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Discussion Starter · #1 ·
I want a pretty low IDCs and have it be pretty reliable w/o getting maxed out. I originally was going to go w/ the STI injectors, but was told by a couple people that the IDC would be somewhere around 91% with the stis. So I was thinking about the PE 650cc or larger. Anyone have any input? Am I worrying about nothing or should I be fine w/ the STi injectors? Thanks in advance.
 

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That sounds about right if not a little higher with the PE turbo. Go with the PE 650cc units. Much safer, and you won't have any idle problems so long as you have aftermarker engine management.

Ken
 

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So STI will max out if used with a PE and 20PSI??
why if will run 91% ,,not maxed out,,will you want more??
Isnt the max you will use in the STI 91%??So,,isnt it made to run that high??
Thanks
Tuca
 

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hmm....so you need injectors larger than the STi's to run more than 20 psi? doh! that'll set me back a few more hundred ;) time to start saving up
 

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I don't think so. I have run in excess of 22psi with my VF22 at the track and never logged higher than 85% IDC. I'd feel comfortable pushing these injectors to 90% IDC, and maybe even a little higher.

The STi injectors can handle anything that the PE turbos can dish out IIRC. The PE1818 is NOT a big turbo. It's actually the same size as a VF30, and while it does have revised internals that allow it to flow much more, I don't believe it is capable of maxing out 565cc injectors unless you push it out of its efficiency range. Now if you are thinking of eventually moving to one of the big garrett setups such as that being developed by TXS, then yes maybe consider running bigger injectors.

Besides which, if you want to be running 20+psi MAP on a daily basis then injectors are going to be the least of your concerns. You are going to have to pay attention to the pistons, rods, and head gasket to enable them to repeatedly withstand the resulting cylinder pressures I think.


-Pace
 

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Actually Pace the PE is quite a bit bigger than the VF30 on the compressor side. It will absolutely kill it on power and not much laggier. It can come close to maxing out the injectors at 22 PSI but since you're running race fuel, it's not quite at 95%. On pump gas you will get close to that point but still safe. Highest you can run on 93 octane is 20 PSI with the correct supporting mods.
 

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And the PE1820?will it max out the STI injectors??
I want to sqeeze all power that i can,,so i want to use the more boost as possible,,will the STI injectors max out with a PE1820?
What is the solution?PE injectors??or there are bigger STI ones?
Thanks
TUca
 

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Discussion Starter · #8 ·
Ok, I'll probably go w/ the PE 650s just to be safe. Hey Dan, can you get me prices on this? The only vendor I saw who carries them ATM is vivid and I don't wanna buy it from them.

There are no larger STI injectors to my knowledge. You can get the PE 650s or 800cc injectors. Then I believe Bosch has 700 and 1000cc injectors.

Thanks for the replies so far. Anyone else? ;)
 

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You will need to consider what EMS you plan on using. Some solutions are not compatible with the really big injectors. Make sure you get good quality units. Anything from PowerEnterprises should be fine, but beware of cheaper brands that are priced below the STi units.

-Pace
 

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Discussion Starter · #10 ·
I will temporarily be using the unichip until autronic releases their ecu. I will be getting good quality units...no question. ;)
 

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650cc no problem. Pricing is on my website but I'll try to cut you a break if you're buying the turbo or other things. Crazy Al has the STi injectors and I don't think he maxed them out on his 1820 although I think he came pretty close and not sure if he pumped up the fuel pressure or not. PE has both 650 and 800cc although the 800CC will not idle very well with the stock 2.0 liter displacement.
 

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So GOd,Its the PE injector better than the STI if in Use with a PE1820 and a 50 NOS shot?
does the NOS affect anything?
Thanks
Tuca
 

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I was planning using NOS only at a Drag track.
Here is very rare drag races and they happen in 4 in 4 months =(
I was thinking that only a 50 shot or less of NOS with the proper UTEC map tuned for it,,wont cause damages,,maybe to my tranny.
But how much is a new tranny??
i dont think i will break my engine if using NOS very rarely.
What do you think?
Tuca
 

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If you are using a dry shot, then yes bigger injectors would be smart as you will need to tune your EMS for extra fueling. However most of us that employ Nitrous on the WRX are using a wet shot, where the extra fueling is supplied though a fogger nozzle. In that case I don't think you will need bigger injectors (than you would without the Nitrous). An uprated fuel pump is always smart though.

-Pace
 

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We here use a Wet kit,,the solenoid sends fuel with the NOS.
isnt it safe to run sometimes??
I know my goal of 300WHP will be achieved,,but why not make 1 second better quarter mile times by spryaying only for 4 and 4 months 3 runs for the quarter.
isnt that safe?
Tuca
 

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Discussion Starter · #19 ·
Say if I still wanted to use the sti injectors. Would a fuel rail kit be of any help to prevent high IDCs? Or am I smoking crack? :p
 

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Hybrid-X said:
Say if I still wanted to use the sti injectors. Would a fuel rail kit be of any help to prevent high IDCs? Or am I smoking crack? :p
Put the pipe down. ;)

Seriously though, I think upgraded rails are more intended to keep a consistent and equal flow of fuel across all four injectors. I don't see how they would lower your IDC unless the stock rails are so restrictive that the computer increases the IDC to compensate for starvation of fuel to the injectors. I don't think the WRX rails are quite that bad though.

-Pace
 
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