550cc injectors

[dave barratt]

Do u have to have a separate controler if u swap over j-spec 440's to uk 550's or will engine still run ok? i no u need a resitor pack if u ue standard uk spec's

[Nic]

Do u have to have a separate controler if u swap over j-spec 440's to uk 550's or will engine still run ok? i no u need a resitor pack if u ue standard uk spec's

 

You will need something to control the fueling, otherwise you will run very rich. Apexi SAFC is the minimum you'll need, personally I would go for the emanage or emanage ultimate at least, so you can also map the ignition.

 

Give me a shout Dave if you need prices for any of the above.

[dave barratt]

Thanks for the advice Nic.

You will need something to control the fueling, otherwise you will run very rich. Apexi SAFC is the minimum you'll need, personally I would go for the emanage or emanage ultimate at least, so you can also map the ignition.

 

Give me a shout Dave if you need prices for any of the above.

[Ian C]

You'd need to plumb in a resistor pack for the injectors as well, dunno if you'd taken this into account or not.

 

-Ian

[Nic]

I priced up a set of brand new 550cc UK spec Supra injectors yesterday and they're suprisingly cheap compared to after market alternatives. So if anyone else is wanting to upgrade to 550cc injectors, let me know and I'll send you details.

 

If there are a few who want them, perhaps I can organise a group buy.

[Guest Bijal]

i personaly dont see any point in wasting money on new 550cc injectors.

 

If you are getting them REALLY cheap then its fine.

 

But you'ed be better off buying slightly larger injectors so that your future proof in case you decide to go bigger turbos or single etc!!!!

 

the cost difference wouldnt be that much.

 

plus with the Apexi SAFC2 or Emanage you have plenty of control over the injectors anyway, so that wouldnt be a problem there.

 

worth thinking about it

 

Bijal

[Nic]

I don't personally agree, it is always best to fit the correct sized injectors to suit the application.

 

If you are running stock turbos or hybrids then 550cc is what you want, yes *if* you go single in the future you'll be needing bigger, but you'd easily sell on the 550cc injectors when you do and be able to upgrade.

 

Speccing parts on your car for some possible future tuning need, that you may or may not carry out, is not the way I would personally do it.

[Guest Bijal]

The 550cc will max out with hybrids, depending on how much boost the hybrids can create. and these days less people by hybrids as single kits work out the same or cheaper!!!

 

also, the stock 440cc injectors on J Spec Supras can cope enough up to 400bhp safely. and by adding 550cc injectors, uk resistor pack and a fuel controler you cannot up the boost anyway as your stock J spec turbos will start running out of steam at around 420bhp, and the stock 440cc injectors can cope up to that.

 

bijal

[Ian C]

You can run 1.2bar boost on stock turbos on 440cc injectors, I wouldn't like to say it was 400bhp though, all I know is airflow and duty cycles

 

I've been mapping a set of phat hybrids on 550's and at 1.2bar 6500rpm we are seeing 80% duty for 11.8:1 afrs. These hybrids will run up to 1.4bar before power markedly drops off, so the 550's will merrily fuel for that, but not a lot further.

 

650cc injectors will run stock turbo setups, but you will find it easier if you wind the fuel pressure down a few psi. Even then you're using 60 to 70% duty tops. Any larger than that is futile. The low impedance 650's are a good bet as a) they drop right in with no respack, b) they aren't too expensive, and c) they will fuel anything from stock turbos without cams to a T61 at 1.4bar.

 

-Ian

[Jake]

low impedance 650's are a good bet as a) they drop right in with no respack,

I think you mean High Impedance. Low Imp would need a resistor park.

[Guest Bijal]

You can run 1.2bar boost on stock turbos on 440cc injectors, I wouldn't like to say it was 400bhp though, all I know is airflow and duty cycles

 

I've been mapping a set of phat hybrids on 550's and at 1.2bar 6500rpm we are seeing 80% duty for 11.8:1 afrs. These hybrids will run up to 1.4bar before power markedly drops off, so the 550's will merrily fuel for that, but not a lot further.

 

650cc injectors will run stock turbo setups, but you will find it easier if you wind the fuel pressure down a few psi. Even then you're using 60 to 70% duty tops. Any larger than that is futile. The low impedance 650's are a good bet as a) they drop right in with no respack, b) they aren't too expensive, and c) they will fuel anything from stock turbos without cams to a T61 at 1.4bar.

 

-Ian

 

Last time i setup a stock J Spec supra 6 speed with 440cc stock injectors with the SAFC2, 3 Row Front mount, down pipe exhaust, plugs, we pulled 426bhp at the fly. that was at 1.3bar of boost, and to be honest, there was no need for the SAFC2 to be plummed in. The stock ECU coped very well, but yes, injectors were maxed out. There for i said 400bhp would be safe, obviously provided you have front mount or something to cool the charge temp.

 

good comparisons though, very useful to peeps.

 

bijal