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

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Finally got some pictures of my setup. Looks to be around 1/4" for me as well. You can see the one trimmed stud and it does look like I just shaved the plastic tower around it

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Not sure if you have it listed in here but are you offsetting the booster and what size are you going to run. As about to purchase all my brake set up items. Dr diff sell the offset brackets and maybe a small booster not sure if needed tho
 
Not sure if you have it listed in here but are you offsetting the booster and what size are you going to run. As about to purchase all my brake set up items. Dr diff sell the offset brackets and maybe a small booster not sure if needed tho
Not sure what Dion has planned but I was able to just keep the setup I that I put in before the Hemi swap.. Ebay special!

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Not sure if you have it listed in here but are you offsetting the booster and what size are you going to run. As about to purchase all my brake set up items. Dr diff sell the offset brackets and maybe a small booster not sure if needed tho

I pulled the factory style power brake booster and will be running manual brakes. That what I run on my '74 and even with too large of a master cylinder I like it.

No offset, motor fits fine with the MC in the stock location.
 
Man, progress has been so slow. Partly because I spend way too much time overthinking things, partly because it is cold out and partly because the holidays took a bunch of time.

But I am close to finally cutting some sheetmetal for the trans/bell. So maybe some real progress soon, hopefully before the new year.

Either way, couple of things I have learned as I beat my head against the wall.

A; it appears that the Holley mounts don't just set the motor forward, but they also put it higher by about 3/4". The TTI measurements say the crank should be 5.25" above the top of the k-frame, I am getting 6". I suspect that the 90 degree oil filter adapter wouldn't fit as well without this lift, but just a guess. I know the oil pan doesn't have enough room to come down that much either. I'm not going to do anything about it, but it explains why I felt like I was going to have to cut my firewall more than I expected since the motor was forward 1.75".

2; for anyone else looking at doing this swap, I am setting my motor at 3 degrees. Based on some semi-accurate measurements and layouts, it looks like I can keep my u-joint angles happy at that inclination. I looked at 2, 2.5 and 4 degrees down and all of them had issues with u-joint angles. I know this is just a guess right now and I will look at it again before I weld anything solid, but it looks like 3 degrees down will work with just about any pinion angle while the others wouldn't. This probably only applies to swaps using the Holley mounts though. And yes, the car is sitting at close to ride height.

D; the pinion angle on my stock 8.25" is weird. Everything I read says the pinion and engine angles should be close to parallel and best guess the stock engine would be about 4 degree down, but the pinion angle is just under a half a degree up (or opposite the engine slope). I know with a leaf spring suspension, you want it to be able to wrap up some and come into alignment but 4.5 degrees off? Something seems off.

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Man, progress has been so slow. Partly because I spend way too much time overthinking things, partly because it is cold out and partly because the holidays took a bunch of time.

But I am close to finally cutting some sheetmetal for the trans/bell. So maybe some real progress soon, hopefully before the new year.

Either way, couple of things I have learned as I beat my head against the wall.

A; it appears that the Holley mounts don't just set the motor forward, but they also put it higher by about 3/4". The TTI measurements say the crank should be 5.25" above the top of the k-frame, I am getting 6". I suspect that the 90 degree oil filter adapter wouldn't fit as well without this lift, but just a guess. I know the oil pan doesn't have enough room to come down that much either. I'm not going to do anything about it, but it explains why I felt like I was going to have to cut my firewall more than I expected since the motor was forward 1.75".

2; for anyone else looking at doing this swap, I am setting my motor at 3 degrees. Based on some semi-accurate measurements and layouts, it looks like I can keep my u-joint angles happy at that inclination. I looked at 2, 2.5 and 4 degrees down and all of them had issues with u-joint angles. I know this is just a guess right now and I will look at it again before I weld anything solid, but it looks like 3 degrees down will work with just about any pinion angle while the others wouldn't. This probably only applies to swaps using the Holley mounts though. And yes, the car is sitting at close to ride height.

