Get some 160 pounders

 

[FastDriver]

I concur... 160s FTMFW!

 

[FastDriver]

It sounds like you can get 42s easiest, and it's nice to have plenty of room to grow.

36s would work fine with room to grow, too. 30s would be stretching it, but would also work with your given combo.

Take the best deal you can find while weighing in the potential that you will want more power in the future.

Chris

 

[87 GT]

Get it tuned!

I'm running 30 pounders on a 330 hp engine. They were "turned down" to about 50% of their capacity when I had this combo dyno tuned. 24s would have worked fine, too, but also would have to have been adjusted to perform at their best.

The most important thing for you to do is to have it dyno tuned by someone who knows what he's doing. You can't just bolt together an EFI engine and go. ALL of them would benefit from a tune. Anyone who thinks you can just mix and match components and end up with air/fuel ratios in the correct range is kidding himself. Get a tune.