PhoCup's 408 Exo Build

[phocup]

Hmm .. Keith from FM pretty much told me to go rubber bushing unless its a track only car that's going to live life on the trailer. Seeing how adamant he was, I went with rubber bushing. Hope that goes in as easy.

Also, it was quite an adventure today .. but finally ..



Glad I didn't have it shipped already powder coated though .. high chance it would have been damaged.



I also found out there's another Exo lover in the family .. though for different reasons.  Exomotive gymboree set anyone ?

[phocup]

Dropped of the frame at the powder coater .. 

Then inspected the bodywork .. and found some dimples.      
Known issue or just lucky me ?

[phocup]

Guessing from the lack of reply no one else is having my dimple issues ?    

On the bright side, I did get more stuff done.  Pedals are half assembled.   Hope the skate board grip tape can take the abuse.   The good thing is they're dirt cheap so worse case I'll slap on some new ones.   Need some gas pedal extension though.
 
  

Also got my bushing pressed in.  This job is really more of an art than a science IMO.   Pretty much no way to get all the bushings in EXACTLY the same on both side.   Spent already A LOT of time tweaking / ect but in the end things are still slightly off.  1/10th here.  1/10th there.  I'm just glad I'm not that OCD, so I wont need to spend another 4-5 hours tweaking.   Its good enough .. hopefully.      Tomorrow they go on the sub frame.   



I'll add that its a pain in the butt to work with freshly powdercoated / painted stuff.   Its so pretty, I end up spending a bunch of time coddling it and treating it like a new born baby.   Worse part is I STILL ended up with some small nicks / scratches.      

[calibuild]

Sept 23, 2016 22:12:28 GMT phocup said:

Dropped of the frame at the powder coater .. 

Then inspected the bodywork .. and found some dimples.      
Known issue or just lucky me ?


Re: Bodywork question, you are correct. The fiberglass is 'non-finished' which means there will be some imperfections. When I unpacked mine the gas tank had a crack which was more than just a cosmetic imperfection, so the supplier is fixing that.

[phocup]

Thanks.  I didn't know the fiberglass was considered 'non finished'.   I'll stop worry too much about it and order some sticker / vinyls.  

Moving on, I'm a bit embarrassed to admit to having another Tim Taylor moment today ..



Went to press in my diff bushing today.   Was rushing a bit because was running a bit late to pick up my daughter from school and had a buddy over helping hold the diff in place so wanted to just get it done.   That's mistake #1.

Mistake #2 was not noticing that the center steel tube would be extended BEYOND the 'bottom' of the diff arm when pressed in, so my initial setup was pressing the bushing down into a flat steel surface using another flat steel surface.



Mistake #3 was trying to Tim Taylor it with the entire 20 ton of pressure when I saw that the bushing wasn't going in further vs taking it out and inspecting the problem.   

The end result .. mangled mounts.

However, I learned my lesson, setup the press slightly different to make room for that tube and the second mount went in without issue.

Here's the difference.



Pressing ain't easy.    

So now I MIGHT have lucked out because it does fit pretty well into the subframe.  The bolt hole was not deformed THAT bad so I didn't have to force it at all to get it into the sub frame bolts.   It just slid in like its supposed to.



However, putting the mount plates on, its not sitting flush even on the 'good' side.   There's a substantial gap.



Of course this is with the diff / subframe upside down, so when I flip it over, gravity will bring the diff DOWN to meet the mount.   However, there will be plenty of 'play' in there.  The diff will be able to move up / down quite a bit ( 1/2" ? ) on that bolt if enough force is applied directly upward.  

So I have two questions:

1.  Do you think I need to replace that bushing or is it likely to be okay as is ?   Its the Mazdaspeed 40% firmer rubber one so its about $75 bucks to replace now.

2.  Is that 'play' there by design or did I f' even more things up than I realized ?

[Fin]

Oct 4, 2016 5:23:22 GMT phocup said:

1.  Do you think I need to replace that bushing or is it likely to be okay as is ?   Its the Mazdaspeed 40% firmer rubber one so its about $75 bucks to replace now.

2.  Is that 'play' there by design or did I f' even more things up than I realized ?

Interested to see the answers as this is exactly what had me scratching my head yesterday as I re-attached the diff. I've replaced all the other bushes, but held off on this one as it seemed OK.

[gwnwar]

Bit the bullet replace it.. As is it might through the alignment off a little..and center spacer might be torn off the rubber inside were you can't see it.. Replacing it now will be easier then later. There is suppose to be a gap on bottom side for movement/flex..

[phocup]

Bullet bit. New parts ordered. Thnx gwnwar.

Confirmed here also by Keith that "The bushings do have a fair bit of play in them in the vertical direction - lifting the car with a jack under the pumpkin will make it move up."

Strange IMO that the design allow for so much play in the drive line, but I'm not an engineer so will resist the urge to 'pad' to tighten up the play.

[Fin]

I've seen the torque setting as 68 foot pounds for the centre nut and 17 for the two outers

[phocup]

Got the diff bushing replaced yesterday thanks to GoodWin's quick shipping.    This time it only took me 15 minutes to get the old bushing out and another 10 min to get the new one in without making any stupid mistakes.  *pat self on back* ..

Also .. guess this means I'm chassis #215 in the US ?

[phocup]

Staring at the spaghetti monster on the floor tonight .. I think this was the first time during this project where I thought .. WTF did I get myself into.

[SeanW]

Oct 15, 2016 8:27:52 GMT phocup said:

Staring at the spaghetti monster on the floor tonight .. I think this was the first time during this project where I thought .. WTF did I get myself into.

That's not looking too bad. Looks like you've got everything labeled which is a HUGE help. Honestly, the wiring harness was the most intimidating aspect of the build for me, the thing I dreaded the most. Turns out that it's really not all that bad, just super tedious and time consuming. All of the mechanical stuff just flies together, the electrical is very fiddly.

I highly recommend that you buy a really good crimping tool, heat gun, and weather proof heat-shrink. Heat shrink butt spices are handy, too.

Also, always willing to lend a hand here.

[phocup]

Thanks for the offer Sean. I've been reviewing yours and Steadfast's build as well as a few others today to prep myself as much as possible.

Quick question though. I did notice that there was a lot of ground connectors. Some of those are next to stuff that will be deleted ( like airbag ). Do I need to reinstall every single ground ?

[SeanW]

Oct 16, 2016 5:44:45 GMT phocup said:

Thanks for the offer Sean. I've been reviewing yours and Steadfast's build as well as a few others today to prep myself as much as possible.

Quick question though. I did notice that there was a lot of ground connectors. Some of those are next to stuff that will be deleted ( like airbag ). Do I need to reinstall every single ground ?

Not really. Once you start to pair down the harness you'll find circuits where you can delete the ground or relocate the ground to a more sane location. (Some of the wiring runs in the stock harness are mind boggling.) Though I installed it as a temporary thing, I've become a fan of the grounding bus bar I put in my wiring tray. It has made knowing that circuits have really good grounds very easy with fewer holes drilled in the chassis for grounding points. I'm keeping it as a feature of my build.

[gwnwar]

Ground wires or lack of seems like the biggest problem in trouble shooting.. If you can leave all of them along till the end.. There are 11 ground points on the '97.. If you haven't all ready check out www.mellens.net/mazda/Mazda-Miata-1997/wiring.pdf
There is 1 page (Fig.13 Grounds) that shows what go to each.. You might want to print off each page of wire runs put in plastic sleeve so you can have them on hand.