Installing fuel injectors - Page 2 - ZR-1 Net Registry Forums

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?

mmkkpro · 08-06-2019

Sounds good to me, thanks for the education lesson. From the looks of the secondary injectors who ever was driving it rarely opened her up, will not have to worry about that now. I plan on getting her right and driving the wheel off her, like she was built to do. I'm saving for a performance chip from Marc now, he has also been very helpful to me doing this project.

mmkkpro · 08-11-2019

Good morning guys, can somebody clue me in on what gets ported on the top end. I measured the top of the runners in the injector housing and came up with 16.11 mm, the air horn in front of the throttle body measured 36mm, just curious, thanks

mmkkpro · 08-11-2019

Here is a Pic of the measurement, the read out says one thing but if you look at the black scale it says around 33mm, in no professional so my measurements or tool could be off a little, thanks.

Jagdpanzer · 08-11-2019

After turning the calipers on close it all the way then hit the Zero button and try measuring the ports again. If the readings still appear off it’s time for new digital calipers.

mmkkpro · 08-11-2019

Thanks Jagdpanzer, I did zero them a couple times, they are kinda old, the black scale reads 33mm, they were packed away and I forgot to remove the battery so must have cooked the digital readout. Time for a new one. Thanks.

Ccmano · 08-11-2019

This thread is a good read if you thinking of porting.
H

http://www.zr1.net/forum/showthread....hlight=Porting

mmkkpro · 08-11-2019

Small success to report, filled her with fuel, turned on the switch, no fuel pressure. So I ran a hot wire to the small connector by the windshield and heard my pump, knowing fuses were good I switched out the horn relay for the FP1 relay and instant fuel pressure and no leaks on injectors or fuel rail. Putting plenum on now and plan to prime the oiling system this week and try starting her Saturday. Thank all you guys for all the help, I'm starting to see light at the end of the tunnel! 👍👍🏁

Ccmano · 08-11-2019

Quote:

Originally Posted by mmkkpro

Small success to report, filled her with fuel, turned on the switch, no fuel pressure. So I ran a hot wire to the small connector by the windshield and heard my pump, knowing fuses were good I switched out the horn relay for the FP1 relay and instant fuel pressure and no leaks on injectors or fuel rail. Putting plenum on now and plan to prime the oiling system this week and try starting her Saturday. Thank all you guys for all the help, I'm starting to see light at the end of the tunnel! 👍👍🏁

Curious, how are you priming the oiling system?
H

mmkkpro · 08-11-2019

I have been in touch with Marc and he turned me on an article he wrote about starting these cars that have been sitting. He uses a small tank with air fittings to push 3 quarts into the engine by way of the oil pressure sensor port. It looks like a propane takes sorta. They cost a couple hundred bucks, I think in going to make my own rig though. I've searched YT and some of these guys that do this to LS engines have some good ideas.

08-06-2019	#12
mmkkpro Join Date: Apr 2019 Location: Supply NC Posts: 124	Re: Installing fuel injectors Sounds good to me, thanks for the education lesson. From the looks of the secondary injectors who ever was driving it rarely opened her up, will not have to worry about that now. I plan on getting her right and driving the wheel off her, like she was built to do. I'm saving for a performance chip from Marc now, he has also been very helpful to me doing this project.

08-11-2019	#13
mmkkpro Join Date: Apr 2019 Location: Supply NC Posts: 124	Re: Installing fuel injectors Good morning guys, can somebody clue me in on what gets ported on the top end. I measured the top of the runners in the injector housing and came up with 16.11 mm, the air horn in front of the throttle body measured 36mm, just curious, thanks

08-11-2019	#15
Jagdpanzer Join Date: Apr 2007 Location: Northern VA Posts: 2,646	Re: Installing fuel injectors After turning the calipers on close it all the way then hit the Zero button and try measuring the ports again. If the readings still appear off it’s time for new digital calipers. __________________ Phil Wasinger 1994 Torch Red ZR-1 WAZOO Member George Braml Intake

08-11-2019	#16
mmkkpro Join Date: Apr 2019 Location: Supply NC Posts: 124	Re: Installing fuel injectors Thanks Jagdpanzer, I did zero them a couple times, they are kinda old, the black scale reads 33mm, they were packed away and I forgot to remove the battery so must have cooked the digital readout. Time for a new one. Thanks.

08-11-2019	#17
Ccmano Join Date: Jun 2006 Location: Sparks, NV Posts: 2,843	Re: Installing fuel injectors This thread is a good read if you thinking of porting. H http://www.zr1.net/forum/showthread....hlight=Porting

08-11-2019	#18
mmkkpro Join Date: Apr 2019 Location: Supply NC Posts: 124	Re: Installing fuel injectors Small success to report, filled her with fuel, turned on the switch, no fuel pressure. So I ran a hot wire to the small connector by the windshield and heard my pump, knowing fuses were good I switched out the horn relay for the FP1 relay and instant fuel pressure and no leaks on injectors or fuel rail. Putting plenum on now and plan to prime the oiling system this week and try starting her Saturday. Thank all you guys for all the help, I'm starting to see light at the end of the tunnel! 👍👍🏁

08-11-2019	#20
mmkkpro Join Date: Apr 2019 Location: Supply NC Posts: 124	Re: Installing fuel injectors I have been in touch with Marc and he turned me on an article he wrote about starting these cars that have been sitting. He uses a small tank with air fittings to push 3 quarts into the engine by way of the oil pressure sensor port. It looks like a propane takes sorta. They cost a couple hundred bucks, I think in going to make my own rig though. I've searched YT and some of these guys that do this to LS engines have some good ideas.