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damarble
damarble New Reader
12/28/20 12:21 a.m.

It was suggested I make a dedicated thread for this build so here it is.

The patient is a 68 Datsun Roadster, 49k original miles, one owner "barn find", except that barn was a carport where she languished for the past 44 years.

While everyone, including me, likes original survivors, I like restomods even more. The 96hp 1600cc engine was never going to cut it, even though I was assured it turns over and will run with some work. The go-to big power engine for these is the SR20DET from JDM Silvias, but those have dried up and for the current prices I knew I could do better. Enter the 2015-17 Mustang 2.3L Ecoboost. It's fairly big and will take a little more work to make fit, but 310hp/320tq on the stock tune will make this 2000lb car a rocket.

I've placed my order with Mars and now have a 10-12 week wait for delivery. They are the only outfit offering a turnkey 2.3EB. The initial price of $5k was a hard pill to swallow, but I'm also paying for lack of frustration and wasted time trying to put it all together myself. Best case scenario I could have maybe found an engine for $1500-2000 and the control pack is $1600, but how much little stuff would I have to track down?

I'm currently debating if I want to use a NC Miata 5 speed, which should fit in the trans tunnel, or the 6 speed, which will require cutting.

While I wait 3 months for my engine there are many other things that need to be done to make the car road worthy, starting with all new and upgraded brakes. I don't intend on doing any cosmetic work until it's a running car.

 

 

Mr_Asa
Mr_Asa SuperDork
12/28/20 12:50 a.m.

Other than the price, sounds like a challenge contender.  Interested in seeing it develop.

noddaz
noddaz UltraDork
12/28/20 7:28 a.m.

Whoa.

Where is the button to save this build?  

TVR Scott (Forum Supporter)
TVR Scott (Forum Supporter) Dork
12/28/20 7:29 a.m.

Looks great!

jharry3
jharry3 HalfDork
12/28/20 7:30 a.m.

With all that power what are you going to do to beef up the brakes, wheels, tires?   

jr02518
jr02518 HalfDork
12/28/20 7:35 a.m.

I will also be watching and look forward to the development of your project.  First question, will you be separating the body and frame for your build?

David 

Yes!

damarble
damarble New Reader
12/28/20 8:16 a.m.
Mr_Asa said:

Other than the price, sounds like a challenge contender.  Interested in seeing it develop.

I'm guessing in about 5 years the prices will be a lot better and people will be flocking to the early adopters' threads.

 

Dropped the tank. Need to clean it and modify for efi. 

 

dherr (Forum Supporter)
dherr (Forum Supporter) Dork
12/28/20 9:21 a.m.

Watching this one, as I do like resto rods much more than just a stock rebuild. Nice engine choice, but you will definitely want to upgrade the suspension, brakes and rear to accommodate that much of an increase in the power. My MSM has that much power and no electronic "nannies" to keep it pointed straight, so I can only imagine 300+ HP in that chassis. Looks like there are lots of options for upgrading the rear.

AngryCorvair (Forum Supporter)
AngryCorvair (Forum Supporter) MegaDork
12/28/20 9:25 a.m.

In reply to noddaz :


 

Click on the eyeball and the thread is added to your watch list

damarble
damarble New Reader
12/28/20 10:07 a.m.
jr02518 said:

I will also be watching and look forward to the development of your project.  First question, will you be separating the body and frame for your build?

David 

It will probably have to happen at some point. Frame mods will be required, at minimum to run the exhaust down the passenger side, possibly for transmission fitment as well. 

damarble
damarble New Reader
12/28/20 10:10 a.m.
jharry3 said:

With all that power what are you going to do to beef up the brakes, wheels, tires?   

Initially I'm leaving the rear alone, just new drums, shoes, cylinders, lines, since it's all frozen and trashed. After it's running I will likely build a limited slip disc brake 9".

For the front I'm running 300ZX hardware from spriso.com

 

damarble
damarble New Reader
12/28/20 10:14 a.m.
dherr (Forum Supporter) said:

Watching this one, as I do like resto rods much more than just a stock rebuild. Nice engine choice, but you will definitely want to upgrade the suspension, brakes and rear to accommodate that much of an increase in the power. My MSM has that much power and no electronic "nannies" to keep it pointed straight, so I can only imagine 300+ HP in that chassis. Looks like there are lots of options for upgrading the rear.

I think this build will be terrifying to drive if those upgrades aren't done. Baby steps, I'm gotten bogged down trying to do too much at once on past builds. 

damarble
damarble New Reader
12/28/20 10:21 a.m.

So the biggest obstacle I face is the high pressure fuel pump. It's in a very inconvenient spot, on the back of the head mounted high. I have to cut into the body here, no way around it. Also you see I have about 31" to the ground there. In stock form the Mustang 2.3 is 29.5", giving me no ground clearance. By switching to a NC Miata oil pan I can cut that down about 2" off the bat. The HPFP is also the highest point, and may require a slight bump in the hood to cover. 

 

damarble
damarble New Reader
12/28/20 10:29 a.m.

A non turbo duratec actually fits really nice. 

 

This drawing gives a good idea of where fat needs to be trimmed.

Robbie (Forum Supporter)
Robbie (Forum Supporter) MegaDork
12/28/20 10:44 a.m.

