Who here owns a Subaru?

Soldato
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Thanks for that @Meridian.

I am on the side of keeping the TMIC for now. Would save me money and i really do dislike the look of the pipes going through the engine bay along with having to get rid of the Forge BOV and K&N panel filter.

Any recommendations on what Injectors to look out for? Going to go 2nd hand with these and get them sent off to be professionally cleaned. Seems a lot cheaper than buying new.
 
Man of Honour
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Would save me money and i really do dislike the look of the pipes going through the engine bay along with having to get rid of the Forge BOV and K&N panel filter.

sti_fmic_baypiping.jpg


sti_fmic_front_all.jpg


As for injectors, mine are Bosch 650s. In theory 550s will get you 400bhp, but if you are upgrading anyway then you might as well get some headroom. Just one thing to be wary of: when I had a 255 fuel pump fitted I got terrific fuel surge if I was turning right (like angling out of a roundabout) and the tank was less than half full. The intake is in the front left corner and the G forces pulls the fuel away from it. Leave this for now, but be on the lookout.
 
Soldato
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@Meridian

Nice install that actually. Though i still prefer the cleaner look of the TMIC.

Thats strange as it is exactly the same fitting as the pump i pulled out. Couldn't tell you what brand the old one was as the markings had been purposely scraped off for some reason, guessing it came with the PPP package though.

I had in my head bigger injectors will give me a bit more power over the pinks and be a lot less stressed. Basically get me closer to that 400 mark over the pinks. What do you think?

Basically i want to get the most out of the new turbo that i can. After the remap i will not be doing anything more power wise to the car.
 
Man of Honour
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You'll only get more power with bigger injectors if you're running out of fuel flow.

Stock 550s are good for 360bhp
650cc around 420bhp
750cc around 485bhp

I wouldn't recommend buying second hand, by the time you've messed about buying second hand and having them cleaned flow tested you won't be far off the cost of new
 
Man of Honour
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ok. so you can you just get 1000cc injectors and run 400hp? or do you have to run really big power with big injectors??
Outright power isn't the issue with big injectors, it's the low pulse width stuff (Idle and cruise)

ID1000s (1000cc Injector dynamics) will actually idle a stock 1.6 MX5 better than stock 240cc injectors
 
Associate
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I used 750cc injectors on mine.
The only reason I went up in injector size was because the car was starting to lean out due to injectors flowing their max.

I made 410bhp but was way too lean. Backed off a little for a very comfortable 396 iirc.
All at 1.5 bar boost.

What really helped me flow extra power was the addition of the RCM headers wrapped with the venturi up pipe.

Bigger injectors are important but imo not needed at this point of tune. The 550s will flow enough fuel for you to produce good numbers.
 
Soldato
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Bigger injectors are important but imo not needed at this point of tune. The 550s will flow enough fuel for you to produce good numbers.

Seems to be mixed opinions on this which just made me think bugger it, i may aswell get some. Got a few like Frozenova saying they are only good for 360-380 max and others saying they have seen 400+ out of them.

Are they just as reliable at 90%+ capacity as they are at say 80%? No chance of starving the engine?

Thanks
 
Soldato
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Not to mention the obvious issue that you need to ask: "why are they being sold?" The most likely reason being that they aren't up to scratch.

I have only been looking a full cars being broken at MBDevelopments, Scoobynet etc. Found some ZEN Performance 750cc injectors for £120 and was planning on getting these and get them professionally cleaned at £56.

Not so good of a idea?
 
Man of Honour
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Seems to be mixed opinions on this which just made me think bugger it, i may aswell get some. Got a few like Frozenova saying they are only good for 360-380 max and others saying they have seen 400+ out of them.

Are they just as reliable at 90%+ capacity as they are at say 80%? No chance of starving the engine?

Thanks

All my numbers above were based on stock 3 bar fuel pressure.

Bump the fuel pressure to 4 bar with an adjustable FPR and they effectively become 650cc, which is the easiest option if you don't plan on going over 400bhp

Edit: FPR is exactly how scoobydoo69 got 400 out of his stock 550s
 
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Man of Honour
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I have only been looking a full cars being broken at MBDevelopments, Scoobynet etc. Found some ZEN Performance 750cc injectors for £120 and was planning on getting these and get them professionally cleaned at £56.

Not so good of a idea?


If you know the history, then you may be OK - I'm just being paranoid. My injectors were done by Zen, so the 750s are probably Bosch as well. But with 750s, even if they aren't perfect you should be OK as they are way more than you actually need.
 
