280z EFI harness hole size

[Dave WM]

In the firewall that is. I am trying to source a grommet for my turbo harness. Went the the JY today, got something that may work, most were too large as I think it is a 2.5" hole in the fire wall based on some rather poor measurements taken with the plug installed and me on my back in the foot well....

I saw some old threads IIRC there was a 2.5" hole mentioned. 

My follow up will be do you push the connectors intact thru the opening one at a time (seems like some of them would be too large), does the grommet stretch that much? if it does do you go with put the passenger side connectors thru the hole or the engine compartment connectors? The turbo may hava a slight advantage on the passenger side connectors since they are broken up into smaller chunks that the single 35 pin connector used on the NA engines. 

[Dave WM]

maybe this as a start?

GR3145A Essentra | Mouser

[Yarb]

Shipping will cost more than the grommets. Buy a few!!

[HusseinHolland]

Are we talking about the large grommet that the main harness passes through into the bay? Mine is torn, so I've been figuring out if I can use a Volvo grommet I already have. I would say the ones linked from Mouser are less than ideal - the factory grommets have a tube of sorts that allows for harness movement & also a downward angle on the bay side, to help keep water from tracking through to the cabin.

I'm considering slicing the grommet, as I'm NOT removing the harness to feed through a new grommet. Not ideal, but better than a grommet with the torn 'tube' section.

Edited September 21, 2023 by HusseinHolland

[Yarb]

Aftermarket grommets are available. ZCar Depot & jdm here’s a link from jdm

https://jdm-car-parts.com/products/engine-harness-fire-wall-grommet-for-1973-1978-240z-260z-280z

[Dave WM]

says good for 73-78, I thought the 280z had a larger hole, will contact them to be sure.

Called him says it will fit the 78 so I assume the hole size remained unchanged 73-78. 

If anyone has used one of those from the link, please chime in on any issues. 

 

Edited September 21, 2023 by Dave WM

[Dave WM]

well decided to try my JY find, a literal pick up off the ground, anyway I was able to open up the inside to a nice fit with a step drill (rubber was pretty hard, but it worked ok). then used a saw to open up so I could just fit around the harness without all the drama of trying to fit stuff thru. This will probably work to my advantage on the sizing as well since it seemed just a bit to large for the 2.5 hole, so the kerf should bring it down some. I can widen the kerf if needed. I can always glue it back up with the kerf pointed downward on the final install. There are some rubberized super glues that work well to glue it shut after test fitting. a little silicone and some harness tape should make for a fine water proof seal. 

[HusseinHolland]

I cut mine out, after checking that the hole was 2.5" - The Volvo one measured @ 2.4" in the lip, and the original appeared to be the same, but... once cut the new one is floppy in the hole 😞

VO 3515008

I'll have to order a proper one 

[HusseinHolland]

6 hours ago, Yarb said:

Aftermarket grommets are available. ZCar Depot & jdm here’s a link from jdm

https://jdm-car-parts.com/products/engine-harness-fire-wall-grommet-for-1973-1978-240z-260z-280z

Couldn't find one on Zcar for the 280 - so I looked at the JDM link - $49(!) for a grommet, just a little pricy 🤪

[Yarb]

$45, Free Shipping and no Tax. True a bit pricy. I think the more you run into parts that are NLA and are wearable items you find yourself paying a lot extra for these Zcars. I ordered one for mine today. I’ll pass on the quality and how it compares to factory.

 

[dutchzcarguy]

Often it's much cheaper to order a whole box with rubber ring's and grommet's. I remember i did this myself long ago and it comes always handy to have them in your garage.

[HusseinHolland]

9 hours ago, Yarb said:

$45, Free Shipping and no Tax. True a bit pricy. I think the more you run into parts that are NLA and are wearable items you find yourself paying a lot extra for these Zcars. I ordered one for mine today. I’ll pass on the quality and how it compares to factory.

 

If I were doing a resto & feeding a new harness, I would bite the bullet. Cutting a $49 grommet to fit around the old harness, I just can't bring myself to do it. I ordered an assortment of (ugly) generic grommets that cover the 60-70mm size range.