Sounds good guys,

Cant wait to get my blow through setup done. Looking forward to seeing the results once you turn the wick up Neil

Seriously looking forward to seeing the results ... but sounds very promising so far

Been following quiet a few of these projects for a while now, very inspiring and there should be a lot of proud people out there.

Rolling Road today is it not? C'mon don't keep us waiting too long on the dyno results :-)

isnt these rails nicer? fuel_rail_sti.jpg | Album.ee

Indeed those rails you show are nicer, however I suspect that they would cost more than my whole fuel system put together...

Not been on a rolling road as yet, however having had some more mapping carried out, and the rough figures so far are 430horses, and 460 torques.

Slightly down on the outright power I expected, but torque seems about right, and extremely good to drive as a result...

if you say how much you fuel system cost then i can tell is that so or not

but this small thing don't change this create project. paint and renew every detail this is

you'll find him on ebay and they are £99...... not sure if i would trust it though

heres the latest sale.... Subaru Impreza Fuel Rail kit on eBay, also Injection Fuel Systems, Performance Tuning Parts, Car Tuning Styling, Cars, Parts Vehicles (end time 10-Sep-08 18:25:20 BST)

if rails and fittings were quality..... well?

that looks well cheap if it turned out to be anygood

looking nice mate i would love build my own scooby !

Fantastic Car mate and a really good read. There is nothing I would change on the car at all and you have create something that is truely top notch.

Just noticed Andrew C from Preston is doing your mapping.

Spoke to him last night about looking at my wrx when I get it back....TOP BLOKE.

Loving your car, what a read - well worth it, great effort!

keep going fella and dont sell it for silly money

Quick update..

Having done enough miles on the car for running in, it was time for 'final' mapping, which was done by my usual mapper chappie..

This was done on a stretch of dual carriageway which was, erm, a bit wet to say the least with plenty of standing water about..
Having mapped my previous classic with a similar engine spec, I was somewhat concearned..

Anyway, off we trots to do the do, no problems and no drama's..

Now initialy I wasn't overly impressed, but put that down to the fact that I was comparing the performance to my old classic which was probably about 250kg lighter than this car. (maybe more due to excessive soundproofing that I have fitted to this car)

No worries, as the intention of this car was to be a bit smoother, quieter and easy to live with than the classic, which was always a bit raw.
This car hopefully will take me around Europe next year, with a few trips to the Ring and down the Stelvio pass, and hence has full creature comforts..

Anyway, after speaking to AndrewC (mapper) he mentioned that the engine doesn't seem to be very efficient towards the top end, and driving the car seems to suggests just that.
Andrew seemed to think that it may be the rear silencer on the car.

As posted earlier in the thread my system is 3" to the rear box, where I then reduced it to 2.5" via a Prodrive back box, which I did intially for both sound and looks.

So, off with the rear `silencer, and I put my 3" section on it as a temporary measure to see if any difference was made.
Now, straight away the car sounded better, of course , and felt a bit crisper, but I wasn't too sure if that was the new sound of the car decieving me somewhat.

A quick trip to Andrews, and mapping gear attached, quickly confirmed that the rear exhaust had indeed made a difference, with it leaning out towards the top end, due to better efficiency of the new set up, which he soon amended.

Now the car is getting near what I REALLY wanted, although it is probably a bit too loud for my age..

Sounds good

Looking forward to seeing it in a few weeks on the rollers at Zen.

OK, since getting the car on the road, there are numerous things which I wasn't 100% happy with, and as and when funds/time permit, I am tackling them one by one.

Firstly, my downpipe..

The one I originally fitted was a twin pipe jobbie.
From what I can gather it was a custom made part for a friend of mine, and I ended up with it as part of some deal.

The idea I guess was for the 2 pipes to take care of the exhaust gases and the wastegate gases separately. However once I looked at how the wastegate actually operates, the idea seems flawed.

Anyhow, off with the downpipe, and out with the hacksaw to creat a new open mouth downpipe.

Old (albeit somewhat chopped) vs new...



New wrapped item.




Another area was my induction system.

Initially I had 3" pipework created using ducting, along with a mickey mouse air filter, which I thought would be OK for running in purposes, and 400ish BHP.

I've now replaced this with a 260mm K&N item, along with a spun alloy trumpet.
This is connected to the turbo now with 90mm ducting, which is the largest I could get under my inlet manifold.
I can now literally get my whole arm inside the pipework and touch the turbo.





The plan ultimately is to make some kind of mould of this whilst in place and have a silicone version produced at some stage.

I have recently had the car on a rolling road day along with my local Subaru club at Prosport, which yielded these figures..(apologies for the crap graph. )



426 bhp, 481 lb/ft.

Not especially high power figures, but great torque, which does translate to how the car performs on the road.

However, the car was mapped before the above mods were made and as such I suspect(hope) there is more to come.

Having said that, I have still comfortably met my target of 400+...

What a great torque figure power ain't bad either

Glad your still keeping updated on this great project

Performance not to be sniffed at by any means mate.

I think people get wrapped up in power figures and unless its 500+ its no longer a fast nor impressive car. I dont care what anyone says. Any Subaru, or indeed any car with over 400bhp on tap is going to be seriously quick on the road.
Thats an awesome torque figure too Neil, what boost was that running?

Congrats anyway mate on still one of my favorite projects to date.

Cheers chaps.

Boost peaks at 1.85ish, and tails off to 1.6/1.7 ish according to my Defi's.

Same results i saw with a T

Expels the myth of a 321T making 450bhp at 1.5bar.

Dont worry chap im not knocking it one bit. Its just nice to see some real results for a change.

Well done

Hence one of the reasons I suggested the forthcoming rolling road day at Zen.

Neil's last car made 450/450 on the same rollers at 1.5bar IIRC.

Will be interesting to see what it does on Dastek

Indeed it did Andrew, however it also made 'only' 428 BHP 6 months later on the same rollers...

Looking forward to the Dastek run, alongside some of the big power lads..

just catching up on the car. awesome job see you soon as i might by near yours so i will pop in cheers mick

How did you get on at Zens rollers Neil?

When is the rolling road day at zen gents??

Sunday just gone

22B Bulletin Board: 2.5 rolling road day

Sorry chaps, not looked for a few days..

Anyway, quick update..

Along with the power run shown above, I also took part in the above mentioned rolling road day at ZenPerformance last Sunday, initially for owners of other 2.5 engined Impreza's.

Bearing in mind that not a lot had change motor wise, the figures came out slightly different..



440 bhp, 458 lb/ft.


Another small change is the Maf/Intercooler pipework...

From this, with a step down and an awkward joint.....





To this, all one size, and less joints to pop off at boost..





Next step is to get her nicely over the 450bhp threshold, whilst using less boost...

thats really nice; smooth clean curves...its got to have increased air flow

An absolutely fantastic motorcar.