kinda dumb LSx wiring question

[BA.]

I've noticed on some builds using an LSx transplant that they cut a hole in the firewall that looks to be about the size of a silver dollar, directly behind the engine.

I've not noticed this on EVERY transplant, so were some of them just sneakier than the others?

Am I going to need that hole for putting the computer under the dash area?

Are there other options?

[camcojb]

I've noticed on some builds using an LSx transplant that they cut a hole in the firewall that looks to be about the size of a silver dollar, directly behind the engine.

I've not noticed this on EVERY transplant, so were some of them just sneakier than the others?

Am I going to need that hole for putting the computer under the dash area?

Are there other options?

you can put the hole wherever you want as long as the wires can make their way into the engine compartment and are long enough to reach where they need to go. I usually put mine just inside the trans tunnel so it's not really visible.

Jody

[Patrick]

I cut a hole in the trans tunnel up towards the firewall. Just make sure that you will have enough room between the bellhousing and tunnel to run the harness. I raised my tunnel about 3/4" but it may work with factory tunnel.

[WS6]

do you not have a place to tuck it away in the engine bay? You could also go with a bulk head connector but that would require a big connector and lots of time crimping pins onto wires. You be better off drilling a hole and using a grommet

[BA.]

I guess I could find a home for the computer in the engine bay. <scratch head>

I don't really know the pros/cons of either way though. Opinions welcome!

How many wires are we talking about here? Would it be a silver-dollar sized hole in the firewall, or smaller, like a quarter?


Thanks for the tips guys.

[camcojb]

I guess I could find a home for the computer in the engine bay. <scratch head>

I don't really know the pros/cons of either way though. Opinions welcome!

How many wires are we talking about here? Would it be a silver-dollar sized hole in the firewall, or smaller, like a quarter?


Thanks for the tips guys.

well, a quarter might work as far as total wire thickness, but you need to get the connections through also; the iac, injector, and tps connectors are larger for sure. I seem to remember the hole being in the 1.5" range or so.

[Malibu Jax]

I went through a similar delema on where to mount the comp. I would go with interior if possible. I spoke with a few of my mechanic friends and all of them agreed that engine bay although easier was more prone to fail (heat, moisture, vibration, dirt, etc). I still mounted mine in the bay because I used a stock harness that just did not have the length I needed for interior mount. I eventually will go back and swap out for an aftermarket when I have more money.

[CarlC]

If you use a GTO harness the ECM can be mounted in the forward LH side of the fenderwell. I used an F-body ECM mount with a few bolts to hold it there. It just barely fits.

[Camaross82]

Who is making the after market harnesses. and how many connections do I need for a LS1/M6?

[Malibu Jax]

Painless and few others make aftermarket. They are available with additional length so interior mounts are eaiser.

[BA.]

It's kind of coincidental that this was already brought up for me and I didn't have to go looking for it.

I came across this great picture today of the hole in the firewall I am referring to.
I wanted to post it to see if anyone had could say whether it's in a good/desireable location or not. Seems to be, but I was just looking for confirmation.

[67 ls1 vert]

Nice find on the photo! I have wanted to see a picture like that for a long time. I would love to other idea's too.

[Kokamo]

Ok gents, I have been wanting to share my idea, but it was done in a kinda cheesy fashion, and I wanted to spare my embarrassment, but I changed my mind ........

Ok, I have a 69 Camaro....LS1/T56 with STOCK harness I modified. I simply cut a square hole in the firewall very close to the same place as the above pic, and made a kind of tunnel for the wires to travel thru (see pic below). Then I built a cover and integrated a twp piece "Seals-It" grommet to the cover.

The worst part of this mod is modifying the harness. I had to shorten some wires, and then lengthen other wires. It's very time consuming, but the final product is very well worth it. You cannot even tell there is a harness going to the engine as EVERYTHING is hidden from view.

Any questions? I'll help if I can.

~Joe

[youthpastor]

i like that plug- who sells it??

[Kokamo]

i like that plug- who sells it??

A plug? You mean grommet? It's made by Seals-It.....and Summit racing sells them.....CLICKY CLICKY. They also sell an entire line of different styles of grommet seals. From split grommet like the one above, to circular styles with pre-cut holes....make your choice.

~Joe

[BA.]

Those are great pictures Kokamol. Since I don't actually HAVE my motor yet, that picture you have of the back of the engine just speaks volumes.

I think your solution there is really well done, NOT cheesy! The finished result is so worth the effort.

[Kokamo]

Those are great pictures Kokamol. Since I don't actually HAVE my motor yet, that picture you have of the back of the engine just speaks volumes.

I think your solution there is really well done, NOT cheesy! The finished result is so worth the effort.

Thanks man. The reason I was thinking it was cheesy is because it was done with almost ZERO dollars spent. All fabrication with the exception of the grommet. To be honest, I don't know of any other way to do it and make it perfectly hidden at the same time....regardless of spending any money.

Thanks for the comment bro. Good luck with your build. Lemmie know if I can help.

~Joe

[youthpastor]

A plug? You mean grommet? It's made by Seals-It.....and Summit racing sells them.....CLICKY CLICKY. They also sell an entire line of different styles of grommet seals. From split grommet like the one above, to circular styles with pre-cut holes....make your choice.

~Joe

sweet!!