If I swap to a VF39 with stock (07') WRX injectors do I have to worry about maxing them out? At what percent will they be running at?
I was looking at getting some STi injectors for our model year just a few weeks ago for a future upgrade, but when I researched it, the WRX injectors are actually slightly better then the STi's... I think Shibb's might know more on this, and I may be completely wrong.
Depending on your tune (type of gas, tuner's style), you can max them out. Talk to your tuner. You should be fine with stock wrx injectors. STI switched from side feed to top feed in 07. 07 STI's came with the same blue injectors that were in the 06/07 wrx. These injectors flow slightly more than jdm sti pinks.
i have a vf39 and im using 565cc injectors and i have been told they are the right size for that turbo... if that helps you out at all
I'm not quite sure what point you're making here. If he has an 06/07 WRX, he already has top-feed injectors that flow at 565cc anyway (maybe more). These are the exact same injectors used in the 07 STI, which is running the same thing as a VF39. His injectors should be OK as-is.
don't you should on me! the point is that the reassureing poster is saying: and he is not running the same short block, so this is little assurence. Idget has the best answer yet: your Cycle duty percentage will depend on the tune. you could try to run pig rich and max those puppers out, or you could run lean on an "AGRESSIVE" tune and "MAX OUT" that vf39... and possibly run into 105 percent cycle duty... it's all in the tune. If you want to push every ounce of power out that vf39.. get some 630cc....
I'm not even sure that you're speaking english here. Look, any time you're doing a modification like this, you should reference your ideas with your tuner. However, for about 98% of the Subaru community running a VF39, 565cc injectors will be fine. If you really start pushing it and maxing the Injector Duty Cycles, your tuner will probably recommend upgrading the injectors at that time. To be honest, with something like a 39, I wouldn't really worry about anything that much bigger.
And ok guys, settle. VF39 + 565's on pump will be fine. As for IDC's: IDC's will vary depending on AFR, MAF scaling, and injector scaling. IDC's are a calculated value, so they don't really mean ****, other then as a baseline for when you are running out of injector.
This thread is bordering on stupid and foolish. Keep it to pertinent information regarding the situation presented by the OP. As for my 2 cents. You are asking if this setup will work. It will work fine. Plenty of people have run 565cc+VF3X turbos for as long as I can remember with good results. If it wasn't good results, they wouldn't put it as a stock configuration for a factory car. Beyond this post, there shouldn't be any more posts till the OP updates this thread with more information. Any further bickering and crapping on this thread will result in punishments. When you ask someone for help with a situation, you don't want half a dozen people to hop to and take a dump in your lap, so don't do it in this thread either.
I've got the idea thanks for the input everyone, I'll post some numbers when I'm done with the tune, this week?