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1970 Datsun 2000 Roadster SR20det


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Hello Everybody,


I rebuilt a Sora blue 1970 roadster 2000 in high school, which I regrettably sold for a sport bike. I have missed that car ever since, and have longed to build another one. Since selling the roadster, I have a couple of SR powered s13 coupes. I knew that I HAD to put one of these in the next roadster! I know it is not a Z car, but in the Fairlady lineage, it is technically the predecessor to the 240Z.


At the beginning of my last semester of college up in Kansas, I purchased another Sora blue 1970 2000 Roadster for $900 and a stick welder to sweeten the deal. This roadster was very rough, but rough in all of the right places. The original U-20 had been replaced with a feeble R-16 (that was totally seized), The interior was shot, there was a horrendous attempt at flares done in the rear, and all the tires were dry rotted. Perfect, I wont feel guilty about gutting this one! After purchasing, it was dragged back to the side of my parents house in the Dallas area.


In my mind, I would graduate college and have plenty of disposable income, and a nice garage to store the car. Not so. She sat for over 2 years under a cover until I moved from Kansas to Austin, TX. Being much closer, and having a better paying job has finally allowed me to start making progress. The progress is slow however, as my apartment has no garages, and I am limited to occasional weekends, and my PTO to visit my family in Dallas, and work on the car. I have purchased a membership at this place called Tech Shop in Austin. It's a community based workshop that has all sorts of welders, metalworking tools, sandblast cabinets, powdercoating booths; all sorts of stuff! So the plan is to rebuild the small stuff at the Tech Shop, and spend the occasional weekend working on the body, chassis, and bigger stuff.


The overall plan for this car is basically a stripped down, ridiculous street toy. I will post photos of the progress thus far in the next posts, and look forward to documenting the entire build on HybridZ.


Thanks for reading and have a good day,






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For those interested, here are some pics and vids of the first roadster i built.







Some revs: 


While im at it, here's an XR500r I built in college: 






Okay, here is the new car's first day at her new home:









Time to start stripping  :P

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A weekend was spent removing the R16, and while I did not get any pictures of the process, it was a pretty funny story, I had a good friend of mine over, taking everything apart, and when it came time to pull the long block out, we set an extension ladder across the front fenders and strapped the motor to it. We each lifted one side of the ladder and walked the motor forward out of the car. Ha! anyways... Pics!




My dad painted a motorcycle tank on his hood. <_<



After this, the car sat for a while until i took a week of from work. Spent it all continuing to strip the car.



Ewww Yuck!



Typical "old Datsun rat shit"



Scraped up all of that tar based insulation. (PITA)



Oh Noooo! found some cancer eating through the driver's side floor beneath the pedals



I don't know what I'm going to do to the suspension/brakes


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Another weekend was spent on removing the front end. I was able to remove the suspension and brakes, but the ball joints on the steering components gave me trouble and was left on the car.




The ball joints are shot. 2 uppers and 2 lowers will run me $490...OOOF! thats a kick in the nuts. I might try and retrofit some other ones. That sucks!



Suspension components disassembled and ready for some sandblast and powdercoat.



After reseaching bearing and hub dimensions, the plan of attach is to try and find some 87-89 z31 turbo front hubs. If I have the inner bearing diameter bored to 62mm, I can press in the original roadster front inner wheel bearing, and the outer wheel bearing inner diameters match up. However, I believe the hub length of the z31 is shorter than the taper of the Roadster spindle, so some machining may be required.If i can get these to fit, I could run Z32 4 pistons and 11" rotors. and a 5 lug on a Roadster would be pretty slick. I found a junk yard an hour away that had a fresh 88 turbo, 90 and 96 NA 300zx. I went there with high hopes, but the ONLY things that were removed were the hubs, brakes, and MAF's on all three. Day wasted. ;)

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Thanks Josh,


The plans for the car, are just to build it up overkill. I'd like to just have a toy that I enjoy driving, turns heads, and will give some of the rich people around here and their fancy cars a run for their money. I would also like to get into some sort of motorsport, most likely starting with autocross. Maybe a couple track days.



So after this post, this build thread will be up to date, and any future updates will have to wait until the work gets done :P


I found a kid in Tyler, TX who was selling off an abandoned S13 SR20det black top build. He had completely disassembled the engine. He did it properly too! everything was bagged and tagged, and organized in tubs. The block had been hot tanked, and the crank had been machined .50mm over as it had a spun bearing.

He had also purchased:

86mm 9:1 CP pistons

Manley forged rods

ACL Race bearings

OEM Timing set

Oem timing cover

ISIS water pump

New freeze plugs


I got all of this for $1800. came with an engine stand too :rolleyes:


I also met up with a guy in Arlington and bought a set of circuit sports rocker arm stoppers, OEM valve seals, and ARP head studs all for $200.


After selling the wheels to a friend for $150, that puts me at a total of $2750. I want to keep a running total of this build just for shits.








So the SR20 is now mine! I have found an exceptional machine shop here in Austin, but they strictly do heads. The head is in pretty decent shape, and can probably be reused as is. But, why would I since its already off. February is bonus month, and I will be taking the head for a valve job, and new guides pressed in. I want to assemble the head myself, and plan on doing BC springs and retainers with 256 poncams.


As for the block, I am open to recommendations for a reputable machine shop that will touch an SR. I need the deck resurfaced, the cylinders honed, the crank balanced for the new reciprocating assembly, and all of the clearances checked. (bearing, cylinder to wall, etc) Please give your input on this. Anything around Austin/Dallas/Houston/ or anywhere in between is a-okay with me.