Associate
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When Duncan mapped mine throughout the entire history of my subaru I never used a FPR.
I used a 3 port boost solenoid.

The only real mods I had on mine were:

Cobra 3 inch straight through pipe.
RCM headers wrapped with venturi up pipe
GGR group A filter ( just a bit bigger than the RCM cone filter )
SC38 Blouch turbo, mated to a mishimoto silicon induction hose.
42mm core aluminium racing radiator.
750cc injectors top feed( bought off ebay for £185 )
20% methanol map. Running 1.5 bar boost.
Exedy pink racing clutch.
Tein S sport springs x 4
KYB Ultra SR shocks x 4
Whiteline droplinks.
Whiteline 22mm ARB rear
Nankang NS2R 225 40 18 (120)
Team dynamics PRO 1.2

Made 436bhp 385 torque @ SRR August 2016
Countless 12.1 1/4 mile runs
Fastest was 12.13 @ 113 mph twice lol

Exact specifications. It was simple plus quite cheap, however very effective. Biggest purchase being the turbo. It worked for me, without going heavy into FPRs etc
 
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Soldato
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Nice one thanks for that @ReAPeR101

ATM i have:
Straight through 3" exhaust
SC38
255 fuel pump
uprated the spark plugs as recommended by DG
K&N panel filter
3port boost solenoid

The uppipe was aftermarket but im not sure what one it was. I should have had a proper look really, saying that though my mechanic did it on my driveway from the top of the engine bay and didn't have to remove anything else other than the intercooler. SC quoted me 4 hours to do it in there workshop, my mechanic did it in just over 2 hours on my driveway lol. :rolleyes:

What would you say the headers was worth power wise? Also do you know the figures without the meth?

Thanks

EDIT: ignore that last bit, you have already explained it in the previous posts, having a re-read now.
 
Associate
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Nice one thanks for that @ReAPeR101

ATM i have:
Straight through 3" exhaust
SC38
255 fuel pump
uprated the spark plugs as recommended by DG
K&N panel filter
3port boost solenoid

The uppipe was aftermarket but im not sure what one it was. I should have had a proper look really, saying that though my mechanic did it on my driveway from the top of the engine bay and didn't have to remove anything else other than the intercooler. SC quoted me 4 hours to do it in there workshop, my mechanic did it in just over 2 hours on my driveway lol. :rolleyes:

What would you say the headers was worth power wise? Also do you know the figures without the meth?

Thanks

EDIT: ignore that last bit, you have already explained it in the previous posts, having a re-read now.

Post 3220 i think LOL

But just to recap for you. Mapped with 1.5 boost.

328bhp 330lb Cobra 3" exhaust, K&N Panel filter, Remap, Racing rad, (only reason for the rad was because the original had a leak, thought i may aswell upgrade)
371bhp 340lb SC38, Cobra 3" exhaust, K&N Panel filter, Remap, Racing rad.
395bhp 350lb RCM wrapped headers, Venturi up-pipe, GGR racing cone airfilter CAI, Mishimoto induction silicone hose, 3port boost solenoid SC38, Cobra 3" exhaust, K&N Panel filter, Remap, Racing rad.
413bhp 358lb 750cc injectors, RCM wrapped headers, Venturi up-pipe, GGR racing cone airfilter CAI, Mishimoto induction silicone hose, 3port boost solenoid SC38, Cobra 3" exhaust, K&N Panel filter, Remap, Racing rad.
436bhp 385lb 20% Methanol remap, 750cc injectors, RCM wrapped headers, Venturi up-pipe, GGR racing cone airfilter CAI, Mishimoto induction silicone hose, 3port boost solenoid SC38, Cobra 3" exhaust, K&N Panel filter, Remap, Racing rad.

Biggest jump in BHP was with the turbo being added, however i lost a bit of low down torque, which is what i expected as it is a 18g turbo, so bigger.

Adding the headers etc helped the turbo breathe far better, adding those parts, the torque returned. 1/4 mile times around this time were 12.6 - 13.0 secs with ET times around 103 - 108 mph

Adding the injectors, i gained a bit more boost towards the top end of the rev range, as the injectors were not leaning the engine out, still maintained low down torque 1/4 miles at this stage for me were 12.4 - 12.8 secs 103 108 mph

Adding 20% meth was the best bit LOL ( reminded me of the old days with nitros ) i gained between 20 / 30 bhp across the entire rev range. Depending how i launched the car etc 1/4 mile times were 12.1 - 12.5 113mph was my consistent trap speed

best regards
 
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