AWESOME! I've got a roadster that is 'slightly modified'. Looking forward to watching this build. Where are you located? I have a stock tank and though I haven't looked inside it might be better than that one... (I'm in chicago suburbs)

The one on the right is mine, now sporting a 600cc honda CBR engine behind the driver and a tube frame from a derelict formula car. The one on the left is powered by a turbo ka24 and the owner's/builders are also around on this forum. You're in good company!

Snowdoggie (Forum Supporter)
Snowdoggie (Forum Supporter) Dork
12/28/20 10:53 a.m.

Wow. Waiting to see how big a shoehorn you need for this one. 

 

On the other hand, it is nice to know that if my Mustang throws a rod that it will cost me half the price of a Coyote engine to replace it. 

 

damarble
damarble New Reader
12/28/20 11:19 a.m.

In reply to Robbie (Forum Supporter) :

Very cool. 

I'm in eastern Washington. The tank metal looks pretty solid actually, I think it's just the 44 year old fuel looking bad. This used to be gas. 

damarble
damarble New Reader
12/29/20 9:15 a.m.

​​​​I guess I got featured on Ford Authority so better get serious lol! 

For those that don't know, the 2.3EB is a recycled Mazda MZR, as featured in the 06-14 Miata. 

 

The 6 speed is a little girthy and doesn't shift as well but it stronger. 09+ are smoother and stronger. 

 

The 5 speed has been successfully fit before by others before me. 

 

John Mensch
John Mensch
12/29/20 9:34 p.m.

damarble, this looks like a great project!  Just a month ago I got a similar project running and on the road (a 1999 Miata with a 2.0 Ecoboost).  

In the case of the NB Miata I was able to keep everything "under the hood" to preserve the stealth aspect.  I did have to do a little cutting related to the HPFP, but kept it all in the "wiper tray", and didn't have to violate the people space.

You'll have a few details to work out that I didn't (FI capable fueling etc), but please feel free to ping me, I'm more than happy to share any "lessons learned" if they can help!

damarble
damarble New Reader
12/29/20 10:19 p.m.

In reply to John Mensch :

John, you're a genius. I really hoping to cut under the cowl/wiper tray/firewall instead of the hood. It's going to be incredibly close. Did the slight clock of the NC trans help with that clearance? Do you have a thread anywhere? 

TheTick58
TheTick58 New Reader
12/30/20 8:16 a.m.

In reply to damarble :

I asked to have my "handle" changed so I wasn't always posting with my full name (the is John). 

 

This really seams like a great swap for a small/light car.  To the best of my searching abilities, I think mine is the first ecoboost NB Miata.  I ended up with a Fusion motor ($324 with 73k miles).

I went with the 6 speed NC trans.  With all the torque even the 2.0 makes the 6 speed is redundant, but my understanding was it is stronger than the 5 speed, but I may be remembering NB trans stories.  Get a good clutch too.  I started with a cheaper clutch that "was good to 300hp", and slips in 4-6.  I already have the replacement (a Clutchmaster FX350), but won't have it in till Spring.

I kept the motor "square with the world", and let the trans go where it needed, so the 15-20 degree clocking of the trans affected the shifter location more than the HPFP.  I've had a couple versions of an offset shifter, and have another one to try in the Spring.

Here's a couple pics of the HPFP and the resulting hole.  The hole is bigger than it needed to be because the VIN is in that location, so I cut out the whole VIN and intend to "remount it" to the side (there are other VIN locations on the car).  I intend to build a box to go around the fuel line to plug the hole at some point.

I've been working on the car for about 2 years and have the original build thread on our local autocross forum.  Here's the link, but it has a lot of "local color"...  https://forums.mnautox.com/forum/main-forum/general-discussion/464779-and-so-it-begins-starts-f-r-e-coboost-miata

I have considered transffering most of the actual car working notes somewhere else for a cleaner read.  Maybe I should do that.

TVR Scott (Forum Supporter)
TVR Scott (Forum Supporter) Dork
12/30/20 8:47 a.m.

In reply to TheTick58 :

I've also got a 2.0 EB swap going - 1973 TVR.  I'll likely have questions for you as well.  I'd love to see a build thread.

damarble
damarble New Reader
12/30/20 10:43 a.m.

In reply to TheTick58 :

Thanks. That extra 300cc sure cost me some money. I don't think the 6 speed is going to fit without major work. Maybe I'll buy it first while I'm waiting. 

I found this badass little gizmo. The vacuum pump may interfere with my hood latch so have a backup plan. I don't even have a brake booster, so my vacuum load is minimal. 

 

TheTick58
TheTick58 New Reader
12/31/20 4:08 p.m.
TVR Scott (Forum Supporter) said:

In reply to TheTick58 :

I've also got a 2.0 EB swap going - 1973 TVR.  I'll likely have questions for you as well.  I'd love to see a build thread.

"Ask and ye shall receive"

I had a running build thread on my local autocross forum, but it had a lot of "local color", and I've been looking for a better place to keep the build related contact.  I just moved it all over here, so feel free to look it over!

https://grassrootsmotorsports.com/forum/build-projects-and-project-cars/who-thinks-an-ecoboost-miata-is-a-good-idea/179908/page1/

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