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Firewall pass through

Bent77

Bent77

I am CK5
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Ideas on firewall pass through

Wiring bundle is ~.75”, but the PCM head is 1.5”. I hate firewall holes anyway. Only othe option is running the harness to the other side of the car and hiding it under the booster
 
I'm interested to see where this goes...
 
It takes more work but installing a pass through connector would be the cleanest option. Something like a deutsch connector.

At least you could unplug and remove the harness without fishing a connector back through the hole if you had to work on something.

AS 37 Socket Receptacle, Size 22 contacts

This Deutsch AS 37 Socket Receptacle fits size 22 contacts and features integral screen termination, a conductive black zinc finish, and universal orientation.
www.wirecare.com www.wirecare.com
 
I typically use a large rubber grommet, that's what the factory does. I don't like adding unnecessary connectors. If the harness is complete I may slice one side of the grommet to allow installation over the harness before pushing it into the hole. Once inserted if done right with the correct size hole it holds it very well.
 
The other thing I would think would work if you can't de-pin the connector would be to cut a square hole the size of the connector and then make a cover plater with a hole the size of the rubber grommet for the harness and split the plate in the middle so you can install the harness then the two halves of the plate around the wiring with a grommet that you split like Heath mentioned. Obviously you would have to either do self tapping screws for the plate or threaded inserts.
1684939067964.png
 
Truckman4life said:
The other thing I would think would work if you can't de-pin the connector would be to cut a square hole the size of the connector and then make a cover plater with a hole the size of the rubber grommet for the harness and split the plate in the middle so you can install the harness then the two halves of the plate around the wiring with a grommet that you split like Heath mentioned. Obviously you would have to either do self tapping screws for the plate or threaded inserts.
View attachment 447812
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That was the best idea I could come up with before I posted. Trying to avoid the TBI era grommets. This just look like a nerf football shoved in there.
No offense Heath!
 
ktmoutfront said:
De-pin it. Run it through and re-pin it.
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I haven’t ruled this out. It has a different style pin from all of the release tools that I have and since its EFI harness, there’s about 50 wires to unpin.
 
Depinning the ECM plugs isn't hard. I've done it with a paperclip. Good time to upgrade to a '7427 ECM!
 
No offense taken.

I don't really like the big two piece hard covers, passing through metal is what I am trying to avoid and cutting a bigger hole plus 4 screw holes is more firewall holes and more complicated than one proper sized hole with a rubber insulating grommet.

I like a grommet like this, lets me zip tie the harness to the sleeve, and is very flexible. Hole size can be up to 2.19" and could be pie sliced for smaller holes if needed. I usually have some but currently have more on the way.

1684940329798.png
 
This is why I didn't put the PF4 ECU in the cab of the C10. It's irritating the harness doesn't need nearly as large of a hole as the connector.
 
SnackPack said:
Depinning the ECM plugs isn't hard. I've done it with a paperclip. Good time to upgrade to a '7427 ECM!
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It’s an Edelbrock PF4 module
Heath do you have the tool for that?
 
mrk5 said:
This is why I didn't put the PF4 ECU in the cab of the C10. It's irritating the harness doesn't need nearly as large of a hole as the connector.
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I don’t want it under the hood. Heat
 
Seals it and Earls both have nice screw on grommets I can get, but they are more expensive than a $5 rubber grommet, these are about $30 - $50.

29g010erl_0119114.jpg
 
Bent77 said:
It’s an Edelbrock PF4 module
Heath do you have the tool for that?
Click to expand...

I have two multitools that cover most all connectors.

I have unpinned the Holley many times since it's programmable. No special tools required except a normal straight screwdriver to push the locking tab in, then all terminals come out, and you push the locking tab back from the other side by hand.

I'll examine the PF4 connector and let you know what I find out.

If you do it I recommend you take several pictures and reference the wiring diagram to confirm you have all the wires back in the proper terminal.

Also, I can see doing it just to put the correct grommet on without slicing, but for servicing reasons I don't think you want to depin the thing again. Although it's your own personal vehicle go for it. I wouldn't do that to someone else vehicle or a vehicle someone else might work on down the road.
 
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Also I can't remember, are both ends of the harness large? Trying to remember if you could feed one end thru a smaller hole.
 
mrk5 said:
I get that. Would a factory TBI pass thru grommet work?
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Yes, I've done it with that 1990 burb, but he doesn't want that look. I did use a 3/4" piece of tubing I sharpened in the lathe and heat it up my induction heater, melted a 3/4" hole right through the center.

The grommet I put above would work fine in nearly any vehicle you are willing to drill the hole in.
 
folkenheath said:
I have two multitools that cover most all connectors.

I have unpinned the Holley many times since it's programmable. No special tools required except a normal straight screwdriver to push the locking tab in, then all terminals come out, and you push the locking tab back from the other side by hand.

I'll examine the PF4 connector and let you know what I find out.

If you do it I recommend you take several pictures and reference the wiring diagram to confirm you have all the wires back in the proper terminal.
Click to expand...
Yeah I’ll nerd out and do arts and crafts as @Babaganoosh calls it
 
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