2006 5.7Hemi and 2013 8HP70 Install challenges and solutions

[Buckminster]

Good Morning all. I started a new forum post as I haven't seen some of the issues I'm encountering posted so I figured I'd share my experiences with you so you can hopefully learn without having to do this the hard way.

First off, there are a lot of different combinations out there, so here is the combination I'm using.
2006 5.7L Hemi. stock
2013 8HP70 transmission. stock
Holley Blackheart Engine mounts BHS566
Holley Blackheart transmission mount BHS567
Holley Transmission mount 71223029HKR
Holley cast iron manifolds BHS582

I chose this combination since it was supposed to minimize the need to modify the transmission tunnel.

I was planning on using the stock steering box, since i had it rebuilt by Steer and Gear and it is fantastic. However, it hit's the exhaust. I picked up a set of Jeep manifolds from the junkyard, since they were supposed to be the lowest profile smallest option as a backup. However both hit the manifold. I have ordered a Borgeson steering box, to try. On Holley's site, it does not mention that it will fit with the factory PS box. However in the instructions in one view it shows the factory box, then with the engine in, it does not show the PS box.

The notes are extensive about how to trim the suggested factory motor mounts, and having done that, they fit fine. The other thing that has conflicting information is the Hemi AC unit. In one spot it mentions having to clearance the K-frame. This is required. However, it does not say which units will fit. I have on the compressor I have a mount for a bolt at the back of the compressor. I had to remove that off the compressor for it to fit with the motor mount. Keep that in mind as your brand new compressor will have to be modified. I got mine out of a fully working car, so I was not as concerned since there was no warranty.

Those are my notes so far. As I uncover more, I'll post if you guys are interested. I plan on cleaning up the engine compartment once all the trial fitting is done, FYI.

 

[PLUM_72]

Nice start. I am doing a similar project. With the 8HP70 I had to remove/grind down about 7 tabs on the trans case for clearance in the tunnel. The trans vent with the Holley mounts is right behind the pinch weld in the tunnel. I cut away a couple inches of the pinch weld to run the vent line up to the engine. If I had to do it again, I would modify the vent location to the side. Someone out there makes a kit do do this. The Holley urethane trans mount is too tall in my opinion. The top of the case fit into the tunnel with the Holley mount, but was too close to the top of the tunnel in my opinion. I used a "short" trans mount from Energy Suspension that gave me a bit more clearance. The photo shows L to R the height differences - Holley, Energy Suspension Short, and the G-Force short mount

 

[Buckminster]

Nice start. I am doing a similar project. With the 8HP70 I had to removed/grind down about 7 tabs on the trans case for clearance in the tunnel. The trans vent with the Holley mounts is right behind the pinch weld in the tunnel. I cut away a couple inches of the pinch weld to run the vent line up to the engine. If I had to do it again, I would modify the vent location to the side. Someone out there makes a kit do do this. The Holley urethane trans mount is too tall in my opinion. The top of the case fit into the tunnel with the Holley mount, but was too close to the top of the tunnel in my opinion I used a "short" trans mount from Energy Suspension that gave me a bit more clearance. The photo shows L to R the height differences - Holley, Energy Suspension Short, and the G-Force short mount

View attachment 143888

View attachment 143889

Thank you for the feedback. I came to the same conclusion on the transmission mount. The last issue I have to resolve before I clean up my engine compartment is what steering to use. the Holley hits their cast exhaust manifold hard. I ordered a Borgeson steering box in hopes that it clears. If not, I'm not crazy about bucking up for an aftermarket tubular K-frame. What are you using for steering and exhaust? I should have mentioned that I removed the same lugs from the transmission to make it fit. I did see that on one of the Forum posts. Lastly, I cut the floor in the area of the vent and built a small dog house to close out the sheet metal. I recall the factory AC box being tight in this area, but we'll cross that bridge when we come to it.

 

[PLUM_72]

Nice solution for the vent. Call it an inspection hole. LOL! For a steering box, I am using the Borgeson. For the exhaust, I found the Holley/Blackheart headers (I began buying stuff several years back and was able to get a set). I did have to slightly dent the Blackheart headers to fit the Borgeson box. On the Borgeson box, I changed one of the four hex bolts around the sector shaft to a button head to give extra clearance for the headers. The Borgeson is smaller, but its smaller in many of the areas it doesnt need to be smaller. With the AC compressor, know that the later model factory AC compressors will not work as they are variable controlled. You need a pre-2014 compressor as those cycle on and off. Look at the Mopar/Direct Connection Crate Hemi AC add on kit. Download the instructions. In the instructions it gives the factory part number for the compressor. Then go to Rock Auto and buy a reman AC compressor that fits that P/N. I did follow the Holley instructions in their engine mount sheet and slightly trimmed one side of the bracket on the K-member. I dont think you need to do this for the AC compressor to fit, however, if you don't you may not get the back lower bolt out (or in) that attaches the AC compressor to the engine.

 

[Buckminster]

Nice solution for the vent. Call it an inspection hole. LOL! For a steering box, I am using the Borgeson. For the exhaust, I found the Holley/Blackheart headers (I began buying stuff several years back and was able to get a set). I did have to slightly dent the Blackheart headers to fit the Borgeson box. On the Borgeson box, I changed one of the four hex bolts around the sector shaft to a button head to give extra clearance for the headers. The Borgeson is smaller, but its smaller in many of the areas it doesnt need to be smaller. With the AC compressor, know that the later model factory AC compressors will not work as they are variable controlled. You need a pre-2014 compressor as those cycle on and off. Look at the Mopar/Direct Connection Crate Hemi AC add on kit. Download the instructions. In the instructions it gives the factory part number for the compressor. Then go to Rock Auto and buy a reman AC compressor that fits that P/N. I did follow the Holley instructions in their engine mount sheet and slightly trimmed one side of the bracket on the K-member. I dont think you need to do this for the AC compressor to fit, however, if you don't you may not get the back lower bolt out (or in) that attaches the AC compressor to the engine.

My engine was from a 2006, so I am planning on using the AC compressor that came with it. I had to saw off one of the casting lugs on the compressor, but figured that was an easy mod. It is ironic. I've been doing research for 2 years while my car was in the shop, and until I started looking into a solution for where to install the PCM and the Transmission controller, I didn't see any discussion about the variable compression AC compressor. But fortunately, the early compressor is supposed to work. I did make a small "doghouse" to go over the vent hole. The doghouse turned out well, but my welding leaves a bit to be desired. Thanks again for the info. I have the Holley Cast iron manifolds.