D; the pinion angle on my stock 8.25" is weird. Everything I read says the pinion and engine angles should be close to parallel and best guess the stock engine would be about 4 degree down, but the pinion angle is just under a half a degree up (or opposite the engine slope). I know with a leaf spring suspension, you want it to be able to wrap up some and come into alignment but 4.5 degrees off? Something seems off.

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If I remember correctly, mine is around 3 degrees. It was never right after I installed the TKO. Someone once mentioned to me the old school TKO500 conversion kits (Kiesler Mfg.) always had the angle wrong. At one point, I shimmed the trans mount up until the trans was hitting the tunnel I modified to work with their mount. It was marginally better, but with my lowered ride height, I knew I'd have to cut the tunnel and rebuild it. When I did the hemi swap, I cut the tunnel out, shimmed the trans and rebuilt the tunnel. I want to say I have a 3/4"-1" shim on the mount. Talk about way off! I can do well over 100mph now with no driveline vibration. Note, I don't think the too low trans mount would be a problem for guys running super stock springs with the *** end up in the air.
 
If I remember correctly, mine is around 3 degrees. It was never right after I installed the TKO. Someone once mentioned to me the old school TKO500 conversion kits (Kiesler Mfg.) always had the angle wrong. At one point, I shimmed the trans mount up until the trans was hitting the tunnel I modified to work with their mount. It was marginally better, but with my lowered ride height, I knew I'd have to cut the tunnel and rebuild it. When I did the hemi swap, I cut the tunnel out, shimmed the trans and rebuilt the tunnel. I want to say I have a 3/4"-1" shim on the mount. Talk about way off! I can do well over 100mph now with no driveline vibration. Note, I don't think the too low trans mount would be a problem for guys running super stock springs with the *** end up in the air.

Until I started the T56 swap, I didn’t realized how much the u-joint angles was a part of this process. It’s been a real eye opener for me. And it isn’t just what angle the motor is at, like you said with the SS springs, the attitude of the car has a huge influence.

Funny thing is, for me to say my motor is at 3 degrees is kind of pointless since that is measured relative to the ground. I need to take an angle measurement on the bottom of the front frame horn where it ties into the TB crossmember. Not certain that is very consistent, but it’s the only place I can find that isn’t sloped. Maybe it would be a useful reference for other people.

I too have heard that the Keisler TKO kits put the tail down to make it fit the A-Body but wouldn’t have guessed you would need 3/4-1” to get it right. That’s a bunch.
 
I think if you level car with bottom of rockers that would work. I used RV Jack Stands to level mine when I replaced floor.
 
Until I started the T56 swap, I didn’t realized how much the u-joint angles was a part of this process. It’s been a real eye opener for me. And it isn’t just what angle the motor is at, like you said with the SS springs, the attitude of the car has a huge influence.

Funny thing is, for me to say my motor is at 3 degrees is kind of pointless since that is measured relative to the ground. I need to take an angle measurement on the bottom of the front frame horn where it ties into the TB crossmember. Not certain that is very consistent, but it’s the only place I can find that isn’t sloped. Maybe it would be a useful reference for other people.

I too have heard that the Keisler TKO kits put the tail down to make it fit the A-Body but wouldn’t have guessed you would need 3/4-1” to get it right. That’s a bunch.
It doesn’t matter if the car is level. Just measure the engine, driveshaft and diff. Level ground is irrelevant since you are measuring the differences between the 3 angles. TREMEC has an app for measuring. It’s very helpful.
 
It doesn’t matter if the car is level. Just measure the engine, driveshaft and diff. Level ground is irrelevant since you are measuring the differences between the 3 angles. TREMEC has an app for measuring. It’s very helpful.

Yep. I just mean that my "3 degrees" reference is useless to anyone else unless they have the same stance.

