Well, since someone recently asked for my old "write up", and other apparently hadnt seen it, I thought I would try and post an actual write up since my last was just showing off my build.
First things first. You will need to make the front lower bolts go through the block, into the tranny, rather than through the tranny into the block. So you will have to grind down the block on the front, and drill the holes through. This was the bolts can go through, as well as the heads sit semi-flat. So you will have the 3 lower bolts go through the block side, into the tranny. Just like the rear does from the factory, now the front two will as well. And the top 2 bolts will go through like stock. The rear most will bolt up without modification, and the front upper will need to be slightly hogged out.
Compare that picture to this Y7 block. You can see on the left, where it has been ground down. On both front lower holes. There is a lot more grinding to do on the bottom hole.
Next, you will need to modify the bell housing of the transmission, to accept the bolts/thread.
This is a Y1 tranny, and I used a YS1 tranny. But it gives you an idea of the voids that I had to weld.
This rear triangular hole will be where the rear bolt goes into. I had a buddy cut a piece of 1/2" thick aluminum on his mill at work.
I also had the front two holes welded, as well as adding a little material to the inside part of the flange/bellhousing, since the bolt will go towards the inner diameter.
As you can see, everything was ground flat/smooth after welding.
After that, we lined the block and tranny together, to mark where the holes need to be drilled. The rear top hole will bolt up without modification (the one closest to the t-stat housing), with the input shaft through the clutch/flywheel. The top front hole on the tranny will need to be oblonged, or hogged out slightly. Once you start putting it together, you will see how the hole is just BARELY off.
You can see in the pic above, I drilled and tapped the holes. If you notice, I accidentally put the front lower bolt in the wrong hole. You can see the welded area above where the bolt is. Thats where it should be obviously.
And this piece wasnt necessary, but we welded a tab on, near the starter. This is for the T-bracket to bolt onto, since it would normally bolt on the B series block. We also put a metal spacer inside of the T-bracket, to keep it solid.
Now, for the clutch/flywheel, there are multiple options available. You can either buy a Competition Clutch flywheel that is a B series flywheel with D series bolt pattern, and then be able to use a stock B starter, and any B clutch, or you can buy a Competition Clutch twin disc that is the same thing. Or you can use a D series flywheel, and modify the starter, as well as buy a modified clutch.
I went with the latter. I used a D16 flywheel, which obviously takes a D16 pressure plate. So I needed a D16 clutch disc. But the clutch disc needed to be a B series spline (I had a YS1 92-93, same as hydro, so big spline). I called a few companies, the eBay XTD company wouldnt do it, LSD wouldnt do it, but Action and Competition would. Competition did it for the same price as their off the shelf disc. I paid 117 shipped to my door. It was just a D16 disc with a B18 hub pressed in.
And not all trannies are the same. But when I went to put the tranny up to the assembled block, it was hitting the t-stat housing/bolt. So I notched the tranny slightly. Ive seen a few more that did this, and some that didnt need it.
With everything bolted together, we were able to modify the halfshaft.
We slid the halfshaft in, and had to weld tabs onto the halfshaft. We also had to grind down on part of the original shaftshaft, to clear the alternator bracket. I noticed that the hydro halfshaft (what I used) needed less grinding than the cable. Also, there are a few alternator brackets out there. There is one that is more of a thin metal strap, than a large cast bracket. That one was easier for me to work with. I believe its off of a D16A6.
You can see the bottom left hole that we didnt use, is cut. That was all it took for the hydro shaft to clear the thin alternator bracket. If you have cable, or the heavy alternator bracket, its going to take a lot more "massaging"
Now onto the starter. Im going to tell you right now. If I hadnt had a friend do this before me, I may have given up and bought a Competition Clutch D2B flywheel, just to save me the headache. But in case youre going to go through with it, here is how I modified my starter.
First off, no picture, but I drilled and tapped the hole on the tranny. You know the lower rear hole you normally have a SUPER long bolt go into the block? Well rather than weld and tap a new hole on the block like SpeedFactory, we here in Colorado like to make shit simple. The hole is the perfect size for the tap. Just run a M12x1.25 tap (17mm Honda bolt, same as the tranny/block bolts) through it, and find a short bolt to use. Now your starter can just stay on the tranny. And obviously, you need to open the hole up on the starter, so the bigger bolt can go through it now.
Next, I ruined a few starters figuring this all out. And I had instruction prior. LOL. I had to grind down the housing, so that the starter can pivot. No during pics, but I do have after for you to compare. Pretty much, you will need to space your starter off of the tranny by 3/16". I found 1/16" more wasnt going to hurt, and it didnt. So I bought a strap of 1/4"x1"x however long strap. So I could cut the tabs from it, and have 1/4" thick spacers to weld onto the starter.
Now, with that 1/4" thick spacer in mind, you can get an idea for how much of the starter needs to be ground off. You pretty much need to grind all the way around the snout, so it can turn down, or inwards, since youre putting it on a smaller diameter flywheel.
You will also need to open up the front/upper tab, so that it can turn down. And then you weld the spacer on accordingly, to provide a new hole/alignment, once you find that alignment.
I also found that there are at least 3 different B series starters. None of them have similar internals. So find your most common starter, and modify that one. That way, when it goes, you can find another and swap internals, rather than modifying another starter. Because its a huge bitch.
Here is my finished product
The tab/ear I opened up to realign how the starter sat.
The hole that I opened up for a bigger bolt.
Now onto getting it into the car. Each chassis will be slightly different, but very similar. You must use a set of B series motor mounts. You use the tranny mounts only. Now, the B series is about an inch longer of a block. So your B series tranny/mounts will sit your D16 motor about an inch closer to the passenger side. So you will either need to make a mount for your driver side/timing belt side motor mount, or you can space the mount off of the block by an inch. I also found that the Z6 sits funny as fuck in an 88-91 chassis. So the driver's side mount is tweaked as hell. But if you made your own, itd be a lot easier.
The way I spaced my mount off of the block, was to use a spacer between the L-bracket part of the mount, and the block itself. Then just cut the timing covers slightly. Everyone of my friends that has done this needed an inch. For some reason I only needed 3/8". So I just took an extra L-bracket, and I cut it down to the flange that bolts to the motor. Then I had it milled by my friend again, so it was flat. I then just used longer bolts.
I also had some motor rocking issues with only 3 mounts. So my friend NayrOne at Colorado Race Fab made me a gangster ass front mount.
And while I was there, we welded the drain plug on the block up. If youre not making over 500-600whp, and have no plans of doing so, you dont need to do this. But you also probably dont need a B series tranny. So stop being a bitch, and turn the boost up!
D2B FTW bitches
And not one tranny issue the whole fucking time.
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Topic: theidealone's D2B Write Up (Read 17492 times)