CD009 Bellhousing build thread Warning lots O pics

[Derek]

Ever since I was a small boy I dreamed of having a 6 speed transmission in my Z car.

 

Ok it was actually in 2014 when I heard that people were retrofitting the CD009 into various different vehicles and thought that would be awesome.  At the time I was up to my ears in KN20 development and I put it aside immediately.  Fast forward to a few months ago and I decided to finally bite off doing my own system. The Hoke system is a great piece of engineering but it wasn’t what I wanted. JWT offered a conversion plate but you needed to source a used bell housing and like the Hoke adapter required a special flywheel. The solution for me was always going to be a cast bell housing.  My goals were to be able to use my existing clutch, pressure plate and flywheel. I contacted Chris at at Godzilla Raceworks too get his input on the feasibility of my approach.   I know a lot about castings but my knowledge of what components play nice with other components is seriously lacking. Based on the info Chris provided  I decided to move forward.

 

Step one. Jump in with both feet by buying a brand new CD00A from Z1 Motorsports.

 

 

 

Step two. Cut the bell housing off of a brand new transmission so there was no turning back.

 

 

The first thing I needed to determine was can I get 100% spline engagement on the clutch disk. I setup a block, crank and flywheel on the bench. I removed the pilot bearing. I then slid the transmission into the crank until the pilot shaft bottomed out. I pulled it back 6MM and made a reference mark on the bench. Visually the pilot shaft looked like it would play nice with the pilot bearing so I moved on to the next step. Check spline engagement.

 

 

 

 

I bolted an old PP and disk on and slid the transmission back into place. I had over 100% engagement and it looked like some version of the longer release collar would bridge the gap.

 

 

 

So now that I was confident the math would work I had to work out how I was going to machine the casting. The big problem for me is my CNC mills are converted Knee mills and they don’t have a lot of Y axis travel. I also don’t like doing uber precision work in a production environment. I decided early on that I was going to leverage the existing front cover to be the “glue” between the transmission and my bell housing. My plan was to sandwich the front cover between the bell housing and transmission.

 

 

  After confirming that I had a decent machining strategy it was time to collect data.  I scanned an old 5 speed case I had.

 

 

 

 

This is what I refer to as a dirty scan. It’s only for me to design around. I import the mesh into my solid modeler and it becomes a reference for the features I want to add. All of the critical  measurements are done with a touch probe in the mill or conventional calipers and micrometers.

 

 

 

 

 

First step was to align the mesh with the bell housing holes I acquired with the touch probe. I also pulled the input bearing hole from the case when I got the bolt pattern.

 

 

 

 

 

I then then positioned the scan and the probe data I made of the CD009 cover centering the input with the input from the case.

 

 

 

 

 

 

And then I push a couple of keys and suddenly like magic a bell housing casting model appears.

 

 

 

 

 

 

Ok there is a lot more to it than that but you get the gist.

 

Next I had to design the machining fixtures. All of the important stuff is done in the first setup. This ensures the input shaft of the transmission lines up with the pilot bearing in the crank.

 

 

 

Pattern time. Without getting into a ton of detail here is the finished tooling just before I shipped it to the foundry.

 

 

 

So while I waited for the castings I worked on all of the fixturing.  By using the existing front cover I was able to save a ton of precision machining. But the cover has to be positioned properly. I accomplished this by making a fixture that indexed the cover on the input bearing. I then bring all of the bolt face bosses to the same level and then ream 3 of the bolt holes to accept a 10mm hollow dowel.

 

 

Here is the finished cover with the dowels installed.

 

 

So I guess I was in a hurry on the machining since I didn’t get any process shots. Here is a shot of the first test after machining the engine flange.

 

 

 

 

This is testing the cover fit.

 

 

 

 

 

This is before the clutch lever and slave work.

 

 

 

And the finished product.

 

 

 

 

 

 

I designed the cross member to be as versatile  and adjustable as I could. I also decided to share the load between the floor/frame and tunnel. On most of our cars the tunnel is probably one of the most unmolested rust free parts of the car.

 

 

 

 

 

 

It uses the crossmember from a 72 and up and an Energy Suspension transmission mount.

Both ears are adjustable up and down and the ears are slotted so the cross member is adjustable side to side. You can remove the transmission just by removing the ears. The floor/tunnel bars stay in place.

 

 

 

Here is a slightly fuzzy shot from underneath.

 

 

 

And the finished product.

 

 

 

 

 

What’s next?

Now that I have a running car I’m finishing off a second bell housing and cross member and sending it out to Chris at Godzilla. He is going to test fit it in a 280Z and check the fit of the cross member as well as the clearance on some headers.  Godzilla Raceworks is going to be a dealer for these and he took care of having the drive shaft made. As soon as we verify the fit on his test vehicle I’m going to go into production.  I’m not taking pre orders but if you want to be on the list of pioneers you can contact me or Chris at Godzilla.  When the bell housings are done you will have the first option to purchase.

 

Pricing:

 

Bell housing.  $900.00

Crossmember.  $295.00

 

Labor charge for modifying front cover. $75.00

You must supply either a brand new cover or brand new take off as a core. No used covers will be accepted.

 

So far I’m really liking the gear spread on the 6 speed. I currently have a Subaru 3.9. I’m going to put the stock 3.364 diff back in to see if it brings the revs down at 75mph and see how it effects the first and second gear feel. For me that is the most important thing.

 

Thanks

Derek

[calZ]

Fantastic work as always, Derek. 

[rturbo 930]

Impressive as always. Good to see your car is up and running again too, as last I recall you had some kind of failure that took it off the road. 

[blairjj]

Derek.... shut up and take ALL of my money!

[seattlejester]

...I think I love you...