The tricky part for me is I don't even have the bellhousing in, let alone the trans, so getting a driveshaft angle is...tricky. :)
 
I ended up just cutting the perches on my rear end and aligning it to my trans to make it all work when I did my T56 swap. Though I got to do that job twice due to a oopsie. When I first built my trans crossmember, I had left the transmission on a floor jack overnight and didn't realize it had sagged when I went to make the templates the next day. It sat so low that it ran my fuel rails into the firewall and eventually caused a fitting to leak (plus it hit about every rock in the road along the way). Regardless, at this point I had cut the perches on the rear axle and rotated it to match the powertrain angle. Once I figured out my mount was all sorts of off, I jacked it all back up, remade the crossmember, and cut the perches once again to roll the axle to match. Never cared what the actual angle was because I was just trying to get it tight to the floor to give me good clearance.
 
Never cared what the actual angle was because I was just trying to get it tight to the floor to give me good clearance.

One of my slow downs has been that I fixated on the motor angle way too much. Since I am cutting the floor and crossmember out and building my own, I am pretty free and don't have to worry about getting it tight to the floor. So I felt like I could shoot for the "optimal" angle, whatever that is. The instructions for the Mopar crate motor kits says the motor sits at 2 degree in a Challenger, so that's where I started. But 2 degrees relative to what? If it was to the ground, my chassis probably isn't at the same rake. If it is to something on the chassis, then what do I reference it to on my chassis? And thus the swirling water in the drain swept over my head and I wasted way too much time trying to just get a breath.

In the end, it finally dawned on me that the optimal angle is the one that fits the u-joints.

I would like to put this together with the rear axle that is in the car and not have to build a new one or fix the pinion angle on the one I have as part of the swap. There are plans for a trick 8.8 later on, but that's for when I start looking at ABS and 18" wheels. The first drive will be on a more stock chassis and I don't want to have to mess with the rear axle to do that. In the end, my 3 degree setup should (in theory) mean the u-joints are happy even if the pinion angle is lower than I read it should be.

I still don't understand why my pinion is low either. seems like it is way off what it should be and the axle is factory stock, just an A-Body 8.25 on stock (but good) 6 leaf spring pack. The car really isn't even lowered in the rear from stock. But the front is lowered a fair amount, maybe that's the difference?
 
So one advantage to having the motor up 3/4" or so is the steering clears the pan by a decent amount.

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I looked at how much clearance there is to drop the motor out of curiosity and it looks like the headers would crash with the manual box, the oil filter adapter would maybe just clear the k-frame and the oil pan doesn't have clearance to bring the motor down the full 3/4". In addition, the bottom of the oil pan is already 1/2" or so below the k-frame so that would be pretty low (IMO) if I dropped the motor.

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All of this was more just to look at it, I'm not entertaining the idea of trying to set the motor down. I don't like the idea of putting weight higher in the car, but since I'm not looking for 10/10th's I am going to chock it up to "it makes the motor fit better" and get on with the swap.
 
I believe Dodge offsets engines left and right from the rear end as well, which gives you the necessary difference to keep the u-joint bearings spinning and the needles happy. That's often one of the main things to look for regarding driveline angle. I used to deal with it a fair amount on industrial trucks. That was a little more important because of the torque you could put through them. Generally speaking I'd probably still try to keep fairly shallow angles as even though it might be "okay" if you had something like 5 degrees on either side, I think it's still going to stress them more than they need to be.

I think my setup is probably somewhere around that 1.5-3 deg number, but it's been a long time since I looked. A lot of it just came down to clearances like you're seeing. My headers are super close to my steering box and stuff like that, but they still clear. I do have some rear end noise, but I don't think it's really driveline related (anymore at least, maybe when I had my first botched angle install). It's odd though because it only really makes noise in 5th gear around 55-60 mph. Put it in 4th and it mostly goes away. Put it in 6th and there is still some, but not as bad. So it seems more like an overdrive thing than a pure rear end gear setup problem, but it's not been worth it to me to tear it apart to mess with. I set the gears up as best I could myself and they tend to say once they have worn in you're kind of stuck with it regardless.
 
I ran into the same questions and delima, twice with the Dart.. once with Hoopty. It's just really hard to make any decision, without the trans bolted up to where you can raise and lower it.

