Installing fuel injectors - ZR-1 Net Registry Forums

mmkkpro · 08-02-2019

Good morning guys, I have a question about installing fuel injectors. Do you take the fuel rails apart when installing the new injectors? The shop manual is not real clear about that, thanks.

Ccmano · 08-02-2019

After you remove the plenum, you will see 4 10mm bolts that hold down the fuel rail. Remove them. Make sure you depressurize the rail by depressing the Schrader valve at the end of the pass side rail. Have plenty of rags ready to soak up gas. Leave the fuel lines attached to the fuel rails. You will be flipping the entire assembly up and over on to the windshield (or wherever it wants to easily go) once removed. I use a slim hammer handle (something strong but soft enough to not marr the injector housing when you pry) to pry the fuel rail assembly up with the injectors attached. The whole assembly should simply pop up and out with injectors still attached to the rail. Take your time, it may require some gentle persuasion in places. Normally they pop out without too much effort. However I have had at least one where the injector O-rings got so hard they didn’t want to release from the IH. Again go slow and work from the ends to pop out one injector at a time, they will come. Here’s a picture of what it should look like when your done with the removal.
Good luck
H

Jagdpanzer · 08-02-2019

You can squirt some WD40 at the base of the injectors where they insert into the injector housing. Then work the rails around a bit to help the O-rings release. Then proceed as Hans suggests above.

Sent from my iPhone using ZR-1 Net Registry

mmkkpro · 08-02-2019

Thank yall very much, going to tackle it in the morning, I'm old school carburetor guy and haven't really done a lot of fuel injection stuff. I appreciate the info very much! Getting closer to firing her up👍👍🏁

Paul Workman · 08-04-2019

It appears to be a 1990 ZR-1, which has also been ported. (NICE!). Same here!

Injector sources:

FIC can fix you up with the STAINLESS STEEL injectors and the appropriate seals (O-rings and plenum gaskets, etc provided by Jerry's Gaskets (a source you should get to know!). Or, as I and many have done, install the Accel injectors #150821 from Summit Racing* (Mine I installed myself in 2010?) and they are working just fine!)

*There is a plastic indexing nub on the Accel injectors that needs to be removed ONLY on those injectors going into the secondary ports. 5 minutes with a Dremel for all 8 was all it took and the connector will snap right on - no problem!

-=Jeff=- · 08-05-2019

Quote:

Originally Posted by Paul Workman

It appears to be a 1990 ZR-1, which has also been ported. (NICE!). Same here!

Injector sources:

FIC can fix you up with the STAINLESS STEEL injectors and the appropriate seals (O-rings and plenum gaskets, etc provided by Jerry's Gaskets (a source you should get to know!). Or, as I and many have done, install the Accel injectors #150821 from Summit Racing* (Mine I installed myself in 2010?) and they are working just fine!)

*There is a plastic indexing nub on the Accel injectors that needs to be removed ONLY on those injectors going into the secondary ports. 5 minutes with a Dremel for all 8 was all it took and the connector will snap right on - no problem!

Paul the posted Picture is Hans' Car

32valvZ · 08-05-2019

Quote:

Originally Posted by -=Jeff=-

Paul the posted Picture is Hans' Car

Stupid hip replacement meds are prolly clouding his vision... ask me how I know....

mmkkpro · 08-04-2019

Good morning Paul, first thank you for your reply, I really appreciate all your guys help. I did buy my gaskets from Jerry, he straightened out my order for me and saved me some money, so that was great. Trying to test my secondary parts today, new vacuum pump installed and seems to be running properly. Slowly getting there.
It is a 1990, how can you tell if its been ported? I have tried to contact the original owner without success, so I really know next to nothing about its history other than what the guy I bought it from has told me. Thanks

Z51JEFF · 08-05-2019

Before you put the plenum back on you do want to check the secondary’s and you might want to pressurize the fuel rails to make sure there are no leaks. ITS BEEN AWHILE SINCE IVE DONE THIS SO IF DOING THIS ISN'T AN TOOD IDEA,somebody please advice on this. I remember checking the system when I did my injectors years ago. I can’t remember how to energize the secondary system through the ignition key but that’s the best process,somebody here might know how to do that.

Paul Workman · 08-06-2019

Quote:

Originally Posted by mmkkpro

It is a 1990, how can you tell if its been ported? I have tried to contact the original owner without success, so I really know next to nothing about its history other than what the guy I bought it from has told me. Thanks

DOH! (palm slap to forehead!) Yes, (thanks to Jeff - [he's so kind, ain't he?]

), and yes, I am on post-op meds

I see now it IS Han's motor.

The runners of a stock (non-ported) 1990-92 are ~ 33mm diameter on primaries, and 36mm on secondaries. Once the Injector Housing (aka "IH") runners have been ported they BOTH will be ~36+mm in diameter, OR even partially or completely "siamesed". Han's runners are obviously - or appear to me anyway - to be uniformed AND appear to have the traces of scoring left by the tooling used to do the porting.

