Finally get to pretend I am one of the cool kids - Holley kit swap

[72bluNblu]

I understand. I like the idea that I don't have to weld a seam all along the floor, but in the end a one piece tunnel welded all the way around probably is less welding in the end. Time will tell.

I don't think the 8HP tunnel is anywhere close to the size of one that fits a T56 in my case either. The T56 seems to be much taller just looking at how far up into the firewall my cuts are compared to yours.

If I were to do a one piece tunnel, I would consider a tunnel out of a late model Mopar like @Cool Hand did here.

But I wouldn't want it to go so far back. And it would be buckets only.

And no idea where I would even source the tunnel.

You won't have to take the tunnel modifications back as far as they did with that late model tunnel, but they do have to go back pretty far. Mine goes pretty much all the way back to the front of the floor reinforcement for the rearmost bucket seat mounts. The removable panel behind my shifter is open in the center so the shifter (not the handle) can be in place when the transmission is installed or removed. I did that so that I could install/remove the transmission by itself without having to angle it down like 1° at a time while I was sliding it back out of the bell. Otherwise the shifter stub would hit the tunnel. The way mine is set up it can come pretty much straight back until the input shaft is almost entirely out of the bell before you have to start dropping it down. If anything, if I were to do it again I would probably take that opening back another couple inches.

I run the A-body console in mine, it sits further back than the factory location to line the shifter up with the console. Doesn't leave a ton of space for the Procar seats, but there is some.

 

[Dantra]

You won't have to take the tunnel modifications back as far as they did with that late model tunnel, but they do have to go back pretty far. Mine goes pretty much all the way back to the front of the floor reinforcement for the rearmost bucket seat mounts. The removable panel behind my shifter is open in the center so the shifter (not the handle) can be in place when the transmission is installed or removed. I did that so that I could install/remove the transmission by itself without having to angle it down like 1° at a time while I was sliding it back out of the bell. Otherwise the shifter stub would hit the tunnel. The way mine is set up it can come pretty much straight back until the input shaft is almost entirely out of the bell before you have to start dropping it down. If anything, if I were to do it again I would probably take that opening back another couple inches.

View attachment 1716347559

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I run the A-body console in mine, it sits further back than the factory location to line the shifter up with the console. Doesn't leave a ton of space for the Procar seats, but there is some.
View attachment 1716347561

I like the shape!

 

[Ozyduster]

Did i read that you have to cut the fire wall? With the hollley mounts you shouldn't have to cut the firewall at all sue to engine moving forward?

 

[DionR]

Did i read that you have to cut the fire wall? With the hollley mounts you shouldn't have to cut the firewall at all sue to engine moving forward?

Yes, I had to cut forward of the pinch weld. I lost some time trying to figure out why since I assumed that with the motor forward I wouldn’t have to cut as much. But I think Holley didn’t just move the motor forward, they moved it up about 3/4” as well.

Also, I have the big cast aluminum bell which doesn’t help any. The QuickTime bell is shorter at the top of the trans and might make a decent difference.

I have enough room for my factory heater box, but not sure about a factory AC box. I documented some of the things earlier that setting the motor up did. Not saying they were absolutely necessary, but the stuff Holley built around that motor location would make it tough to lower it.

I have in the back of my mind that if I like the Hemi enough, I could see swapping the motor into my ‘74 with the A833OD using the Holley stuff and doing more of an edgier build and using different mounts and headers to set the motor back and down for better weight. But that is just an idea and for now I am ok with the compromises.

 

[340sFastback]

I cut my firewall pinch weld out of trans tunnel and butt welded custom tunnel to that. Nice and smooth looks a lot better that way to get rid of pinch weld all together.

 

[DionR]

I cut my firewall pinch weld out of trans tunnel and butt welded custom tunnel to that. Nice and smooth looks a lot better that way to get rid of pinch weld all together.

In the end, most of my pinch weld will get removed as well.

 

[340sFastback]

In the end, most of my pinch weld will get removed as well.

I first bent mine over, struggled to get huge cast aluminum bell housing to fit, then my wife yelled at me and said go buy the Quick Time. I said ok if you say so. Then sold cast bell housing to someone on here who wanted it.

 

[DionR]

I first bent mine over, struggled to get huge cast aluminum bell housing to fit, then my wife yelled at me and said go buy the Quick Time. I said ok if you say so. Then sold cast bell housing to someone on here who wanted it.

I have your swap bookmarked and remember when you were struggling with getting your AC box to fit since the cast aluminum bell was taller.

 

[racerjoe]

Yes, I had to cut forward of the pinch weld. I lost some time trying to figure out why since I assumed that with the motor forward I wouldn’t have to cut as much. But I think Holley didn’t just move the motor forward, they moved it up about 3/4” as well.

Also, I have the big cast aluminum bell which doesn’t help any. The QuickTime bell is shorter at the top of the trans and might make a decent difference.

I have enough room for my factory heater box, but not sure about a factory AC box. I documented some of the things earlier that setting the motor up did. Not saying they were absolutely necessary, but the stuff Holley built around that motor location would make it tough to lower it.

I have in the back of my mind that if I like the Hemi enough, I could see swapping the motor into my ‘74 with the A833OD using the Holley stuff and doing more of an edgier build and using different mounts and headers to set the motor back and down for better weight. But that is just an idea and for now I am ok with the compromises.

It just occurred to me that they may have raised the engine for alternator clearance at the front frame rail pinch weld when using the car front cover.

 

[DionR]

It just occurred to me that they may have raised the engine for alternator clearance at the front frame rail pinch weld when using the car front cover.

Could be. I haven't tried an alternator on the motor yet to see.

I was guessing they did it to fit a bigger oil pan. The stock A-Body pan is like 3 or 4 quarts, this one is 6 quarts and hangs below the k-frame about 1/2" even with the motor sitting up.

 

[Dantra]

I have enough room for my factory heater box, but not sure about a factory AC box.

if I like the Hemi enough...

I ditched the oem AC box for aftermarket.. for a few reasons. The factory box is just an space hog and it looked like there was just going to be too many clearance issues.I could barely get it back in, just after increasing my tunnel size just a little was one. Also, if I had gone much bigger, the floor duct would have been a big deal. Another reason is, I just didn't see enough room for the dbw pedal. I was ready to upgrade anyway. I just felt like I was constant battle to get cold air. It would be fine.. then it wouldn't. But space was was the biggest factor, since all of my electronics are housed in the dash. I played around with the USCT pedal bracket over the weekend. I'll post in my thread here in a bit. You'll see that the pedal needs that room that the ac box wants as well..

"if I like the hemi enough"... @racerjoe , would you like to chime in here LOL. I think all of us have sold all of our small block parts and will never look back.