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Old 12-05-2012, 12:33 AM   #1
'08WRXRider
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Default HELP: What Size Fuel Injs/Pump Should I Run To Reliably Run Stage 2.52 Indefinitely?

My car is a 2008 WRX. I'm preparing to go Stage 2.52 (then, 3.52 down the road) & I can't afford to buy another engine anytime soon should this one sustain damage from lean condition upon upgrading.

So I'll be upgrading to the IHI VF-52 turbo in favor of my stock Mitsubishi TD04. With the other Stage 2 mods (Cobb AP, Invidia Catted DP, AEM CAI & tune) & running California's crappy 91 octane fuel, my research suggests I can expect approximately (I know all dynos read differently & these numbers, at best, ballpark) 275AWHP (320HP-ish at the crank) give or take.

When I do the necessary calculations to determine the appropriately sized fuel injectors for that amount of power, I always come to the conclusion that larger-than-stock injectors are necessary to safely & reliably achieve it. However, some sources suggest that the stock injectors will accomplish my goals at Stage 2.52. This has left me a bit confused & with the upgrade on hold until I can get clear, conclusive answers as to what injectors & pump combo I need to run to reliably run Stage 2.52 indefinitely.

I've been told that the stock fuel injectors on my car are rated at 565cc/min (Is that right?). I've, also, been taught not to push Injector Duty Cycle (IDC) past about 90% for any significant amount of time or the injector doesn't actually go off reliably at the end of its duty cycle. So, when you push the injectors past that point you get, essentially, 100% IDC (on). If these things are true, then it seems to me that upgrading the injectors & fuel pump (to keep up with them) are a must to really reap the benefits of Stage 2(.52) or above & maintain some real level of reliability.

BTW, my calculations are based on: desired engine power of about 320HP, 4 fuel injectors, injector duty cycle of 80 - 85% ('ideal' as recommended, for example, by RC Engineering @ http://www.rceng.com/technical.aspx), Brake Specific Fuel Consumption (BSFC) of 0.65 (for a Gasoline powered, turbocharged engine running boost of 1.3 - 1.4 BAR/18 - 19 PSI).

Based on these calculations & using the stock injectors, I only get 281.5HP at the crank. Well short of the 320HP I'm looking for.

All that considered, what size injectors & pump should I use to achieve my goals & have my engine last?

Thanks for any help/answers to these questions you can provide. I need to know the right way to go here so I can move ahead.
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Old 12-05-2012, 12:59 AM   #2
pet3r
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ID1000s would be more than enough and are rock solid. Any of the aftermarket pumps will be sufficient as well. D65C will be a direct drop in and give adequate fuel for your power.

Last edited by pet3r; 12-05-2012 at 01:33 AM.
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Old 12-05-2012, 01:44 AM   #3
UK-Wagon
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Do smell I a Troll thread?

stage 2.52 and stage 3.52????

No, you do NOT have a Mitsubishi TD04 in youre 08 unless you did some kind of a swap to a 06 WRX setup.

Do more homework, or if this is a Troll thread..... try harder next time
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Old 12-05-2012, 07:40 AM   #4
jaxscuby
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well 08 came with factory 535/550, the dark blue topfeeds.
but for the power output you want you at least need 650s.

a 255lph is enough of a fuel pump. not to mention cost.
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Old 12-05-2012, 08:55 AM   #5
ah2049
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Quote:
Originally Posted by UK-Wagon View Post
No, you do NOT have a Mitsubishi TD04 in youre 08 unless you did some kind of a swap to a 06 WRX setup.
The 08 ran a modified TD04. And if I'm not mistaken, it's the same turbo that's been in the WRX since 02, just modified for LGT layout of the 3G cars. As to who is was made by, I don't know, but at that point I think it would just be arguing semantics...
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Old 12-05-2012, 08:59 AM   #6
mechatricity
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I had to google it. Stage 2.52 is a Torqued Performance map for a VF52 on an 08 WRX.

OP: don't ask US what you need for SOMEONE ELSES map. Ask Torqued Performance.
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Old 12-05-2012, 09:27 AM   #7
Leafy
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Quote:
Originally Posted by UK-Wagon View Post
Do smell I a Troll thread?

stage 2.52 and stage 3.52????

No, you do NOT have a Mitsubishi TD04 in youre 08 unless you did some kind of a swap to a 06 WRX setup.

Do more homework, or if this is a Troll thread..... try harder next time
The 08 is the bastard year wrx. It has a TD04-19t rather than the normal TD04-13t and has the compressor cover designed for LGT fitment.

Never heard of the stage 2.52 stuff before though.
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Old 12-05-2012, 09:28 AM   #8
xluben
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Quote:
Originally Posted by UK-Wagon View Post
Do smell I a Troll thread?

stage 2.52 and stage 3.52????

No, you do NOT have a Mitsubishi TD04 in youre 08 unless you did some kind of a swap to a 06 WRX setup.

Do more homework, or if this is a Troll thread..... try harder next time
You definitely don't know what you're talking about.

Quote:
Originally Posted by mechatricity View Post
I had to google it. Stage 2.52 is a Torqued Performance map for a VF52 on an 08 WRX.

OP: don't ask US what you need for SOMEONE ELSES map. Ask Torqued Performance.
Correct, these are TP map designations.

To the OP:

Once you swap the turbo, you're basically at the "Stage 2" level for all the 09+ WRX's. Many, many people run this setup with stock injectors and fuel pump. The fuel system will be the ultimate limiter to your power, but it's not "unsafe" to run with the stock injectors and pump as long as the tune is designed around these limitations.

If you want more headroom and don't plan to upgrade any more in the future, then you can do very slight fueling upgrades for peace of mind. 650's or 750's would be plenty of injector and any aftermarket pump would be fine (Walbro 255 is cheapest, DW 65c is a drop in).
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Old 12-05-2012, 04:26 PM   #9
ringlander
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What is a troll thread?
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Old 12-05-2012, 05:51 PM   #10
bhinak
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Quote:
Originally Posted by ringlander View Post
What is a troll thread?
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Old 12-05-2012, 06:10 PM   #11
ringlander
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So helpful
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Old 12-05-2012, 07:43 PM   #12
bhinak
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Old 12-05-2012, 07:53 PM   #13
424wrx
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im running the 3.52 map. its made for a 08 wrx with a vf52 swap,stage 2 mods and ebcs installed.the 2.52 is just a vf52 swap with stage 2 mods.the maps are from eric at torquedperformance.com op, check wrxforum.com eric is a regular on that forum.
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Old 04-01-2013, 07:01 AM   #14
'08WRXRider
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Thanks guys. Just looking for some peace of mind while making as much power as reliably as I can with the above mentioned mods.

BTW, Not a troll thread (whatever that is).
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