View Full Version : injectors in with no tune yet

Shift n Drift
09-20-2012, 02:27 PM
ok so im bout to put my s14sr back together, i have cams, a g20 throttle body, and 550 injetors.

heres the thing, i dont have the funds right now to get a tune on my power fc so im not putting the cams in yet. untill i get the funds, i will be using the stock cams and stock wc ecu like i did before i blew it. now i was wondering if i could use the 550 injectors now and when the funds come in, throw the cams in and get her tunned, dont know if it matters but its also got 9:0:1 87mm pistons in right now.

i just dont wanna go through the hassle of the intake manifold if i can get away with putting the injectors in now.

thanks for your input

09-20-2012, 02:41 PM
if you put the 550s in with out re-tuning it will run like shit if it runs at all. it will be extremely rich.

09-20-2012, 02:57 PM
If you don't have the funds, don't do it. It's as simple as that. A proper tune is essential if you want the engine to have any type of longevity.

Don't you go Florida on me bro. Oh wait...

09-20-2012, 03:02 PM
buy a 80 dollar tune from steve shadows


09-20-2012, 03:03 PM
If you have a PowerFC just program in the correct settings for your 550cc injectors

Apexi PowerFC FAQ (http://paulr33.com/powerfc-faq/powerfc-faq.htm#57)

09-20-2012, 05:25 PM
^+ 1 and don't run it without the tune. if the car would run with no tune, then with it being rich you could get fuel in the oil and cause damage to your bottom end.

09-20-2012, 06:43 PM
Save your money, get a good wide band and an fc datalogit, and idle tune it, then street tune it or pay for your own dyno time. It's depressing to hand someone that much money just to watch them change cells in a fuel map and fiddle with the timing. you'll thank me later. As long as you have the commander, you don't need the datalogit, it just makes things easier. Running rich is just as bad as running lean, especially on a fresh build/rebuild. Been there.

Shift n Drift
09-20-2012, 10:51 PM
word thanks a lot guys, so ill just run the stock injectors till i get 500 bucks so i can take it to a shop for the tune. damn, i guess ill slap all the stuff on in the spring, funds should be in by then, and the data logit, i have no experience handling that, i dont even no how to tune/fuck with the engine settings on need for speed. ill just pay some that has credibility of tuning power fc's and call it a day.

thanks again

oni jake
09-20-2012, 11:06 PM
You have a Power FC, you can adjust injector sizing on your commander and go drive around.

Formula = stock 370cc divided by 550cc = 0.67cc x 100 = 67.0%. Adjust injectors 1-4 to match 67%

Google your specific injector to find the latency.

Adjust MAF settings accordingly. Then be easy on your motor. Apexi thought ahead about their products and realized there are quite a bit of people out there who can't get a tune the day they install the ECU. Stock Power F/C tune runs on the rich side and pulls timing. Pretty safe stuff.

Oh ya, turn your O-2 sensor reading on in the Settings menu if you're using it.