[GinEclipse]

So I'm kinda figuring out or have been figuring out that the aftermarket support for this car is ki da crap. I was wondering if I got bigger fuel injectors without a turbo or super charger and then get it tuned. Will anything bad happen to my engine like the crank shift. I have a aftermarket intake and don't know if the full ratio problem will be solved with that alone. Also if it is possible with out and forced induction what injectors should I get and where can I find them. I saw some one wanting to get 563CC injectors but someone else said it won't last 3 miles without a tune but in that thread he also stated that he was already building is super charger. So I'm at a lost, I'm still learning please lmk thx.

ps.Also I barley know anything about injectors.

 

[Associate00]

If you upgrade your injectors without getting a tune, you'll run incredibly rich and possibly hydrolock your engine. The stock injectors are, I think?, 300CC or so. There's really no reason to put in bigger injectors, UNLESS you're going FI. Please, don't do this.

EDIT: The reason you need a tune is because your computer is tuned for 300cc injectors and cannot/does not know that you've got 563cc injectors in. In short, I cannot say whether this will blow the welds on your intake, but i know it'll definitely hurt the wallet at every fill up lol.

 

[Sabertooth^2]

The issue is entirely that the engine knows how long opening an injector for to give a certain amount of fuel. If you change to an injector that gives a different amount of fuel in the time it is programmed to leave it open for, it'll be wrong.

So when you go to a larger injector, in the tuning the time the injector stays open for is lowered so you still get the same amount of fuel that it needs to run right. This is also why when you go with large cheap injectors with long latencies that you run into idle issues. They can't open and close fast enough, giving too much fuel, so you have to raise the idle higher to compensate (as higher idle requires more fuel)


As for crank walk, that was an issue on the Evo 1-4 and early Eclipse 4G63 engines. That was sorted out by changing the thrust washer design, moving the oil feed to them to actually align with the thrust washer opening (they had a design issue that limited oil to the thrust washer) and low oil pressures which didn't feed the thrust washer much at idle.

 

[TheSlow4g]

Without forced induction I don't think you'll have much to benefit from bigger injectors unless you plan on doing that later on, but if you are interested in upgrading, I do have a hookup for getting the 565cc injectors. You'll just have to be sure to get it tuned properly after installing them.

 

[GinEclipse]

Thank you all for the help so I see that if I get injectors tors I will need a tune and there is no reason to get them u less I am looking it to forced induction

 

[Sabertooth^2]

Correct.

Right size injector for the job is best. Using 565cc injectors to flow 250cc wont add any power.

 

[GinEclipse]

I have another question that might be repetitive because I saw it on another post. But I saw someone say to get new headers Intake a new underdrive pully and a tune. I did some research and was looking at RRE catless headers but the underdrive pully will that add any HP or will it make my engine a lot smoother cause I read it reduces vibrations inside the cab?

 

[Sabertooth^2]

The underdrive adds crank flex, so you get a bit more crankshaft main bearing wear. It's a crankshaft vibration damper. The stock one dampens, the underdrive does not.

You will notice no cabin vibration difference, because that's not what it's for or related to.

It will add about 10hp peak.

 

[TwilsonD7]

What good is more fuel without more air? No reason to do this. The cat runs rich from factory, installing larger injectors would just flood the engine and waste fuel