Port injection- what injectors to use!?

[Builtfc1]

I am picking up a built transmission next month and now I’m already planning on going full send with my car. Already have everything done possible and now want to get into port injection/Motec. That being said what size injectors are the go to and what brand I’ve seen one guy use ID 1050’s. I can only find them for fk8’s, does it matter once on a standalone ecu?

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[speedyserg]

Injectors don't car what the car is - the smaller the injectors the easier it is to fine tune.

Port injection is touchy as most guys remove the tumble from the head when they port it so you have to ve careful not to over fuel the car or you'll end up washing the rings out and get cyl wear/scratches quickly.

Start small - small is cheap
You can upgrade the DI injectors and use the PI to supplement fuel.

John P uses PI to provide a ton of fuel and cooling using the port injection for direct methanol injection - like 60% of his fuel is the PI meth and 40% is the DI injection. Methanol is cheap and an excellent way to keep the motor cool while being aggressive with the ignition timing.

With a ported head you can easily run 28-32* of ignition timing with meth on FK8s..... stock head is iffy past 21-22*

What cams/head port are you going to run....power goals?

 

[Boosted_01_R]

I am picking up a built transmission next month and now I’m already planning on going full send with my car. Already have everything done possible and now want to get into port injection/Motec. That being said what size injectors are the go to and what brand I’ve seen one guy use ID 1050’s. I can only find them for fk8’s, does it matter once on a standalone ecu?

I would go with the new gen X series ID, 1300X or 1700X. What power/fuel are you targeting ? Check out the calculator on ID's site, around 80% is a good duty to stay around. Any tuner that is worried about big injectors, get a new tuner. My ITR was on old school Precision 1000cc injectors, started and ran like stock. I have since moved to 1100cc Bosch EV14's poor man ID's lol. Motec will have zero issue with it. Hell if you went with 2000cc it will be fine...
I would ditch the DI completely, plug the head.

Picked up a Skunk 2 manifold recently for the L15, you can get a fuel rail from S2 and run port injection that way, but check injector height. My eventual goal is to ditch the DI as well, but waiting for a more cost effective setup from Haltech one day, as I will share my Haltech R3 with the Si as well if some support comes to it....

 

[Builtfc1]

Injectors don't car what the car is - the smaller the injectors the easier it is to fine tune.

Port injection is touchy as most guys remove the tumble from the head when they port it so you have to ve careful not to over fuel the car or you'll end up washing the rings out and get cyl wear/scratches quickly.

Start small - small is cheap
You can upgrade the DI injectors and use the PI to supplement fuel.

John P uses PI to provide a ton of fuel and cooling using the port injection for direct methanol injection - like 60% of his fuel is the PI meth and 40% is the DI injection. Methanol is cheap and an excellent way to keep the motor cool while being aggressive with the ignition timing.

With a ported head you can easily run 28-32* of ignition timing with meth on FK8s..... stock head is iffy past 21-22*

What cams/head port are you going to run....power goals?

I have the hondata fuel system upgrade so what ever comes in that kit. Still on stock tb manifold and exhaust cam because it’s pointless to replace with aftermarket

 

[Builtfc1]

I would go with the new gen X series ID, 1300X or 1700X. What power/fuel are you targeting ? Check out the calculator on ID's site, around 80% is a good duty to stay around. Any tuner that is worried about big injectors, get a new tuner. My ITR was on old school Precision 1000cc injectors, started and ran like stock. I have since moved to 1100cc Bosch EV14's poor man ID's lol. Motec will have zero issue with it. Hell if you went with 2000cc it will be fine...
I would ditch the DI completely, plug the head.

Picked up a Skunk 2 manifold recently for the L15, you can get a fuel rail from S2 and run port injection that way, but check injector height. My eventual goal is to ditch the DI as well, but waiting for a more cost effective setup from Haltech one day, as I will share my Haltech R3 with the Si as well if some support comes to it.... If your on IG @75S30

Power goals not sure. It’s already making 430 on e60. But I can’t rev any higher than 7k because it’ll drop di fuel pressure above 7200. I’m out of fuel system. My gtx2867 turbo is good for 450-550

 

[Boosted_01_R]

Power goals not sure. It’s already making 430 on e60. But I can’t rev any higher than 7k because it’ll drop di fuel pressure above 7200. I’m out of fuel system. My gtx2867 turbo is good for 450-550

You won't need massive injectors. Spent a min on ID Calculator, go on and play around it's pretty simple

 

[Builtfc1]

You won't need massive injectors. Spent a min on ID Calculator, go on and play around it's pretty simple

Thanks man

 

[speedyserg]

I have the hondata fuel system upgrade so what ever comes in that kit. Still on stock tb manifold and exhaust cam because it’s pointless to replace with aftermarket

The smaller the supplemental injectors the finer the spray pattern and more accurate they are.

I'm on 2000cc and the 1450s have a better pattern but can't keep up with 8200rpm on direct injection for DI we keep duty cycle around 38% max and I'm around 32% on my 2000s at 600/490

If I had port injection I could go down to 1450s for DI and use some tiny 450s for the PI and supply quite a bit more flow.
My main concern with PI is after we port the head the fuel being sprayed can tend to gather up/pool - the finer the pattern the less chance of washing the rings out.

From the motors I've seen torn down on PI with ethanol they has some small scratches at 4000 miles. Not terrible but over time that could lead to alot of premature wear is all.

With regular injectors you can run them with a much higher duty cycle which is why they don't need to be all that large like the DI ones.

DI makes more power apples to apples but you run into fuel flow issues quickly. Port can solve that issue and also allow you to rev higher as it can supply the high rpm fuel the DI system can't.

Maybe talk to Ososik and see what setup he was running on the 700whp L15 he built a while back.

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