With Hoop, I didn't want to "C" notch one of the bed crossmembers and put it as high as it would go, without doing that. Probaby 5 degrees down. It worked fine but I really didn't care for the look of it. The drivetrain is very visible. So, earlier this year, I dropped the trans and just did it. Looks much better.

The Dart was a little different because I was also doing the 8.8 at the same time as doing the 6.4/904. I let the trans sit in it's stock position, regardless of angle. The angles were meh, ok. I found that at about 70, I had a slight vibration.. Added a little more pinion angle down with shims and it's smooth as silk now. Well, it was. Now with the 8hp going in, it changes a few things. Leaf springs are harder math for me and not typical with some calculators. My driveshaft guy says that if my trans is 3 degrees down, my pinion should also be 1-3 down..

But when referencing "angle to what??" it pretty much comes down to whatever you decide. I mean, I think I'm at 3.5 right now.. but that's by using "my reference point". May not be the same as yours, or his or whoever. I have a digital angle meter that I can zero out. I have one spot on the car that I use as zero. So know matter what angle the car is at, I zero on that point and then the angles always read as they did before moving the car. Once the car is on the ground and the suspension has settled back in, that might be 2 degrees with level earth.. who knows. But as it is now, my trans pans is almost level with the frame.. looks more ntural that way.

btw, I saw a guy on fb with almost the same build as yours.. same headers, 6 speed etc. You may have seen it.. Beau Henderson in G3 Hemi Swapped A Body Mopars. Not sure how I feel about the tunnel, but he's making good progress
 
My tunnel is horribly ugly, so I'm glad it's covered in paint and carpet, lol. I basically just rounded a flat piece of sheet metal I got from a guy at work over my leg into something that looked roughly like a section of a cone. I don't have metal fab skills like that or the equipment to do it real nice, so I just made it work with what I had. Seems to at least have held up fine after nearly 10 years or something though.
 
btw, I saw a guy on fb with almost the same build as yours.. same headers, 6 speed etc. You may have seen it.. Beau Henderson in G3 Hemi Swapped A Body Mopars. Not sure how I feel about the tunnel, but he's making good progress

I've seen his posts. I agree on the tunnel, but he is making progress and I'm not so I can't point fingers.

I went out to the garage yesterday with the expectation that I was going to have the tunnel opened up and the crossmember removed before the day was over. Couldn't wait to see the trans up in the car instead of sitting off to the side. Instead I spent all my time removing undercoating so I didn't have to deal with it when the sheetmetal is all floppy.

My plan is to split the tunnel down the middle and make cross cuts so I can just open the tunnel instead of remove it entirely and build an entirely new one. Imagine the turkey from National Lampoon Christmas Vacation movie.

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That's what @72bluNblu did and it makes some sense to me, plus I don't have to weld the driver's side patch back in like he did since I am starting with an automatic car rather than a 4 speed converted car.

Now I am trying to figure out how to create a cardboard sketch of the profile of the trans when looking down on it so I can get a better idea of how far down to cut the tunnel. Will my insanity never stop??
 
My tunnel is horribly ugly, so I'm glad it's covered in paint and carpet, lol. I basically just rounded a flat piece of sheet metal I got from a guy at work over my leg into something that looked roughly like a section of a cone. I don't have metal fab skills like that or the equipment to do it real nice, so I just made it work with what I had. Seems to at least have held up fine after nearly 10 years or something though.

Something to be said for getting it done. Perfect is the enemy of progress?? Or something like that.

I did get the floor cut enough that I could get the bell bolted up. So some progress.

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My tunnel is horribly ugly, so I'm glad it's covered in paint and carpet, lol. I basically just rounded a flat piece of sheet metal I got from a guy at work over my leg into something that looked roughly like a section of a cone. I don't have metal fab skills like that or the equipment to do it real nice, so I just made it work with what I had. Seems to at least have held up fine after nearly 10 years or something though.

I've seen his posts. I agree on the tunnel, but he is making progress and I'm not so I can't point fingers.

