At what power level should you change to parallel fuel rails?
 

And do they need different injectors? Side feed? Top feed? I haven't a clue but I'd like to know more....

normally you'll buy the rails that suit your car - some models are sidefeed (classics/JDM foresters) and some are top feeds (newage wrx/sti etc.) so look at what you have and get the right kit.

the fuel regulator will have to change as well, you can often buy a complete kit for installation (fuel rails, regulator, hoses etc.) so that will make things a lot easier.

as for when to upgrade to them, your stock fuel setup should have no problems holding up to 400hp - when your considering giant size turbos then it's a good time to fit rails and larger injectors together as part of a complete set of upgrades.

'Parallel' rails or set up is a good idea regardless off power to equal the distribution of fuel to each cylinder for longevity of engine, rarther than a 1,2,3,4 order which means the number 4 get fuel last hence can damage that cylinder in long run

Yeah I wondered about that.

It's a Blob STI (widetrack) and I believe that's side feed?

widetrack blob should be 550cc top feeds as standard.

Ah OK cheers. Good info. All I know is they're pink lol.

If you want a good budget rails without paying mad rcm tax etc and better than the leaky cdf range then look at JAWerehouse rails

Are the CDF ones no good?

I personally don't know to confirm, but there is a LOT of complaints about them on here over time.

Its actually 4-2-1-3 with the fuel pressure regulator on the end of the line feeding out from cyl 3 at least on classics, cyl 3 is the one that can possibly run lean due to lack of pressure after passing 3 injectors in series before reaching the fourth, I am pretty happy with how the JA Warehouse ones turned out.

http://imgur.com/a/oPZsf
http://imgur.com/a/7s1rQ

If these fuel rails from JAWarehouse are ok then I'm tempted to get some,I've been wanting to do a conversion for a while now and these are a very good price!

I'm looking at getting this kit in the link> http://www.ebay.co.uk/itm/Impreza-WR...AAAOSw7FRWUtDw

I have a FPR I bought ages ago,apart from a fuel rail adaptor is there anything else I would need to complete the conversion?
Also is it best to take off the inlet manifold to fit or is it easy enough with it in place?

You will have to take the manifold off as the std fuel rails are bolted to the manifold in several places underneath, you will need around 2-3m of an-6 hose and various an-6 fittings i ended up using 6x an-6 90° elbows 3x an-6 straight 1x an-6 45° an an-6 t-piece to split the supply to two rails in parallel and used a fuel pressure regulator with 2 input ports and one output to the return

I would not bother with the kit the 1/2m of hose and small section of hard pipe are useless you can just buy the JAW rails and mounting kit with thread adapters then buy hose and fittings separate, although you will need access to a vice and soft jaws to make up the an-6 hoses yourself.

Nice one cheers.
Would you know if anywhere does the pipework made up to suit so I could just plug&play? Just feeling a little lasy atm lol

Sorry no idea on who could make up the hoses for you i took mine to work and did them in between machine breakdowns jobs etc.

Cool thanks for the advice on pipe&connectors.
Is a good idea of yours,I think I'll make mine up at work,I get some decent runs on so loads of time to kill :)

Like the look of the JAWarehouse kits. Looks like the same gear as the Kinugawa ones.

There's this full kit:
http://www.ebay.co.uk/itm/361961901552

But I'm not sure if it's as good using the hard pipes included with this kit rather than normal braided hose? Same with the supplied FPR, I think I'd rather spend the money and get a Fuelab or RCM FPR to use.

I'm going to have the manifold off to fit the inlet hose I've got and will be buying some spacers from Alyn. Looks like I should also do the rails at the same time.

No, I wouldn't buy the kit with hoses etc, just buy the rail kit only and buy good quality hoses from likes of torques etc.
I made the mistake of buying the kit and the hoses are crap quality and a pita to get the AN fittings over them.
The jaw rails have got good reviews for price, hence I bought them, just be careful you get correct washers as they sent too thick ones on another car Tim was doing, but mine was fine.

final 45° fitting arrived last night so I finished the piping up this morning to show the layout

http://imgur.com/a/5Tv8j
http://imgur.com/a/iYgGJ
http://imgur.com/a/OK9Qq

The T fitting under the manifold in third pic is supply from fuel filter, the bottom of reg 90° goes to return you can just use jubilee an-6 hose finishers straight onto the plastic hard pipe return to tank and pipe the T piece straight to fuel filter (supply) in stainless hose also with a jubilee end finisher.

Do not buy the 12.5mm finishers they are too small I made this mistake and ended up having to order the 15mm ones

The evaporation lines + valve etc are all deleted in this setup, hose is just plugged or left to vent with some kind of breather filter if you don't like the sound of tank sucking in air whenever you fill up

I would also advise using at least 13mm if not 15mm or greater thermal spacers for anyone attempting this or you will struggle to find clearance for hoses.

Just using a cheap reg for now for £40 from ebay to prove the design has no issues and keeping costs down as I have a lot of more important parts to replace, once its ran for a bit without leaks I will swap the regulator for a perrin or RCM one.

who also offers FPR's, rail kits, etc............;)

I'd only buy from AS after having a couple of lines burst from other suppliers. The lines AS sell are the best and I'd also recommend using the thermal sheath they sell for any really hot areas like aver the turbo.