Datsun Roadster Forum-311s.org

I like the red interiors if the exterior color is complementary. It's just one person's opinion, but this car would look odd to me with a red interior. Someone step up and pre-purchase this beauty and help Michael out with these details to your preference. I'd love to own one of his wonderful creations, but they are a bit beyond my means I'm afraid. Looking forward to following the build.

On project Sting-Grey the choice of interior color was easy-- the grey and red were very complimentary.



Black and White exterior colors also looks great with a red interior too-- but with this exterior color, it could be polarizing. The line between cutting edge and striking, or garish is pretty close-- thankfully I do not need to make a decision about interior for awhile, so we will see what happens-- and as Bajaroadster says-- maybe someone will buy this and make that decision for me!

The Frame Returns

The frame was finished at the blasters yesterday, so I did a quick trip out to pick it up-- there is something fantastic about getting a clean frame back (not quite as good as a freshly powder coated frame, but this will be really nice to work with now!)

My old Nissan Hardbody did the hauling duties:



I spent about 20-minutes blowing the remaining sand out of the drain holes until no more was coming out-- trying to keep this as clean as possible.

Then the frame was setup in the shop, ready for this weekend's fabrication work:



Everything is nice and clean now, and no holes where the frame pads were-- so that's a win!



I had the blasters mask the VIN area off as to not erode the numbers-- and that worked well:



More updates this weekend!

-m

Fabrication Begins!

With the clean frame setup in the shop, it was time to get cutting to do the mods for the SR20DE swap. This has been well documented in the Hybrid How To-- S13 SR20DE swap into a 1969 Roadster build thread in the Engine Swap section: viewtopic.php?t=5128
That build thread was started 18-years ago(!), but not a lot has changed in our process.

First to go is the original motor mounts:



The original mount locations do not work with my SR20 motor mount kits, so we cut these off and build new ones. A nice cut off wheel makes quick work of the removal of these:



With the motor mounts out of the way, it is time to do the front crossmember modifications. For those who are not aware, the front crossmember is a multi-layered design with an internal crossmember that is welded to the outside skin. For oil pan and front pulley clearance (and to make installation of the engine much easier, we remove the outside skin up to the internal crossmember as illustrated below:

Looking at the outside skin of the crossmember, you can see the welds where the internal crossmember is welded to the outside skin:



We cut off the cap that goes from the edge of the crossmember to the internal braces-- using a plasma cutter, it makes quick access to this portion:







With this out of the way-- a new cap is built out of 16 gauge and welded in position.

(Apparently did not take that photo-- will come back and add one when I take the engine back out)

With the front crossmember mods done, I could now install the new motor mounts. We have been selling SR20DE(T) motor mount sets for 25-years, and have an engine mount rental JIG that places the motor mount base plates in exactly the correct position on the frame getting the ~5 degree mount that the engine sits at correct, as well as placing the transmission shift thru the center of the 1600 shift hole-- it all lines up perfectly.

The JIG was installed on the frame, clamped down, and now it was time to weld the motor mount base plates to the frame. First, we start with a cardboard pattern of the base plates to determine how much will need to be trimmed from the base plates provided with my kit:





Please forgive the appearance of the JIG-- it is just made from scrap metal, and this one has been in my rental fleet for years....



Base plate trimmed up, bolted on, and ready for welding:



Passenger side gets the same treatment:



With the base plates welded on, I could then build side gussets to support the base plates-- and then it was time for a first test fit of my mockup engine and trans:





Driver's side motor mount:



Passenger side mount:



And finally, an overall shot-- engine sitting in position, with the correct tilt and rake-- transmission mount next!



There is still a TON of work to do on this frame, but it was a solid weekend of progress for Project Mako!

Michael

Great start!

Alternator Notch

Small progress this week-- got the alternator notch finished on the passenger side of the frame



This allows us to use the smaller Subaru Justy alternator in the stock SR alternator position (with our conversion bracket)...

A small, but important modification. Transmission mount next!

Michael

Transmission Mount

The SR20DE(T) 5-speed transmission is long and requires a notch in the X-frame to allow for mounting-- this post will outline how we modify the X-frame to allow for a clean solution.

With the engine and transmission sitting on the motor mounts-- we can now see the interference with the transmission mount to the X-frame:



By a happy coincidence, the pinion angle for the rear of the transmission is the same height as a 2x4 mounted on its side-- now that we know how deep the transmission needs to sit, we can get cutting. The X-frame will need a notch to allow the isolator to have a place to sit, and to make it easy to bolt into the car-- so out with the plasma cutter:



Now that that is out of the way-- we can box this all back in again:



A pattern is made as the base plate for the transmission mount:



Now we can put the mock-up engine and transmission back into the frame to determine the transmission mount height. First the isolator needs to be installed onto the transmission-- we use the Energy Suspension GM Transmission Mount-- part number 3.1158G:



This bolts up perfectly to the base of the 5-speed:



With that done, we put the mockup engine and transmission back in the frame to determine how much will need to be removed to allow for mounting of the transmission:





One last check to make sure that the engine/trans are still level side-to-side:



Then it was a matter of crawling under the frame, putting in a few tack welds from the underside, and then removing the engine and transmission so it could be fully welded in:



And now without the trusty 2x4, the engine and transmission are finally sitting on their mounts:



Success! I still need to add a new top reinforcement plate, as well as a new bracket to tie the front legs of the x-member together using the transmission mount holes, but those will be built in a couple weekends from now as the air compressor died. No more cutting with the plasma cutter until I get that sorted...

I still wanted to make more progress on Project Mako, so I worked on a few other things-- first was the brake bias valve. With the upcoming rear disc brakes, we like to use a Wilwood brake bias valve to have the ability to adjust the bias if necessary. I like to mount these on the frame--- but first we needed a simple bracket:



And this was welded to the frame behind the body mount (where it would be protected):



Now the brake bias valve can be mounted (which will be done after the frame is back from powder coating):





I also started working on a rotisserie that will be used to rotate the frame for the underside work and so I can weld in the proper position-- I'lll have details on that when that is complete.



Good progress-- one small bit at a time...

Michael

Looking great! Thank you for meticulously documenting the process as well.

Man, I'd love to be able to drop my car off with a blank check... such outstanding work.

Spin to Win

Last weekend I mentioned that I would be building a small rotisserie to allow me to easily rotate the frame so it would be easier to weld in position-- here is how that was built...

I often will pick up cheap engine stands at garage sales, and I had a pair of them in my container that were perfect for the task. The uprights were cut off to make them vertical so the rotating heads would be parallel. Cut, measure, and weld. When I had both of them vertical and the same height, I built the brackets to mount the frame to the rotating head.

The rear was easy-- just two brackets that connect to the bumper mounts welded to some 2" angle iron:



Since the rear of the frame is higher than the front bumper mounts, I used the horizontal slots on the engine stand to set the frame height:



In the front, I did the same thing-- two simple mounts to the bumper mounts to the same 2" angle iron:



Since the height is different, I used the angled slots to set the frame height parallel:



The nice thing about using the engine mount heads is that they are easy to adjust to make things parallel and balanced-- with a few quick adjustments, the frame easily rotates position:



With the frame upside down, I could now weld the underside of the motor mount gussets:





And finish the welding of the front crossmember notch (and do the finish grind):



Observant readers might notice that the base of that crossemember had seen better days with some rough and ready jacking at some point in its life-- I kept staring at that, and could not leave it, so out with the cutting disc-- a few cuts and out with the spot weld drill and the battered skin was removed:



Unfortunately, I did not have any 14-gauge steel today, so I'll get that rounded up this week and I'll get the base of the crossmember re-skinned. I'll then add a jacking point/oil pan protector that we do on all our swaps-- but you will see that in the next update...

Michael

Nice rotor!
Do you have one suitable for the body?
I have some plans if you are interested

Yes, we have a body rotisserie and have had quite a few roadsters and 510s on it over the years...







A rotisserie really makes things easier for sheet metal repairs...



Michael

There's something about reading through this "real time" and anticipating the updated progress that adds to the excitement - you can sense the level of planning and experience that it takes to do this in an efficient manner as well as the necessary shop space and tools. Thank you for taking the time to share the build process at this level of detail!

Fantastic work!

Phenomenal work and beautiful welds! After doing this many cars, something that seems like rocket science to the rest of us is probably close to routine for you now. It must be a rewarding feeling to take forgotten shells and give them new, modern-powered life.

Thank you Greg and Erik-- and others who have chimed in regarding this project-- I really appreciate the support.

These projects take lots of time, money, tools, and space, but they are well worth the effort when complete. There is something very rewarding about taking some of these forgotten dreams, and bringing them back to life with a reliable, "modern" drive-train-- all of our conversion cars have been derelicts that had been sitting for years (or even decades), and are now being enjoyed with a new heart.

I just need to remember to slow down and document even more for the new future owner, or to inspire others to try their own swap. Facebook ruined build threads like this on so many forums, so I am committed to documenting as much as possible, and having a format that others can refer to on how we solved some of the conversion hurdles.

Someone is going to get a really nice car with Project Mako, and this documentation process with help a potential buyer see the value of what they are getting with a real record of why they are investing in such a project-- and for those who are not buyers, a tool to help them along with their own project--- sounds to me like a win-win!

Michael