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Help please!!! Injector question + More


neilg

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Hi everyone

What are UK injectors good for running power wise?

What colour are they?

Will they go straight into the J-spec fuel rail?

Do i need a resistor pack or something? If i do where do i get one?

What colour are jap injectors?

How much should i expect to pay for a set of UK injectors? (new/used)

 

Im wanting to remove the 1st cat and run with no restrictor ring.

 

Will i be safe?

 

I currently have

93 j-spec TT

2nd cat gone

HKS Titanium

blitz sus

mines ECU

 

Planning on getting

spark plugs

maybe a FSE

Walbro

UK Injectors

 

Is there anything else i need to know?

Anything else i need to get?

Do i need all the above or can i do away with any of it?

Im i right in thinking that removing both cats will give me around 1.2 bar?

 

Help appriciated guys and gals :thumbs:

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What are UK injectors good for running power wise?
min 450 - max 500bhp

 

What colour are they?
UK 550cc - Lilac/Purple

JDM 440cc - Grey

 

Will they go straight into the J-spec fuel rail?
Nope, you'll need a UK spec fuel rail or an aftermarket one.

 

Do i need a resistor pack
Yes

 

If i do where do i get one?
From Emin (SupraTTMyster) or Toyota

 

What colour are jap injectors?
See above

 

How much should i expect to pay for a set of UK injectors? (new/used)
£100 - £200 used.

New? Dunno

 

Im wanting to remove the 1st cat and run with no restrictor ring.

Will i be safe?

No, You'll boost too high without a restrictor.

 

I currently have

93 j-spec TT

2nd cat gone

HKS Titanium

blitz sus

mines ECU

 

Planning on getting

spark plugs

maybe a FSE

Walbro

UK Injectors

 

Is there anything else i need to know?

Anything else i need to get?

Do i need all the above or can i do away with any of it?

Get on a dyno and have your fuelling checked ASAFP after the upgrades. You might not need a FSE as it's only good for richening the AFR.

 

Im i right in thinking that removing both cats will give me around 1.2 bar?
and then some!
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Right am i right in thinking -

 

jap injectors- 430cc high impendance

UK/US 550cc low impendance

 

Does that mean if i can get some 550cc high impendance injectors i can avoid using resistors????

 

Or am i talking rubbish??

 

Still need help on anything else i was blabbering about :stupid:

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this subject is pretty much done to death if you do a search, but heres my limited knowledge

power 550 cc injectors=roughly 550 hp

colour of uk injectors= light purple mauve sought of

fuel rail= will go straight in j spec

resistor pack = yes, someone on the site used to do them, or contact the traders

injector price= £150-£200 when they come up, or contact the traders

one cat in will not need a restrictor ring

a walbro and a fse certainly wont do any harm

does the mines remove fuel cut ? if not you will need to sought that

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Hi everyone

What are UK injectors good for running power wise?

What colour are they?

Will they go straight into the J-spec fuel rail?

Do i need a resistor pack or something? If i do where do i get one?

What colour are jap injectors?

How much should i expect to pay for a set of UK injectors? (new/used)

 

Im wanting to remove the 1st cat and run with no restrictor ring.

 

Will i be safe?

 

I currently have

93 j-spec TT

2nd cat gone

HKS Titanium

blitz sus

mines ECU

 

Planning on getting

spark plugs

maybe a FSE

Walbro

UK Injectors

 

Is there anything else i need to know?

Anything else i need to get?

Do i need all the above or can i do away with any of it?

Im i right in thinking that removing both cats will give me around 1.2 bar?

 

Help appriciated guys and gals :thumbs:

 

Will try to answer some of your questions before some of the more tech guys arrive:

 

- The 'old' rule is that 550cc injectors are good for 550bhp (440cc for 440bhp. 650cc for 650bhp, etc), though this will be pushing them to the max if your achieve any way near these figures.

- You will need a resistor pack if you are to use UK injectors but will also need something to control the fuelling (e-manage, AEM, etc).

- UK injectors (550cc) have a lilac cap, jap (440cc) have a grey cap

- Not sure how much you would pay (guess at £200) but if you are going to do it properly you may as well go for some low impedance injectors from somewhere like vortex. It will save cutting the loom!

- Running full decat without a restrictor ring on a jap car will mean massive boost (1.4bar + is likely), regardless of what else you have done, you will severely shorten the life of your turbo’s.

