General 2G How much can stock injection take?

[Flying Cowboy]

Runnig on a .50 turbo, big intercooler, high flow exhaust manifold, 3" downpipe, 3" exhaust all the way out, stock ignition, stock ecu, stock injectors, stock cams, stock rods, stock pistons, forged crankshaft... Just a FuelTech wideband to watch air/fuel ratio.

My question is if one of you guys have any idea on how much boost the stock EFI can take? Or is it just too risky not to improve to a FuelTech or ECMLink?

 

[pauleyman]

You should already be out of fuel. The issue isn't just "tuneability". It's that the stock ECU cannot run larger injectors all on it's own. That is how you get more fuel as demand requires it. Once you reach 100% duty cycle there is no more. You must upgrade to a larger injector and you need something to "tune" it. The tuning part of an EFI system comes from its ability to adjust under different conditions and not simply add more fuel. The add more fuel part is simply the most basic need of a modified car. Once you add lots more air as you have you need more fuel.

 

[Flying Cowboy]

I do get what you're saying. maybe a I didn't expressed myself well.

On a stock turbo, do the injectors run on 100% of their capacity?

Because my first upgrade (I know that was not the ideal) was a bigger turbo. It ran for a while, with more boost, and a little lean (not the ideal as well), til the timing belt jumped and the pistons hit the valves.

Now I am rebuilding it, but still don't have the money to buy an new EFI. Just trying to make sure that I can drive the car a little more before upgrading it (injectors and EFI)

 

[pauleyman]

I do get what you're saying. maybe a I didn't expressed myself well.

On a stock turbo, do the injectors run on 100% of their capacity?

On a 2g stock t25 probably not.

Because my first upgrade (I know that was not the ideal) was a bigger turbo. It ran for a while, with more boost, and a little lean (not the ideal as well)

not just not ideal. It's unacceptable.

, til the timing belt jumped and the pistons hit the valves.

Now I am rebuilding it, but still don't have the money to buy an new EFI. Just trying to make sure that I can drive the car a little more before upgrading it (injectors and EFI)

you get the boost as low as it will go (wastegate spring pressure) and see where your AF ratio is. That will determine what you can and cannot do. There is no other way if you intend to leave that turbo on it short of no boost depending on what boost control you have. You did not tell us what wastegate it uses.

 

[Flying Cowboy]

Unacceptable. NOTED.

I run a AutoBoost W30 wastegate.

Here in Brazil is really difficult to build something decent on low budget.

So as soon as I make the car run again: new EFI and bigger Injectors.

Thank you for your wisdom and time!

 

[pauleyman]

Unacceptable. NOTED.

I run a AutoBoost W30 wastegate.

Not real easy to run with no boost at all so you'll have to run at wastegate spring pressure.

Here in Brazil is really difficult to build something decent on low budget.

So as soon as I make the car run again: new EFI and bigger Injectors.

Thank you for your wisdom and time!

You mentioned you have a wideband sensor. What did it read at WOT?

 

[Flying Cowboy]

At WOT, wideband was reading 0,84

 

[pauleyman]

What does that mean? 0,84????

 

[danl]

probably 0.84 lambda which is like 12.3 on gas. Though I believe Brazil uses ethanol.

 

[Flying Cowboy]

0.84 lambda, that's correct. But running on gas