Fuel Injector upgrade

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Swanny
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Fuel Injector upgrade

Post by Swanny »

I've had my XR4Ti sort of on the back burner for a while, I've Megasquirt'd it, chucked a big turbo on it, and take it out for what we call "Happy Laps" with a car club at my local raceway, which is a sensible speed around the curvey bits of the track, but when you get to the straight you can open up and get to "70mph" (1/8 mile) before getting sensible again.

At the same time, I'm replacing some rusty boot channels in my '71 Fairlane (it's like your Galaxy over there), and driving my Falcon XR6T ute as a daily.

I came across a wanted ad on our Aussie Ford Forums, that someone had bought a Falcon ute with an aftermarket exhaust, but he kept getting the MIL light come up on the dash, and then he had no boost. So he wanted to swap exhausts for a factory setup.

I put my hand up, and we did a driveway swap.

Image

I then (weeks later) got my car booked in to be dynotuned with an aftermarket system, dropped off the car, and got a phone call to say the fuel injectors were being max'd out. I agreed to pay up for some 1000cc injectors for $750 fitted.

At the end of the day my Falcon ute came out with 395hp. The changes made were a bigger exhaust (4" dump, high flow cat and 3.5" exhaust), a K&N high flow air filter and the injectors.

I got to thinking, what if I put the injectors from my Falcon into my XR4Ti? After all, the factory injectors were providing about 360hp. But... when I looked into it, my Falcon injectors are rated at 28lb, which is lower than the brown tops in the XR4Ti.

Enough of the background.... What pintle type injector is a good upgrade for the 2.3 donk? I've got my ute going fast enough it scares me, now I want the little red car to do the same (against all the V8 bogans I come across.

Apologies for the here, there everywhere post... I'm coming off a week of nightshift!
Red 1985 XR4Ti

Blue 2016 XR6T Falcon Ute

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merkurdriver
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Re: Fuel Injector upgrade

Post by merkurdriver »

Stepping up to 42 lb injectors is kind of the next step over the stock 36 lb brown tops.
A simple pigyback chip on the back of the stock ECU, pop the 42 lb ones in and go. Plug-and-play nearly.

However you already have megasquirt installed so the sky is the limit really.
( I've seen XRs with 96 lb injectors on megasquirt before which are the equivalent of the 1000cc you put on your other vehicle. )
Swanny
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Re: Fuel Injector upgrade

Post by Swanny »

Thanks Mike, I know I can tune in a larger injector, even if it's working a lower duty cycle,.. but do injectors change in size from brand to brand? As in, will it fit? Different brands/makes etc.

I've been stalking your website to see when the shorty radiator/intercoolers are going to be available. Any news?
Red 1985 XR4Ti

Blue 2016 XR6T Falcon Ute

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Re: Fuel Injector upgrade

Post by merkurdriver »

Injectors that look the "same" as the stock brown top in this style will all physically fit and use the same connector.
Low impedance and high impedance flavors available in this style.

Image

Any injector that "looks" different (besides color) will not be as easy to plug in and go.
Swanny wrote: Sun Aug 26, 2018 9:21 am I've been stalking your website to see when the shorty radiator/intercoolers are going to be available. Any news?
Big intercoolers are available but we are waiting for more shorty radiators to be in stock to pair them with. ( 6-8 weeks ETA )
Swanny
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Re: Fuel Injector upgrade

Post by Swanny »

Thanks Mike, I'll go injector browsing now, see what I can find to match.

And I'll be waiting for the shorty radiator/intercooler combo to be available, to be shipped to Australia. (It's going to cost me a mint!)
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Re: Fuel Injector upgrade

Post by hEaT »

Sounds like you're on a MegaSquirt so you have many options for high or low-z (like stock) injectors. I run 75lb low-z Delphi units and they work great. Idle resolution, even on MS1, is totally fine. Give yourself plenty of headroom since you have full control over fueling. What are you seeing for duty cycle currently?
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Re: Fuel Injector upgrade

Post by my8950 »

For stock type replacements, you need Bosch EV-1 Type injectors...
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Re: Fuel Injector upgrade

Post by Ed Lijewski »

Standard (Motor Products) FJ20s work perfectly in the XR and often can be found on Ebay at comparatvely lower prices.

YMMV
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Re: Fuel Injector upgrade

Post by Swanny »

hEaT wrote: Wed Aug 29, 2018 9:40 am Sounds like you're on a MegaSquirt so you have many options for high or low-z (like stock) injectors. I run 75lb low-z Delphi units and they work great. Idle resolution, even on MS1, is totally fine. Give yourself plenty of headroom since you have full control over fueling. What are you seeing for duty cycle currently?
I'm running a Stinger system, which is a Microsquirt. At the moment I'm seeing 90% duty cycle at 4750rpm, though I'm waiting for a new voltage regulator to arrive, as when it gets to this rev range, the voltage drops down to 11v, which isn't healthy, and it revs no further. I'll put in the new regulator and see if that fixes the problem.
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Re: Fuel Injector upgrade

Post by jkxr4ti »

I would suggest you look into the newer Siemens/deka high impedance injectors. These are fast opening and will work great with the MS. They draw much less current and produce less electrical noise than the low impedance injectors.
I switched to these after maxing out the stock 35lb then low impedance 42's. The ones I'm using are 83's and have the EV1 connectors. Other flows are available too. Data sheets are available for opening time etc. Wes and stinger also know and use this type so they can give you some guidance as well.
Jeremy Kemp

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MC2 Coilovers and Bushings, Contour Rims and Rotors, Ported Motorsport Head, Cosworth 4x4 Intercooler, Holset HY35 Turbo, 80LB Injectors, Megasquirt2 EFI
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Re: Fuel Injector upgrade

Post by pvan »

Ed Lijewski wrote: Wed Aug 29, 2018 3:27 pm Standard (Motor Products) FJ20s work perfectly in the XR and often can be found on Ebay at comparatvely lower prices.

YMMV
There are about 40 different FJ20 injectors. Do you know which ones are the correct 36# flow rate?

Thanks!
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Re: Fuel Injector upgrade

Post by Swanny »

jkxr4ti wrote: Sat Sep 01, 2018 10:11 am I would suggest you look into the newer Siemens/deka high impedance injectors. These are fast opening and will work great with the MS. They draw much less current and produce less electrical noise than the low impedance injectors.
I switched to these after maxing out the stock 35lb then low impedance 42's. The ones I'm using are 83's and have the EV1 connectors. Other flows are available too. Data sheets are available for opening time etc. Wes and stinger also know and use this type so they can give you some guidance as well.
Thanks Jeremy, If Wes likes them, that's good enough for me! I'll look into them, see if they have an agent over here.
Red 1985 XR4Ti

Blue 2016 XR6T Falcon Ute

Brisbane, Queensland
AUSTRALIA
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