Injector Ohms
 

1982 280 zxt, Im replacing Injectors. Car is totally stock

The original ones are 3.6 Ohms 265 cc

New ones are 14.5 Ohms 330 cc@ 43 Psi

They look the same, at least in color, My car runs around 30 psi at idle

If I did the math correctly, The cc @ 30 psi would be around 245 cc

Are these going to work,
Will the Ohms screw anything up, being higher.

Any help would be nice.
Charles

Welcome to ZDriver!

Yes, technically they will work, but without any other adjustments it's going to run rich. I am running 308cc high impedance on my L28ET, but using the Z31T ecu, maf, and T3/T4 turbo. You'll probably still need to adjust the afm even running at 30psi fuel pressure.

Thanks for the info, I sent them back before I installed them. Dont think the ecu would play nice with them, and Ive had just about ever problem you can have. I see your running a different ecu, guess thats why you can run high impedance injectors.

Guess I will send them off to be cleaned, tho the car runs great, it seems to stumble a little bit when starting, thinking leaking injector, plus they are original 35 years old and still clicking away. I need to install a A/F meter...next project I guess !
Again Thanks

You can run high impedance injectors on a low impedance ecu, just not low impedance injectors on a high impedance ecu.

Cold start stumble would either be the air regulator, or aac.
Have you checked timing? Cold start fuel pressure (test for leak down)?
Read spark plugs?

The fuel does leak down after say 30 minutes, I put a fuel check valve so the fuel could not bleed back through the fuel pump, so now it takes about 1 hour to bleed down. I was thinking it could be the fuel pressure reg, When I go to start my car, I allow the pump to get pressure up and then I start. It was around 30 when trying to start, so I installed a adjustable fuel pressure regulator, Bingo ....I set it to 37 PSI, basically WOT, seeing how At that point I have no Vac, started right up nice. But I cant seem to get the return line connection at the reg to stop leaking ( small ), but still leaking. Guess Im going to relocate it away from the rail, just so I can actually check and work on it. I like where it is now, but if you cant work and check easily what good is it. But it still leaks down. Also is there a range used for the injector impedance. Say like mine are listed in the FSM at 2.7 and they are say 3.5, is there a rule of thumb, that you need to stay within ? say 2 Ohm one way or the other.
Thanks for all the Info, helps me alot. I find this car challenging , And I guess I enjoy the challenge.

So, I could not get the return fitting on the regulator to stop leaking, 30.00 piece of junk, remembered I bought a Micro Dynamics regulator of EBAY along time ago, went and dug it out of my parts stash, Installed it, Now everything seems ok, If I set it to 30 psi at idle, when I stab the throttle like WOT it goes to 43/44, So I set it down to about 27 at idle , now Im getting 38/39 at WOT, seems to idle smoothly. wish I had a A/F meter to really see what going on. Does that sound like it will work ?

Follow Up
 

So I brought some used turbo injectors off E Bay many years ago, Got them all together and took them to a local Injector rebuilder
He checked them out , said as far a ohms resistance they were perfect, as far as clean they were terrible, but he got them flowing
perfect. I removed my Factory fuel rail, and installed one from Pallet, with all new hoses and fuel line clamps. The difference is Day and Night
It seemed to run ok before, now it screams. Did a Ohms test on the ones that came out, One didnt show any ohms at all, one was way high.

Thought I would ad this to the thread.

Excellent follow up! Indeed injectors play a major role in how well the engine runs. Seems that the turbo engines have a lot more injector problems. :)