Sourcing 1200cc injectors

[elford_tim]

As I\'ll hopefully be playing with some uprated turbos on my FD fairly soon, I do need to look into uprating the fuel system as well. As my car still has the full emission control systems on it and is likely to stay that way (heck, I did pay for a new high-flow cat...) it looks like the direct replacement 1200cc injectors are the way to go.

My understanding is that RC Engineering in the US is just about the only source of these injectors, does anybody know if their standard 1200cc injectors are the correct replacements or if I have to jump through a few hoops to get some?

Sourcing in the US is not a problem, if I order them soon enough I can just get them sent to my wife and pick them up when I\'m over there in March...

[Mazdarotaryparts]

Morning Tim,

Whatever fueling system you go for please do not use 1200/1300cc injectors as many an FD engine has been lost in the U/K

Although we never experienced a failure we stopped selling these around 3 years ago  after some tuners and individuals were losing engines because of these.

They are bored out 850 injectors and apparently because of the thin walls once bored this can lead to them overheating sticking and an engine that runs lean and dies.

Hope this helps

[Ed_RX7]

Morning Tim,
 
Whatever fueling system you go for please do not use 1200/1300cc injectors as many an FD engine has been lost in the U/K
 
Although we never experienced a failure we stopped selling these around 3 years ago after some tuners and individuals were losing engines because of these.
 
They are bored out 850 injectors and apparently because of the thin walls once bored this can lead to them overheating sticking and an engine that runs lean and dies.
 
Hope this helps

Clive is right bud....I would STAY AWAY....not worth the risk!!!!

[nikp]

Mine died using 1200cc injectors......but i am not cinvinced that it was them that killed it.

[elford_tim]

Well, I had heard about the engine failures on cars equipped with these injectors, so I did have a long chat with my tuner of choice (RoTechniks) about my options, because I\'m a bit weird and don\'t want to junk the emissions gear unless I have to.

They suggest that they\'ve got several customers with these injectors and they haven\'t had any failures so far.

Of course if anybody has any suggestions as to getting a bigger pair (oooh errr) that fit the standard rail I\'m all ears...

[BlitzBoy]

if you are only going for uprated Twins, then go for uprated pump and 850cc injectors in the primary rail, more then enough juice

[Carl]

The reason that the 1200cc injectors fail is they get stuck shut at high fuel pressure which will happen as we use a rising rate fuel pressure regulator on turbo cars,for good reason just don\'t use them.
Regards
Carl

[elford_tim]

OK, so that\'ll be the 1200ccs out of the window then. How do 850cc primaries affect the \'mapability\' and the running? Are the OK on a PFC or would I end up with an engine that\'s overfuelling when it\'s running on the primaries only?

[Ed_RX7]

they are ok...i had that set up once....but didnt like the way it idled...and also couldn\'t get it lean enough at idle...........im very fuel concious!!....however they did work ok for me and do for many others both here and abroad........also its the cheapest method.......i have 660cc sard primary injectors arriving tomorrow.....but i have 1608 secondarys

[elford_tim]

Yep, I was afraid it would be something like "didn\'t like the way it idled" - IMHO the reason Mazda fitted the smaller injectors is to get decent control at small pulse widths, ie when idleing and pottering around.

I really didn\'t want to go the 1600cc route but that\'s beginning to look more likely. But first it looks like I\'ve got to sort out a few smaller problems...

[Ed_RX7]

yeh tim just go for the 1600\'s....will probably give you want yo want with plenty of room for improvement!!!...or should i say more horses!!

[shaunwil]

I had a similar problem and got told that the 1600\'s with a custom rail don\'t fit with all the rats nest under the plenum. Been using the 1200\'s for about 3yrs without issue. Although they where 2nd hand off WGT, had been in another car for alot of miles with no issues and had been cleaned and flow tested.

Looking at a single turbo very soon, hopefully fitting in the next couple of months. Not sure what I\'ll want to do on the fueling side where petrol is concerned. Looking at a completly different fueling system :Giggle

Can you not get better idling off the 850\'s by using a FJO injector driver and eliminating the resistor and opening lag ?

Shaun

[clive]

I had a similar problem and got told that the 1600\'s with a custom rail don\'t fit with all the rats nest under the plenum.
Shaun

It\'s tight but you can fit the 1600 rail with all the rats nest in place as I have carried this out on a couple of cars over the years, from memory, one was James Barrings car.

[hairyhoover]

Ive got a set of brand new 850cc injectors with flow print outs if your interested? Im not after much!

[nikp]

I have a set of 1200\'s looking for a new home. They weren\'t the source of the failure as i thought they weren\'t, but have gone the 1600cc route now.