Oh, and why do porting?? Well....HORSEPOWER! The stock LT5, especially the 90-92s were starving for air. Porting alone, coupled with necessary fueling adjustments for the added air volume can buy you an extra 100+ "free" horsepower and bring you to ~ 490 crank hp w/o loosing any of the drivability you'd likely experience if you tried that with any (SBC) pushrod motor.

And with headers, "X-pipe" (and eliminating the resonator), it is common place now to see 510-520+ hp on stock cams, stock idle, ALL the accessories (AC) working as before! Re-ground cams, sleeves, etc.? Welcome to the BEAST!

Oh, and while we're on it, the DOHC LT5 will wind to 7000 rpm, and as Dave Mclellan once said regarding revving to the limit: "it (the LT5) will thank you for it!"

AND, after porting, something our own renown FBI guy and post production LT5 developer, Pete Polatsidis, put me onto is the look on people's faces when you do a 5-2 downshift at ~ 45-50 mph and stand on it to 7000+ rpm!* It will really wipe the smirk off the face of a LOT of wise-azz push-rod junkies!

* 90 mph w/ stock rear end

What's not to like?

08-02-2019	#2
Ccmano Join Date: Jun 2006 Location: Sparks, NV Posts: 2,843	Re: Installing fuel injectors After you remove the plenum, you will see 4 10mm bolts that hold down the fuel rail. Remove them. Make sure you depressurize the rail by depressing the Schrader valve at the end of the pass side rail. Have plenty of rags ready to soak up gas. Leave the fuel lines attached to the fuel rails. You will be flipping the entire assembly up and over on to the windshield (or wherever it wants to easily go) once removed. I use a slim hammer handle (something strong but soft enough to not marr the injector housing when you pry) to pry the fuel rail assembly up with the injectors attached. The whole assembly should simply pop up and out with injectors still attached to the rail. Take your time, it may require some gentle persuasion in places. Normally they pop out without too much effort. However I have had at least one where the injector O-rings got so hard they didn’t want to release from the IH. Again go slow and work from the ends to pop out one injector at a time, they will come. Here’s a picture of what it should look like when your done with the removal. Good luck H

08-02-2019	#3
Jagdpanzer Join Date: Apr 2007 Location: Northern VA Posts: 2,646	Re: Installing fuel injectors You can squirt some WD40 at the base of the injectors where they insert into the injector housing. Then work the rails around a bit to help the O-rings release. Then proceed as Hans suggests above. Sent from my iPhone using ZR-1 Net Registry __________________ Phil Wasinger 1994 Torch Red ZR-1 WAZOO Member George Braml Intake

08-02-2019	#4
mmkkpro Join Date: Apr 2019 Location: Supply NC Posts: 124	Re: Installing fuel injectors Thank yall very much, going to tackle it in the morning, I'm old school carburetor guy and haven't really done a lot of fuel injection stuff. I appreciate the info very much! Getting closer to firing her up👍👍🏁 Last edited by mmkkpro; 08-02-2019 at 07:30 PM.

08-04-2019	#5
Paul Workman Join Date: Nov 2007 Location: Squires (near Ava MO in the Mark Twain N'tl Forest) - Missouri Posts: 6,466	Re: Installing fuel injectors It appears to be a 1990 ZR-1, which has also been ported. (NICE!). Same here! Injector sources: FIC can fix you up with the STAINLESS STEEL injectors and the appropriate seals (O-rings and plenum gaskets, etc provided by Jerry's Gaskets (a source you should get to know!). Or, as I and many have done, install the Accel injectors #150821 from Summit Racing* (Mine I installed myself in 2010?) and they are working just fine!) There is a plastic indexing nub on the Accel injectors that needs to be removed ONLY on those injectors going into the secondary ports*. 5 minutes with a Dremel for all 8 was all it took and the connector will snap right on - no problem!

08-04-2019	#8
mmkkpro Join Date: Apr 2019 Location: Supply NC Posts: 124	Re: Installing fuel injectors Good morning Paul, first thank you for your reply, I really appreciate all your guys help. I did buy my gaskets from Jerry, he straightened out my order for me and saved me some money, so that was great. Trying to test my secondary parts today, new vacuum pump installed and seems to be running properly. Slowly getting there. It is a 1990, how can you tell if its been ported? I have tried to contact the original owner without success, so I really know next to nothing about its history other than what the guy I bought it from has told me. Thanks

08-02-2019	#1
mmkkpro Join Date: Apr 2019 Location: Supply NC Posts: 124	Installing fuel injectors Good morning guys, I have a question about installing fuel injectors. Do you take the fuel rails apart when installing the new injectors? The shop manual is not real clear about that, thanks.

08-05-2019	#9
Z51JEFF Join Date: Dec 2007 Location: Fremont, CA Posts: 3,087	Re: Installing fuel injectors Before you put the plenum back on you do want to check the secondary’s and you might want to pressurize the fuel rails to make sure there are no leaks. ITS BEEN AWHILE SINCE IVE DONE THIS SO IF DOING THIS ISN'T AN TOOD IDEA,somebody please advice on this. I remember checking the system when I did my injectors years ago. I can’t remember how to energize the secondary system through the ignition key but that’s the best process,somebody here might know how to do that.