Datsun Roadster: 2020 Challenge Build

I may have bitten off more than I can chew on this one. Ooops.

We traded the AMC at the challenge for a wad of cash and a Datsun and a half. The rusty car (what I'm starting with) is "complete" and there is also a rust free body on the way. The rusty car is rough. And rusty. But there's gold in them there hills, and I need to find it.

Delivery of the Datsun and a half to my house was included as part of the deal, and that is a great bonus. Even though the deal was struck at the 2019 challenge, the first delivery wasn't able to happen until the week of Thanksgiving, and I was out of town. So really the first day I was able to get at the Datsun was yesterday.

I pushed it off the trailer with my father in law. Here's what were starting with:

Put it up on the lift to poke around a bit.

Frame (the part I need) mostly looks ok but there are a couple bad spots that should be fixable.

Then, like any sensible human, I decided to make one pile of junk into two piles of junk.

I really do love the simplicity of these cars. It took about 5 hours to get this far and most of that was dealing with the two rusty body mounts in the footwells.

Really the big issue was the steering shaft fouling on the carbs. I could have just removed the carbs. But have you seen how long my shaft is?

I also love how far back the engine sits behind the front wheels.

Based on the magnet test, this 3rd member seems to be made of aluminum - could that be?

Finally heres where we sit now. Next post to talk about goals, timelines, budgets, and other lame stuff for the beancounter types.

Refresh... refresh... refresh...

Finally!

Ok, let's talk about the challenge. 

Goal number 1. This is the most critical goal. This car needs to run and drive at the 2020 challenge. There are no excuses and no exceptions.

Goal number 2. Be relatively fast.

Other goals: flexible.

Current budget is that I've spent $750 on the Datsun and a half. Since there was a trade involved it's a little wishy washy but that was the advertised price so I'm using that as the budget starting point.

So, what's my direction? What engine to use? Keeping goal number one in mind simplicity is key. Not having to replace parts that are in good working order is key (mostly considering the rear axle here but I'm not even sure it's good yet). Point is as of yet I haven't settled on a plan. Miata 1.6l and gsxr1000 motors are both contenders currently since they are both sitting in the garage. But those don't have to be the only options. 

Maybe I go stock motor and do a 60s club racer vintage build? 

Maybe I go Miata power and shoot to drive it to the challenge from Chicago?

Maybe I go gsxr power and strap a turbo to it for extra breakage?

For now, my task is to clean up the frame, make any necessary fixes, and get the brakes and suspension in good working order.

Finally, I'd like to also try in this thread to tally the hours I spend on this project. Mostly for my own curiosity. Yesterday I spent about 4 hours and today about 2.

6 hours in.

It all looks doable.

You never really bite off more than you can chew, you just have to chew a little longer.

If this is the rusty one, the not rusty one should be pretty nice.

Any idea what kind of shape the old engine is in?

These are SO COOL.

Really looking forward to what you come up with for it.

In reply to Robbie :

Given the rust I’d say drop in a Wankle & call it the Rotsun. You could pronounce it either way & it would still fit. 

You could keep it all Datsun and put this in it.

https://grassrootsmotorsports.com/forum/parts-sale/datsun-drivetrain/161185/page1/

I still want to see the X1-9 at the challenge... But this should be fun too! Carry on!

2020 - year of the tiny vintage roadsters. This Datsun, the X1/9's, the two TR4's, this is gonna be good!

I like this already! And its probably already better than the amc we sold you.

If this gets finished and you want to sell it after the challenge let me know 

Definitely interested to see how this plays out.  Have always liked these little roadsters.

Cool cars. I'm looking forward to the build. I've seen two of those at a local junkyard. I can go back and check if there's anything you need, but they looked pretty far gone.

Here's a clean one for reference.

Old engine is there (and I got a second set of carbs in the trunk), but other than that I haven't touched it yet.

It is technically the 1500 engine, which I think might be a bit more rare than the 1600 engine, but hard to say if it's worth much yet. One of my upcoming tasks it's to see if I can get the motor to spin. I do know I'm missing the starter so compression tests will be hard, but maybe I can leakdown.

Honestly I will probably snag the oil pan and vavle cover off for visual inspection, and if things spin and look ok at that point, then I'll have a good idea. But since I think my odds of using this engine are low, I'll probably be looking for the useable parts to sell off.

So in for this. 

akylekoz said:

You could keep it all Datsun and put this in it.

https://grassrootsmotorsports.com/forum/parts-sale/datsun-drivetrain/161185/page1/

Yeah, trust me I'm considering. I'm a bit worried the 1200 would be pretty short on power, but maybe not?

It properly is very close to a drop in solution, and it terms of goal number 1...

Rotory would be cool too, but since I've never hung out with one in person im afraid the learning curve would be too steep (not only how it works but how to get good cheap parts, what mod works and what doesn't, etc)

You're crazy.

also put an rb25 in it

AWSX1686 said:

I still want to see the X1-9 at the challenge... But this should be fun too! Carry on!

The x1/9 will make it eventually. But we are currently a bit lost considering powertrain. While the bike motor sounds like a great idea, my true dream for that car is something super reliable. And I'm worried about my chain drive being the right solution for that.

maschinenbau said:

2020 - year of the tiny vintage roadsters. This Datsun, the X1/9's, the two TR4's, this is gonna be good!

It can sort of be radwood, because these cars are what would have been at the challenge in the 80s and 90s...

But regardless, it would be awesome to see all the vintage roadsters. Andy has(had?) That $40 spitfire that should join the party.

Dusterbd13-michael said:

I like this already! And its probably already better than the amc we sold you.

If all wheel drums are better than all wheel disks, you might be right.

In reply to AAZCD :

Wow! Two!

I actually may be looking for the bigger diff that came in the later roadsters like those, but I need to do a bit of detective work first.

Patrick said:

You're crazy.

I'm starting to believe you 

IMHO, so that the car has something to do after the challenge, thinking about vintage racing it is a great idea.

And for the car you have, all that really means is that whatever you do for the challenge, make it reasonably easy to undo it.

It seems to me the easiest install would be a 4 cyl engine of some type, and adding a turbo would be the power solution.  On that, I'd look for the most common one you can- Miata, 240SX, etc powertrain (engine + trans) you can find.  No idea how much power you can put through that axle, so perhaps even look into an entire first gen RX7 powertrain with a stick axle and turbo.  At least, the axle will be strong.

I could be wrong, but re-engineering a leaf spring set up to a 3 trailing + panhard set up would be pretty straight forward.  Look into what vintage race series allow for that- it's possible that they allow that kind of re-engineering, too.

Then use the roll bar rule to stiffen up the chassis.

Great car, have a blast.

(the X1/9 should probably get the Honda 2.0 monster swap- or perhaps look at the turbo 1.6 Civic that won the challenge many years ago, and copy it's powertrain- common, simple, turbo friendly)

Elliott and Bill Harvey have been running this same one since I started autocrossing in 1983: