Hello everyone.. first and foremost., my Name is Shamus... While researching the Datsun Roadster many of the questions I googled about this subject would link me up to this forum. Many of the questions and answers were very informative. You all have a great group of knowledgeable car enthusiasts not to mention some great looking and performing cars. So imagine how ecstatic I was when I happened to stumble upon this 1969 SLR311-12xxx with a U20 OHC ... (wait for it)... twin Mikuni setup... Now, I’m not an avid Datsun Roadsterholic, yet, but if anyone is reading this post, can you tell me if I have a special engine here? One worth keeping pure? She runs good.. lots of power, but she runs rough meaning a little TLC should do the trick. I look forward to your guidance and am such a proud owner of her.. I finally got my classic and she was born in the same year. going forward., any assistance in pointing me toward that right direction is deeply appreciated. Mike Young set me up with Sports Imports for the floorpans which my wrench then concluded wasn’t so bad. Now., I’m looking for the weatherstripping and rubber. Some of these sites are ridiculously priced. And I’m not sure if aftermarket are worth it but maybe All there is and better grade?? Can someone answer that?? She has been in my life now for less than a week and I have to start digging for parts. Thank you All again in advance and hopefully we will see you soon.
Last edited by Shamus980 on Mon Apr 23, 2018 9:48 pm, edited 1 time in total.
Welcome! You have a preferred set-up but not a “special†engine. All U20’s could be configured this way at the dealer, and this can be done “readily†with the right parts. That said, you have the (very) expensive parts and that is special. As you will find with a classic car, especially one in limited production, restoration and parts are expensive! Our vendors do a pretty good job moderating that cost while still offering top quality parts.
"When all else fails, force prevails!" Ummm, we're gonna need a bigger hammer here.
Thank you. As many of you have experienced upon the drive back home with your roadster on the trailer behind. Many thoughts on the restoration and modification of your new found toy began swirling around in your thoughts. Body., chassis., engine., paint., interior. Do you keep her pure or do you modify her to keep up with the times? WHAT TO DO?? I’m more of a purist., but my busy schedule leans for a reliable., ergonomic., let’s jump in and take a long drive. I can’t risk being stranded waiting for a tow. There lies the dilemma. Not to worry people., I’m going to drive this puppy this summer and see. The restoration begins in October. Alvin on this site., is making the choice that much harder. After reading his posts it seems that was the right choice. He has had a full lifetime of memories with his roadster. Either way., thanks for your hospitality in welcoming me to this new band of fellow roadsters.
Tom (notoptoy) pretty well covered the parts pricing issue. Dean (datsunparts.com) one of our vendors has mentioned before that manufacturers often require that 500 pieces be purchased before they will tool up to reproduce a part. He then has to decide how many pieces of the part he will be able to sell and how many will just sit on a shelf. Now he has to determine a price that customers will pay and still show him a profit, keeping in mind the initial cash outlay on which he is paying interest. There are still some NOS parts out there, but the more commonly needed ones are not always available. Our aftermarket parts are nowhere as inexpensive as those for Ford, GM, or Mopar. If your looking for a inexpensive sports car to restore with excellent parts support than you might want to consider an MGB or a Triumph, but then you wouldn't have something as unique as a Datsun Roadster. While the parts for the Datsun are not as cheap as the aforementioned brands, they are not near as expensive as parts for some of the more expensive European cars. The silver lining is that the Datsun's are starting to rise in value and if you have a decent starting point and are willing and capable of doing the work yourself you might just break even! It's often said that when restoring a car that it will take twice as much money and time than you originally thought. HEED THESE WORDS! Now's the time to make your decision, and we all here hope you decide to proceeded on!
Mike M
Old enough to know better, too old to remember why!
1969 2000 solex mine since 1972, under resurrection. (Finally resurrected as of spring 2019!)
1969 Porsche 911s -worth more, but not as valuable! Gone!
2017 Lotus Evora 400 - Oh my!!
I have recently acquired a huge lot of rubber for the Datsun roadster and my prices are very competitive as the bulk purchase I made was far below cost and I am passing the savings on. make a list and email and I will respond asap.
Ross M
sports imports
rubber for 510-521-620-240-patrol-311
Welcome Shamus! A Datsun Roadster is generally a very reliable car, but every one has had previous owners and are an unknown at this point. You do have some great hipo parts, and it sounds as though they were set up pretty well to begin with. But, there are some things for you to learn and to address or check immediately. First remove the valve cover and check the condition of the "evil L"... it is the L shaped part of the upper chain guide that sits in front of the cam gear. Over time, the chain can strike the underside of it, leading to being cut off and then flying through your engine with a high degree of velocity. Check it and report back. Also, check the upper tensioner to see if it has been shimmed, as this is the technique that keeps this from happening. Look over the valve train and check the rocker arms for deterioration. You can check your valve adjustment or lash at that time too if you want, suggested is 6-8 intake, 8-10 exhaust cold. Let us know if you're not familiar with this process. Next, check your front (and rear?) brake lines to see if they are covered by the black plastic coating that was supposed to protect the line but can cause them to corrode once compromised. This covering can be removed. Look for leaking wheel cylinders, and flush the brake lines unless they were done recently, as the cylinders can corrode. While under the car, check for debris building up in the wheel wells behind the front tires and forward the rear tires... stuff builds up here that leads to rust. Next, check the floor of the trunk for cracks caused by the gas tank being bolted to it. Look inside the tank for floating crap or rust, and strongly consider swapping out the fuel filter or checking them for stuff, especially if the car has been sitting.
When swapping in the hipo parts (carbs and cam) the ignition timing is changed. Before that however, when switching a previously "pollution controlled engine" to pre-68 specs the timing curve should have been replaced with the early curve, and the ignition timing set to 17-20 at idle vs 0 in the later cars. If the slogged curve distributor is set to non smog initial settings (17-20 degrees advance) you will put way too much total advance into the system. My guess is that all of this was changed long ago, but again, who knows? Check your timing with a timing light and report back.
Regarding the carbs, post some pics so we can see what version they are and can make suggestions on tuning and cleaning. It will be important for you to understand how these carbs work and to learn how to adjust them. However, once set they should work great and not require much fiddling in the future.
What is known about the trans? It's a great box but had a problem where things would loosen up and allow the 5th gear to walk off, leaving you with a box of neutrals. No way to know by looking on the Outside to tell if it has been fixed yet.
Last thing I thought of was to make sure the oil filter tube is still present when you remove the spin on filter. There is a metal tube that fits inside the filter that can come off and stay in the filter, being thrown away. Don't use the mobile one filter that is available as it won't accept the tube and still drains back. This leaves your engine starving for oil up top until the pump fills the filter, causing the chain to slap against the guide as the tensioner is activated by oil pressure and a weak spring (thus the need for shims).
This may sound like a lot of stuff, but it's really not. I've had my car over 32 years, and like many have driven across multiple states at high rates of speed for 10-12 hours without problems. Certainly not a luxury car drive, nor completely dry in the rain, but an absolute blast. NOTHING beats a convertable in the mountains, and the sound of the solex/mikuni set up will keep a smile on your face!
Welcome to the family, enjoy the ride!
Beautiful car! I think the best way to figure out the plan for your restoration is to DO NOTHING and drive the car for the summer. Then you'll get an idea of what you really want to do. I would go in this order personally:
Brakes inspect and replace anything leaking or worn out
Engine - tune and jet the mikunis for your driving style/altitude/temperatures. You can do this with a $60 Colortune Spark Plug and a $25 airflow "snail"
Hoses - check that the lower radiator hose hasn't rubbed on anything. Check that heater hose isn't leaking into the cockpit
Gauges: make sure they are all working especially the Temp gauge
Rust: start by just finding it all, then coat with POR-15 paint ($60) so that you can keep driving the car and not worry about it.
Hello everyone.. first and foremost., my Name is Shamus... While researching the Datsun Roadster many of the questions I googled about this subject would link me up to this forum. Many of the questions and answers were very informative. You all have a great group of knowledgeable car enthusiasts not to mention some great looking and performing cars. So imagine how ecstatic I was when I happened to stumble upon this 1969 SLR311-12xxx with a U20 OHC ... (wait for it)... twin Mikuni setup... 
Now, I’m not an avid Datsun Roadsterholic, yet, but if anyone is reading this post, can you tell me if I have a special engine here? One worth keeping pure? She runs good.. lots of power, but she runs rough meaning a little TLC should do the trick. I look forward to your guidance and am such a proud owner of her.. I finally got my classic and she was born in the same year. 
going forward., any assistance in pointing me toward that right direction is deeply appreciated. Mike Young set me up with Sports Imports for the floorpans which my wrench then concluded wasn’t so bad. Now., I’m looking for the weatherstripping and rubber. Some of these sites are ridiculously priced. And I’m not sure if aftermarket are worth it but maybe All there is and better grade?? Can someone answer that?? She has been in my life now for less than a week and I have to start digging for parts. Thank you All again in advance and hopefully we will see you soon.
