Datsun Roadster: 2020 Challenge Build

Let's do a quick catch-up on hours. As of loading for last challenge, I was at 627.

Ive spent about 10 disassembling the trans and getting these axles and mocking stuff up, so let's say we're at 637 hours invested.

In case anyone was as confused as me... the Cobalt doesn't use an intermediate shaft on one of the CV axles, like most FWD transmissions. The transmission takes that space instead. Strange design, but should work great for Robbie!

In reply to maschinenbau :

Huh? No it definitely does, it's just that the CV axle pulls out of the intermediate shaft on the passenger side but still splines into the diff. 

The removed intermediate shaft is shown in front of the diff in my photo.

Oh cool, today I learned...

It does look like the pedestrian cobalts use that weird wide trans... Which I didn't know about before. 

I will say it is really lucky for me that the jackshaft uses the same splines as the CV axle, and therefore it is easy to simply remove from the drive line. But I also know GM, and having one part number for CV axles instead of a left and a right probably saved them elenvty bajillion dollars or something.

Copied from the PRI thread. 

For reasons

In reply to Robbie (Forum Supporter) :

I would have to say that yours is more "radical."

In reply to hobiercr :

Well, thank you!

I'm still going to steal some ideas

In reply to Robbie (Forum Supporter) :

Did you manage to sneak into PRI?

Are these Datsun door hinges?

Being repurposed into lower shock mounts?

AND upper shock mounts?

On BOTH sides?

Yes, yes, yes, YES!

Ladies and (mostly) gentlemen, we have real front springs and shocks!

This project was a bit like harvesting a buffalo where you need to find a use for everything. One rear shock came with the donor cbr, and another came in a trade deal I made about 2 years ago. The door hinges as previously mentioned made for excellent shock mounts, the "risers" on the upper ends were made from the pullrod mounts we cut out of the upper a arms, and the tube connecting the sides was made from the original Datsun steering column. 

Oh damn.  No more bouncy bouncy on track! Giggity!

So I can't lie, I had a 'little' help yesterday. Big shout-out to Gumby and Nocones for spending their Saturday and sprinkling their magic on FDat. 

We did a lot of eyeball engineering, but now the front of the car is suspended on real springs and dampers. Even better, I think we have a good plan for the rear!

Edit: 665 hours.

Springy sprongy, dampy damping

The Bad Decision Triangle was very small yesterday.

Very nice!

hobiercr said:

The Bad Decision Triangle was very small yesterday.

You know what that means.....

In reply to gumby :

Point singularity.  Either we all no longer exist or one of the BDT members bought a new project.  

..  .  Oh crap.. 9 days until I post a new thread.

Today I repositioned the lower shock mount on the passenger side a bit. We originally eyeballed it about 1/2 inch closer to the upright than the driver side. But it was just tacked on so I cut it and moved it. 

I also did some analysis in vsusp (very cool tool btw) on the front suspension. Let's just say I don't think it was engineered to move. Now that it will be moving, the camber gain curves will matter. There also isn't a whole lot I can adjust to make it better, but one thing I can do is I can change the effective length of the upright by adding spacers above or below the rod ends. This moves the rod ends up or down on the upright. As it turns out, I can't make the suspension "great", but I can easily make it a whole lot better. 

Even distance from lower shock mount to upright:

​​​​​

Then I had to finish the "compression link" at the top of the shock mounts. I can't weld this in because then the upper a arms would be trapped with no way to disassemble. So it has to bolt in. 

Therefore, I grabbed my hole saws and some cool leftover motorcycle chrome bolts and some 1/8 scrap plate. 

Then I welded those onto the ends of my Datsun stock steering column tube, voila!

Added about 3 hours today bringing our total to 668.

This is gonna be so damn awesome when you're done.  I berkeleying CAN'T WAIT.

If you wanna get rid of those washers on the struts I can turn something for you, I've got enough scrap that I've picked up for free.  Just need dimensions.

In reply to Mr_Asa :

Oh, nice! Yes the washers are just for mockup but they would work in a pinch. The shock needs to be spaced rearward because of interference issues with the upper a arms. 

I'll get a good napkin drawing for you tomorrow.

Sounds good.  I'll dig through my scrap bin and figure out what I have that is free to budget.

This thing just keeps getting radder, and radder!

Mr_Asa said:

Sounds good.  I'll dig through my scrap bin and figure out what I have that is free to budget.

I think I've got enough scrap for spacers.