weezyfbayba

havent dynoed my car but im guess between 360-380..

trd07tc

iTrader: (-1)

Have to know the power otherwise this thread cant go anywhere

Ace83

iTrader: (6)

well the thread is about if he has enough fueling.. with a boost gauge and datalogging that should be enough to figure out

trd07tc

iTrader: (-1)

I know what the thread is about. He is running out of fuel at 13 PSI. How much power is that? WE HAVE NO IDEA.

Power and duty cycle go together. Not boost and duty cycle

Ace83

iTrader: (6)

His tuner said he is running out of fuel. He didnt have the injector duty cycle data to show is 100% opening nor said he was leaning out. So without a horsepower data, we can figure out by his duty cycles

Boost and duty cycle will go together too, we are not comparing his setup with another another one.. So that means his setup on 9 psi will have lesser injector duty cycle than 13 psi on his setup.

RusWolf

iTrader: (3)

OP C.T. you mean Connecticut right ? call Vinny Ten in Long Island, NY and find out if he can tune AEM EMS, hes pretty good at tuning he tuned my car on hydra.

BlckdOutTC

iTrader: (1)

700cc injectors should not give you any problems at all on only 13psi. i think up to 17 or even 18 you should be good with them. this definitely sounds like a tune issue. if you do go that high again a fuel return would be a good/safe investment, again, at that psi

ElevationTC

he needs to rescale the map lol! ur tuner fails

Sent from my Droid using Tapatalk

BoostedBeastBox

iTrader: (6)

^ pm"d

And thanks for all the input fella's In the mean time im gonna see if i can get that free dyno for shts & giggles. ill keep this thread posted

DezodDon

Holy crap this is the second time I am typing this because the first time my browser crashed.

There are a few things we must take into consideration when we look at this guys setup.

1. 16 psi on a t3/t4 and 16psi on a GT35R are similar in pressure only. The airflow at that boost level would be greater on the GT35R necessitating more fuel flow. So it would be difficult to really compare the two.

2. Why do we use a return fuel system? We use a return fuel system to control pressure and in some designs flow more fuel.

The stock fuel system uses a regulator to control the fuel pressure at a static range. 44-50 psi. This is fine for NA because there is no strain on the fuel injectors and under WOT conditions there is 0" hg (vacuum) in the intake manifold. When we boost a car we are introducing positive pressure to the intake manifold. This has an effect on the fuel pressure. For every pound of boost you add to the intake tract you effectively reduce the fuel pressure at the nozzle of the fuel injector by one pound. Now, the fuel pressure in the rail is still the same this is not effected. However when the fuel injector opens to inject fuel into the port it has to fight against whatever positive pressure is in the port this has the effect of reducing the available fuel pressure in the port. There is a lot of engineering and math behind this so for all intents and purposes the effect is like having less available fuel pressure.

Think of it this way. You are riding your bicycle on a calm day no wind. It is easy to peddle no problem everything is great. This is what the fuel is doing in your port under NA conditions. Now, go ride your bike on a windy day, into a 10mph head wind. You have to peddle harder just to maintain the same pace you were on the nice day. This is fuel in a port that is boosted.

So when you are using the stock fuel system with a regulator that is incapable of changing to the meet the demands of your fuel needs you end up running out of fuel easily. If you have a base fuel pressure of 50psi and you add 16 psi of boost to your intake manifold you can subtract 16 psi from your base fuel pressure. Those 750cc injectors are now effectively running on 34 psi of fuel pressure.

If you use a return fuel system you get the benefits of having a dedicated fuel feed line, a rising rate fuel pressure regulator at a ratio of 1:1 so for every pound of boost you add the manifold your regulator ups the fuel pressure by one pound of fuel pressure maintaining your base fuel pressure that you needed to keep the fuel delivery accurate.

Now, I'm not saying this is your only issue. It would be wrong of me to say that without even looking at the car.

If you like you can send me a copy of your calibration and I can look at it and let you know what I think. If you can get some data logs that will help as well. I think I was trying to help you through Email and I don't think I ever heard back from you.

This link is a good calculator to figure out roughly what size injectors you would need. It's at the bottom of the page

http://www.rceng.com/technical.aspx?UserID=4756793&SessionID={d7xCCGHJtPS8crTGwy{

To give you an example if I wanted to make 500 CRANK hp on 93 octane gasoline with a 4 cylinder I would need 1075cc injectors. Food for though.