I went out to the garage yesterday with the expectation that I was going to have the tunnel opened up and the crossmember removed before the day was over. Couldn't wait to see the trans up in the car instead of sitting off to the side. Instead I spent all my time removing undercoating so I didn't have to deal with it when the sheetmetal is all floppy.

My plan is to split the tunnel down the middle and make cross cuts so I can just open the tunnel instead of remove it entirely and build an entirely new one. Imagine the turkey from National Lampoon Christmas Vacation movie.

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That's what @72bluNblu did and it makes some sense to me, plus I don't have to weld the driver's side patch back in like he did since I am starting with an automatic car rather than a 4 speed converted car.

Now I am trying to figure out how to create a cardboard sketch of the profile of the trans when looking down on it so I can get a better idea of how far down to cut the tunnel. Will my insanity never stop??
I blindly cut mine out.. Kinda. I figured I had to start somewhere. If it needed more, I'd cut more. I just like a nice rounded tunnel, no bigger than it needs to be with a smooth transition. There's a guy on fb that has shared the "split" tunnel and honestly, I just couldnt make myself do it and feel good about it. I'll share a Pic of his. It was alot easier (for me) to just start with a clean slate. Also pictured is a picture of my sheet metal rollers

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I blindly cut mine out.. Kinda. I figured I had to start somewhere. If it needed more, I'd cut more. I just like a nice rounded tunnel, no bigger than it needs to be with a smooth transition. There's a guy on fb that has shared the "split" tunnel and honestly, I just couldnt make myself do it and feel good about it. I'll share a Pic of his. It was alot easier (for me) to just start with a clean slate. Also pictured is a picture of my sheet metal rollers

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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.

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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.
 
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.

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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're probably going to run a console, right?

Look at us car tool.. They sell the tunnel you probably need

Edit.. Just looked. Holy **** they are pricey!
 
I think the auto has an "advantage" of being a little smoother and less fore and aft space required to install it, so you can fit the tunnel a little tighter. It might be a bigger tunnel in some regards, but with my T56 I needed to leave enough room to be able to stick an input shaft in there and push it forward several inches. You can shoot it in at an angle for a little bit, but ultimately you still need probably at least a good 3" or more that you can pull it straight back to clear the clutch. With an auto I think you only have to be able to pull it back maybe 1-2", if even that. Just one thing to keep in mind when building a tunnel. Don't build it so tight you can't take things back out after you're done. Would be a pain to hug everything tight, get it all tacked together, then you can't pull the trans to do the bottom side cleanup.
 
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You're probably going to run a console, right?

Probably, but that topic hasn't been on the radar yet. I could see it being just carpet like in my '74 but long ways to go before I decide.

I didn't figure a bench would fit with the T56 but the guy on FB (Beau) is making me wonder.

Look at us car tool.. They sell the tunnel you probably need

Edit.. Just looked. Holy **** they are pricey!

Yep, I saw them awhile ago and they are nice. But $900 nice?? Out of my price range even if is worth it.
 
I think the auto has an "advantage" of being a little smoother and less fore and aft space required to install it, so you can fit the tunnel a little tighter. It might be a bigger tunnel in some regards, but with my T56 I needed to leave enough room to be able to stick and input shaft in there and push it forward several inches. You can shoot it in at an angle for a little bit, but ultimately you still need probably at least a good 3" or more that you can pull it straight back to clear the clutch. With an auto I think you only have to be able to pull it back maybe 1-2", if even that. Just one thing to keep in mind when building a tunnel. Don't build it so tight you can't take things back out after you're done. Would be a pain to hug everything tight, get it all tacked together, then you can't pull the trans to do the bottom side cleanup.

Yep, that's on my radar. Part of why I want a cardboard cutout of the trans so I can "play" with it easily. There is even an odd tab on the DS of the trans that @72bluNblu cut off for that very reason. I am looking at either building my crossmember to clear that or cut it off like Blu did.

BTW, it isn't on the older T56's, only the T56 Magnums that are OEM TR6060 based. I believe the OEM's used it to attach wiring harnesses to.
 
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