[DREW RBZ]

Wow...that is amazing!  

[Ben280]

If I didn't just do the Jerico swap in my car, I'd be rubbing my pennies together to make this swap happen!! 

 

Amazing work, love this solution. +1 for Godzilla Raceworks putting together a full kit.

[clarkspeed]

You ARE the man!

[Ryanotown22]

Does the driveshaft work without any modifications? 

[Ben280]

1 hour ago, Ryanotown22 said:

Does the driveshaft work without any modifications? 

 

Sounds like Godzilla will be selling a custom driveshaft. Can't imagine that a stocker off the shelf will work with this arrangement. 

[ozconnection]

Just paid for the bellhousing BUT.....how does the rest of the gearbox attach to the cast bellhousing...I didn't catch that bit.

[Derek]

Thanks for all the kind words and what I think is a marriage proposal from Seattlejester. I love you too but you still have to pay full price for a KN20. Nice try though.

 

On 8/19/2020 at 7:37 AM, ozconnection said:

Just paid for the bellhousing BUT.....how does the rest of the gearbox attach to the cast bellhousing...I didn't catch that bit.

 

Crap I missed a picture when I did the post.

 

So I machine the bosses on the Nissan cover to the same level which keeps the bell housing parallel to the transmission. The three dowels keep the  bell housing centered on the input shaft. Longer M8 bolts sandwich the whole rig together.  If you look closely you can see the new boss for the clutch pivot so that it is on the correct side.  The internal ribbing probably is over kill but I thought it looked cool. Every conversion system other than Hokes that I know of uses these bolts as the mounting point. From what I can tell I'm the first to use the existing cover. as part of the system.  As part of the assembly procedure I recommend a dry fit with no clutch or pressure plate and the transmission in gear. Bolt the transmission to the motor with a pilot bearing installed. You should be able to turn the output shaft by hand if the input shaft is riding in the bearing properly. 

 

I'm confused by "just paid for the bell housing"  I haven't sold any yet.

 

Something else I missed was the fact you have to modify the tunnel just like every other CDXXX conversion.  I'm putting the finishing touches on the installation instructions and I'll post the PDF here so people can get an idea of what is involved.

 

Edit: Just talked to Chris at Godzilla. I'm no longer confused:)  Well I'm still confused but that is my general state of mind.

 

Edited August 20, 2020 by Derek

[Zetsaz]

This is beyond brilliant. I love it!

 

[DuffyMahoney]

23 hours ago, Derek said:

Thanks for all the kind words and what I think is a marriage proposal from Seattlejester. I love you too but you still have to pay full price for a KN20. Nice try though.

 

 

Crap I missed a picture when I did the post.

 

So I machine the bosses on the Nissan cover to the same level which keeps the bell housing parallel to the transmission. The three dowels keep the  bell housing centered on the input shaft. Longer M8 bolts sandwich the whole rig together.  If you look closely you can see the new boss for the clutch pivot so that it is on the correct side.  The internal ribbing probably is over kill but I thought it looked cool. Every conversion system other than Hokes that I know of uses these bolts as the mounting point. From what I can tell I'm the first to use the existing cover. as part of the system.  As part of the assembly procedure I recommend a dry fit with no clutch or pressure plate and the transmission in gear. Bolt the transmission to the motor with a pilot bearing installed. You should be able to turn the output shaft by hand if the input shaft is riding in the bearing properly. 

 

I'm confused by "just paid for the bell housing"  I haven't sold any yet.

 

Something else I missed was the fact you have to modify the tunnel just like every other CDXXX conversion.  I'm putting the finishing touches on the installation instructions and I'll post the PDF here so people can get an idea of what is involved.

 

 

 

I now need you to build me a 6 speed trans that will fit in my series 1 without modifications to the tunnel:)

[Derek]

1 hour ago, DuffyMahoney said:

I now need you to build me a 6 speed trans that will fit in my series 1 without modifications to the tunnel:)

 

Actually I'm glad I have to cut the tunnel. It's my way of flipping off the series one purists:)

 

I got a six speed and you don't na na na na naaa na. 

[seattlejester]

Dang saw right through it.

 

Just makes my future dream build much easier, one stop shop! Just need a rear end setup *cough cough*

 

I really like how you did it, I think the fault with mine was my unwillingness to push the engine forward from where I had it (touching the firewall) and thus pushing the transmission so far back requiring a shorter shifter etc.

 

Driveshaft needs to be bespoke since the input is very different and the 350z driveshaft is actually a carbon tube and thus not able to be shortened.

[Leon]

And this is what makes HybridZ great. Hell yeah Derek. 

[Derek]

1 hour ago, Leon said:

And this is what makes HybridZ great. Hell yeah Derek. 

 

I seriously don't think I would be doing this stuff if HybridZ didn't exist. It's really sad that people have taken to FB to find answers as opposed to going to forums. I read some stuff there and just shake my head at a lot of the answers.

 

Back to the CD009. Working great. CD009 transmissions are notorious for gear rattle in neutral with the clutch out and mine is no different but other than that functionally it's fine. I think for my driving desires the 3.9 is a tad too much. The revs are a little high in 6th. I think a 3.54 would be a better choice.  But the gear spread from 0-50 MPH is really a lot of fun in town.  I think I'm going to put my stock rear and axles back in to get a feel for that and see how it goes.  

[DuffyMahoney]

Facebook doesn't work, they stop people from being able to search, really it's a poor substitute.  

 

 

I would seriously look at the 3.7, happy medium?  I think they are a bit rare.  But might be awesome.

[Derek]

I know it's a long shot. Looking for a used input shaft for a CD009 6MT. The critical parts of the shaft are the pilot area and the front bearing. I need to make a QC test rig for the bell housing.