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I made a little progress today. I went and sand blasted the front suspension sans the ball joints and powder coated them. The Lowes that is connected to the tech shop carries some specialty items, and they sold powder. I thought I had bought black, but turns out it was called "black chrome" jeez i need to stop drinking while i work on this thing. Oh well, maybe it will add a little bling to the chassis. They turned out okay, a little splotchy in some areas, but overall a deep shiney dark grey.


















Time for a beer, Cheers!

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  • 4 months later...

Been a while since I've given an update. The progress on this car has been pretty much limited to just buying parts. I recently picked up a 1972 240z driver to fart around town in, so the Z takes up all my time, and the Roadster takes up all my money :-)


Here's the new stuff:

I had to bite the bullet and order the ball joints. there was no way around it...$500 for 2 uppers and 2 lowers.



$200 bucks for 1989 z31 turbo front hubs. I will be taking these to have the bearing diameters bored to match the roadster wheel bearings. should be a straight forward bolt on after that.



NIS DIV2 16x9.5+0 5x114.3 - $700




Top mount T25/8 manifold, down pipe, and lines off of ebay. I'm impressed with the quality for the price tag. $400 for all



Since I had some good luck with the quality of the ebay exhaust parts, I tried my luck on a $100 intake manifold. big mistake. 

this thing is total crap. lesson learned.





I'm still waiting on a few more parts to arrive for the front suspension. I ordered all 18-8 stainless hardware from McMaster-Carr for $80, Bumpstops for $15, Dust seals for $30, and scored a very nice pair of Z32 aluminum 30mm calipers for $190. The plan of attack right now is to finish the front suspension, get the Z31 hubs and Z32 brakes to fit while I continue to prep and paint the frame. Before I install the front end, I plan on ordering the nissan comp lowering springs with a 23mm swaybar. I have also been pursuing (with little succes) a ford 8.8 posi/disc brake rear end. I've found a couple with 4.10's already, but craigslisters never seem to respond to me. Anyways, I'll also soon be ordering some RE-11's in 245/45r16 as well for rear end/fender flare mockup.


$4965 total. oof, My goal is <$12000 I'm getting there in a hurry

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  • 4 months later...
Wow it's been a while since progress worthy of an update. I've been traveling for work a bunch recently. I did make quite a bit of progress, I feel. So to start off, I picked up a ford 8.8" rear end, It was from an explorer, disk brakes, limited slip, and 3.73 gears. This thing sat in the back of my truck for a very long time while I researched how to narrow a rear end.
After feeling confident I could narrow it myself, I had to know how much. This required me to wrap the rims with some rubber, so I could mock it up underneath the body. I ordered up some Bridgestone Potenza Re-11 in 245/45r16 through tire rack. Definitely some fatties. Rims again are NS Wheels Div2 16x9.5.
Putting them underneath the car, I measured out that I would feel okay with narrowing the rear end down to 50" from like 59" and some change. So to narrow this thing down I ordered some bushings that fit where all the bearings go, and a 55" 1-1/4"dia tgp steel bar. This is required for keeping everything in line while it is being welded back up. I spent a night disassembling the rear end and grinding off all of the old brackets.
Measure 20 times, cut once. I hope I don't eff this up.
All lined up with the jig
To keep the axle warping after welding, I would stitch weld 1" let it cool, stitch another 1" on the opposite side, and repeat until it was all welded up. Then I ground down the weld flush. Rear end narrowed! I still need to cut the axles an dI'm going send them off to Moser Eng. to get resplined.
I was recommended a good machinist to bore my Z31T front wheel hubs. He did great work opening them up to fit the roadster wheel bearings. 
I pressed in the races tonight and did a test fit on the spindle. It fits better than expected honestly. I have about 3mm of slop, and am going to have to fab a steel spacer to push the outer wheel bearing outwards a little above 3mm.

Well that's all for the car, but I just got an apartment with a garage lined up in Jan, so I'll be able to bring the car down to Austin. Progress should start to pick up rather quickly :)
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  • 2 months later...

Interesting project, keep us posted! And don't be shocked if the $12k goal gets hit early :)

Ha! yup.... Im 400 buck shy of 10 grand. new goal. 20k  :2thumbs:


I'm in Topeka, I'd love to come check this thing out. Where abouts are you?

I used to live in Lawrence, then Overland Park, but now I'm down in Austin TX and the car is In the Dallas area at my parents house. I'll finally be moving into a place with a garage, so when i can get this thing into a rollable state, it's coming down to Austin to live with me  :mrgreen:.


Been a while since i've updated! i took a couple weeks off from work, and was able to make some progress on the car. I picked up another abandoned sr20det built. same deal as the first one. this one however, instead of having all of the aftermarket bottom end parts, had all of the parts i was still needing to buy.


Tomei Poncams

Tomei valve springs

head was resurfaced and had a valve job done.

Tomei 1.2mm MLS headgasket.



The block was trashed via spun main bearing, and I will be using it as a mockup block while the good SR is being built. Also it came with a plethora of new parts that I won't be using, and can sell to get some money back.


I spent the last week cutting, grinding, and welding on the frame. the cross member and x member were notched to clear the SR oil pan and transmission mount. all of the leaf spring brackets were cut off to make room for the 4-link brackets. I've decided to attempt a triangulated 4-link setup in the rear with 3/4" heim joints and 1.25"od .120 wall DOM tubing. We'll see how that turns out once the rain stops, and I can get back to weldin'.


I mocked up the front suspension on the car so I could see where the hub swap places the wheels, and it's not as bad as I had thought it would be. Fender flares were part of the plan all along. I'l have a better update next weekend for sure, but here are a couple pics.










Hope everyone had a merry Christmas!


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