- From personal experience, if you are going to a full decat, make certain you get the following FIRST:

* Walbro fuel pump

* Good NGK or Denso iridium plugs

* New fuel filter

* decent engine oil (i.e Silkolene Pro-S, not a thin oil like mobile1)

 

As uprated injectors will require a big investment in money and dyno time I would only bother with them after all basic mods have been made. An uprated intercooler would probably be a better upgrade before fuelling and engine management.

 

HTH

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Thanks Paul,

I believe the ECU does remove fuel cut.

 

I know this topic has been drained to death, you know what its like though, every one says different and you end up going mad.

 

Just the same as you have just said the injectors will go in a std jap fuel rail but Jake said i need to get a uk one?????

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min 450 - max 500bhp

 

UK 550cc - Lilac/Purple

JDM 440cc - Grey

 

Nope, you'll need a UK spec fuel rail or an aftermarket one.

 

 

Sorry Jake But the UK and J-spec rail are one and the same so it will not need any mods for putting in the Uk injectors! .....Thats saves you some pennies ;)

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Cheers everyone,

 

Getting somewhere and starting to undestand a bit more now. Deffo have to get a restrictor ring in then, ill be ok (ish) at around 1.2 bar i take it????

 

In theory then i could avoid changing the injectors for the min???? Will my jap ones take both cats out ok???? If i do the fuel pump??

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Sorry Jake But the UK and J-spec rail are one and the same so it will not need any mods for putting in the Uk injectors! .....Thats saves you some pennies ;)

phew thanks for that mig, bought a set of 550's of CJ a while back who told me they drop straight in, panic set in for a minute there, sorry neil miss read your original post you will defo need restrictor mine is hitting 1.25 with one in at the mo with the cold weather

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If you change the injectors you need to have something to control them. What with the cost of the injectors, rail (okay thats optional), fuel controller, mapping and dyno runs - From what I have worked out so far its almost as expensive as having a budget big single turbo fitted.

 

I'd go for all the supporting mods first, then think about injectors. My car seems to be running quite okay with just the mods in my sig (though FMIC and new FPR are going in soon, just to make sure ;) )

 

edited for bad spelling :looney:

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Most people double-decat and put in a restrictor ring and run like that at around 1.2bar of boost. Your 440cc injectors will be flat out though and your fuelling will be on the edge at some points in the rev range.

 

Bigger injectors like the UK spec are the way to go if you are serious about sorting your fuelling out. UK spec 550's will drop straight into the J-spec fuel rail, provide enough fuel for stock turbos at 1.2bar, and any boost beyond that won't give you more power and can affect turbo lifespan. If you go for bigger injectors, you won't need an FSE, that's a nasty fudge to push inadequate injectors a bit further. You will need a resistor pack though as the UK's are *low* impedance, meaning they need additional resistance. If you don't want to fit a resistor pack then you need *high* impedance injectors, and Vortex Power do some 650cc ones that drop straight into the stock fuel rail.

 

You'll need that Walbro pump to feed them, and at the end of it all you'll need some mechanism for trimming the fuelling back until you need it - at this level an Apexi AFC is good enough for the job but for £notmuchmore you can get an E-manage which is a way better tool. Getting 650's and an E-Manage future proofs a lot of your fuel system for any further upgrades in the future.

 

Fitting bigger injectors, maybe a resistor pack, and an airflow controller to sort the fuelling out is not near the cost of a budget single turbo install, I'd say...

 

Oh, and UKs are lilac, J-specs are grey, as everyone else has said :)

 

Argh, I've just noticed that you've got a MINES ECU. That's a law unto itself, Matt Harwood has had lots of trouble trying to airflow map one of those. Personally I'd swap it for a stock ECU as trying to trim the fuelling down on one of those is a nightmare.

 

-Ian

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I would fit the 1st cat and restrictor ring and get onto a dyno. My experience has shown that the Mines ecu runs pretty rich. You'll probably find that even at 1.3bar you're safe on the fuelling. Must put it on a dyno though to be sure. Never assume it'll be ok. I'd leave the fpr until afteryou've been on the dyno/r.road I very much doubt it'll be needed, the Walbro may not be 100% necessary but you won't do any harm fitting it and it gives peace of mind.

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Right then.

 

I think ill remove the first cat, put in a restrictor ring. change to a walbro. Change the spark plugs (needed anyway) Take it for tuning and see whats its upto. Then as you have all said i will know where to go from there.

 

Do i get IK24`s to support what i want?

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