beauphus

thinking of doing injectors. collective wisdom has told me to get 550cc. stumbled across this calculator and it claims i should be running 650cc +

http://www.witchhunter.com/injectorcalc1.php4

same here

http://www.rceng.com/technical.aspx

thoughts?

lowprofile

My guess is that you are not correcting for fuel pressure. These formulas assume 43.5 psi while we have ~65PSI at WOT. At the bottom of both links is a correction table for PSI.

beauphus

got it! understood. 550 is the magic number

E55Bullet

Any updates on the injectors?

e55amgrocket

i put the 550cc ones in my car along with some other things but havent got a chance to dyno it to see what the injector duty cycle looks like or anything else.

LOCO 05' E55

Did you retune afterinstalling them??? i had them on my car and had to remove them..

930chas

I bet you are super rich. I would pull them out and run stockers until you see Jeremy in February.

LOCO 05' E55

+1

930chas

Luis, you have been there done that with the 550s! lol

KLR CLS

I was running into the 9's on the afr's until it was tuned right by Jerry at EC. Now its running 11.5's to 10.8's and perfect idle and throttle response. Definately need to tune with the 550's.

E55Bullet

Is it worth doing?

loungn14

DEFINATELY if your modded. We have the ability to see injector duty cycle through our dyno and see very scary things on decently modded E55's at the top of 3rd..

and yes, you absolutely need a retune for the injectors. Too much fuel can be a bad thing as well...

E55Bullet

Ok, next question, can you drive say a couple of hours on the road without a tune for the injectors to get tuned?

LOCO 05' E55

All depends what mods you are planning on adding in the future, can be a great supplement, as well as if you plan on doing frequent 130mph + blasts... Its one of the weaker links in our cars and doesnt hurt to do the swap..550s are overkill IMO- SLRs have proven great results with less cc's but do cost more $$..

KLR CLS

In my opinion people are stupid not to run them. The cost for extra peace of mind is well worth it. Tuning 101 says more boost, more fuel. The only reason the stock system keeps up is the abnormally high FPR we run. Injectors running 90% and above IDC is a bad thing, and will lead to popped motors on highly tuned cars. I drove for some time without an ideal tune. Main concern running too rich is fouling plugs or O2 sensors, as well as less power. With them in I am running huge power and know its super safe on the fuel side.

AgSilver

SLR injectors have 6 ports as opposed to the standard 4 ports. Better spray and atomization.

chawkins2001

How many LPH's do our fuel pumps run at? Big squirtters with a bigger fuel pump and some nice fat fuel rails make for a good precautionary meausre when you start running high HP. Love the sound of them ticking away under the hood

e55amgrocket

I'm sure im running super rich now but i did a few other things to get more air in now so with the old tune and the new injectors i think it safe to drive around town now. I did everything thinking he would be here Jan 20-21st but that didnt happen Hopefully when he tunes it he can get everything to work together happily.

KLR CLS

Even with the EC box tune for injectors I was running rich. Be sure you are doing a dyno with a wideband to ensure you get the AF where it needs to be.

e55amgrocket

Did you re-install them when you had it tuned? I've only put about 80 very easy miles on the car since i put them in. Was it a problem with Jeremy not being able to get the AFR's leaned out or why did yall have to take them back out? Just curious

930chas

Luis hasn't been tuned yet. Also, I would ask Jeremy about tuning with the 550s just to get his impressions.. and definitely swap your stock ones back in for now.

e55amgrocket

I emailed him about needing the re-tune with the injectors and he said it wouldnt be a problem so hopefully everything will be ok with it.

930chas

Cool man. That is good.

blackbenzz

How are you guys without meth controllers determining your IDC?

LOCO 05' E55

I had 550s on my car and part throttle was affected as well as at WOT.. Car would bug and hesitate. AFR's would not go over 10 on 3rd gear pulls lol. So I immediately removed them since Jeremy wasn't coming to my area at the time and temps were dropping so I was not going to race the car on 550s, no way!

So my next thing is Either SLRs or Bosch 450cc's... If he told you he'd tune the 550s then great.. but after some research 450s should cut it for me..you should remove them if you are going to keep driving the car before you get re-tuned..