Gen3 Hemi Swap Computer Location

[inri]

Hi guys,

What place did you locate the computer/engine harness for your Gen3 Hemi in B-Body? My '69 RR has the heater box under the dash and I'd prefer to not have to remove it. I've seen in photos that many have mounted the system in that area and then popped a 2 3/4" hole in the firewall to run the wire through to the engine.

Are there any other locations that work well too? Perhaps in the engine bay or ......

Please post pics if you have them.

Thanks.

 

[Sixpactogo]

I am doing a 6.1 into a 68 Charger. The harness needs to have the computer and relays under the dash and through the firewall. My car has AC so the heater box takes up a lot of room making the install more difficult than non AC. Here are some pics of my install. It is not yet complete but should work

 

[inri]

Sixpactogo,

Your ride is coming along quite nicely. Thanks for the photos of the computer/harness mounted. Did you have to remove the heater box to drill the hole in the firewall? How long did the install take?

I'd really like to avoid removing the heater box and dash.

 

[Sixpactogo]

If your car does not have air, You have other options of where to go through the firewall. My heater box was out when I drilled the hole but I drilled it from the engine compartment. I guess it is possible but much easier with the dash and heater box out. Time wise...............still counting

 

[soundcontrol]

Seems like a good location, I got an Vinage Air unit that gonna go in, hopefuly my box will fit there also. For later tuning etc, do we need easy acess to the computer?

 

[Sixpactogo]

According to Chris at Hotwire, the harness and computer is a stand alone unit and it should be all ready to go with no need to access the relays or computer unless something fails. There is a code reader port that mounts under the dash to communicate with the computer. Hopefully that is all that is needed. Your Vintage air unit is much smaller than the factory heater box so that should open up a few different avenues for you. It sounds like you will have to remove the old heater box anyway to install the vintage air box. The dash should not need to come out to do that but it makes it much easier. The problem with taking the dash out is the windshield needs to come out to get at the dash screws under the windshield seal.

 

[mgivens710]

Just got through drilling the hole in my 68 charger. I also have vintage air in my car and I'm using a harness from Bouchillon Performance. The hole was just slightly behind and below the right hand fuel line on the passenger head. There is a dimple on the firewall there. Havent got the computer mounted yet but no problem with drilling a 2.5 inch hole there.

 

[inri]

Took out the heater core today...Came out pretty easy after I split it in two because it couldn't clear the roll bar.

Rusty and dusty, other than that pretty clean. Gonna toss it and figure out the best location for the hole in the firewall and where to mount computer now that it's pretty bare under the dash!

On a side note does anyone know if the Hellcat motor is "swappable" with a harness? I heard in the past that one day it may be? Probably pretty pricey too.

 

[inri]

Hey guys I'd like your opinion on the hole location.

On a '69 RR where is the best place to drill the firewall hole for the harness? Right where the dimple is on the first pic? The dimple is at about 9 O'clock in the interior picture. On the second pic the dimple is just to the left of the ground strap (looks like a pimple).

The hole here would keep things simple and I wouldn't have to remove any of the heater box insulation. I plan to mount the computer where the passenger kick panel was or mount it elsewhere if anyone has a suggestion.

Lastly, I've read the hole should be 2 3/4 and 2 1/2", which is it?

I'd like to keep making some progress on the car, even if its a little bit.
I'm not replacing the heater box.

 

[Sixpactogo]

Go for it. 2 1/2". Read the directions that came with your harness. That is the exact area they recommend. I would have preferred the dimple for my install also but my AC heater box would not allow for it. If you drill the hole 2 3/4" the harness grommet will not fit tight.

 

[inri]

Thanks sixpactogo. I'll plan to knock this out over the weekend!

 

[69_ply]

It looks like you have this figured out, the dimple area is where i drilled mine

 

[inri]

69_ply,
do you have a photo of where you mounted your computer harness on the interior? I've been thinking I would mount mine on the passenger kickpanel but I am open to suggestions.

Thanks for the pic, Looks great!

 

[69_ply]

I eliminated the vent on the drivers side of the car and moved all my fuse blocks there, then i mounted the computer to the brake pedal support with aluminum brackets