My EFR Build Planning
 

Started with a 1991. Currently I have it VVT swapped driven by a MS3 PNP running all NB2 sensors and wiring, 725cc EV14 injectors, stock everything else. Basically, I have all the fueling and brain ready to go for forced induction. I've also got a 6 speed with uprated clutch and flywheel, and a 3.6 torsen type II diff. My target is 225-250 RWHP with good spool.

At this point, I believe I'm ready for FI. I just placed an order for the Kraken EFR manifold and full 3" exhaust with catalytic converter, and now I'm planning on ordering my EFR 6258 and cold-side. Specifically, I was looking at:
https://www.full-race.com/store/borg...fr-6258-turbo/ (supercore only with EFR V-Band)
https://www.ebay.com/itm/Genuine-Bor...d47f%7Ciid%3A1

That should give me a NIB EFR 6258 that matches what I need for the manifold for ~$1400 right? Are there any risks from purchasing it this way? These prices do significantly undercut other places I'm seeing.
Also, I was planning on building my cold side from either https://www.siliconeintakes.com/, or just bite the bullet and pay the $600 for the flyin miata intercooling and piping kit. The singular piece nature of the flyin miata piping is appealing, but I don't want to spend that much money.

Current questions/doubts:

• Is my EFR 6258 sourcing not suitable? Is buying the turbine housing separately a bad idea?
• Do I need an EFR speed sensor kit?
• Is the built-in EBC and BOV of the EFR 6258 acceptable?
• I know 2.5" post intercooler, 2" pre-intercooler is the easier route, but what pieces specifically work in an NA if I were to build my own intake?
• I've still got to figure out oil/water lines. I was planning on buying an oil filter sandwich plate, and using home-made AN lines which seems easy enough without any special tools. Is this sound?

I have a good bit of time since there's a backlog on the Kraken order, but I want to make sure I have the right plan and parts picked out before I continue.

https://www.miataturbo.net/diy-turbo...4/#post1536337

Or get the whole turbo for ~1250

Edit, As stated further down that thread, price may have crept a bit, but can't hurt to call?

I'm not really a fan of asking for "special pricing" or anything like that. If it's an advertised price, I'll buy it, but some person posting on forums to contact company ABC for a special discount is a bit too much for me. They'd have to at least be a company rep before I did that.

So you want to mickey mouse a turbo together, and likely not have a proper warranty on it because you pieced it together yourself, but calling up a vendor and asking for the already pre negotiated Miata Turbo special pricing is too low brow for you?

I was the person who setup the special EFR pricing for Miata turbo members when i got my turbo from them. and lots of others followed and purchased the turbos there.

Industrial Injection is a platinum BW dealer, BW corporate referred me to them when i called complaining that i cannot find any EFR turbos in stock anywhere.

If you dont want to make a phone call to save ~$ 200, Full-Race has the complete turbo for $1495. point click, buy. i think $120 is worth the piece of mind that you are getting a whole turbo with full warranty.

Industrial Injections price has gone up a ton. I talked to Gavin a few weeks ago and 6258 prices were $200 more then back in June.

Thanks, I'll make sure to buy it put together. I haven't done this before and assumed the warranty would be unaffected because doing the install may require you to adjust the housing to ensure proper alignment of the fluid pathways. At least, I thought it might. Since you say it's a big risk and I'd be "Mickey mousing" it if I did, I'll stick to buying the full unit.

I'm this case you need to have Gavin price match some one else, a member here had gavin price match jegs.com when they had this turbo for $1190 or so.
They will price match a valid website
Here is one for $1383. Still a good deal
https://thmotorsports.com/10526673-b...0aAr9XEALw_wcB


The super core will have a warranty, but if there's an issue, BW might ask where you bought the turbine housing, and when you say "ebay" they might say not authorized seller and deny warranty. You know how companies get with authorized dealers...

If you are dealing with Full Race, remember they have M8 and M10 inconel studs and hardware for sale for the hotside and they are reasonable.

To answer your other questions

You don't need speed sensor
Built in ebc and bov is fine. I'm using the turbo as it came with 17 psi and 309hp.
I got the medium spring iwg. Gives me 10-11 psi 250hp wastegate only, and 309hp at 17 psi.

Stock bov whistles a bit when cruising around not boosting, a bit annoying. BW sells a different spring to solve this.

My kraken kit came with oil and water lines, has he stopped including the lines?

I am well aware of the price matching. The point I was trying to make is that EFR pricing floats around a ton. We had a member here get a 6258 for about $1190, now Gavin can't do them for less then $1390. Jeggs itself pricing has gone up north of $1700 for a 6258, with a lead time of January last I looked.

$1390 is still the best price around. And gavin has them in stock, unlike every other website that quotes months of wait.

I still think that $1190 pricematch was an error on jegs website, they had the super core price with a full turbo part number.
I see they fixed it now and it's back to msrp of $1750 like it should be.

And in 2+ years, I have never seen jegs actually have anything bw in stock. Always a 2 month wait, then the clock resets again to another wait.

I bought the Kraken kit at the time I did because it looked like he dropped the pricing on it, but unfortunately it looks like he is no longer including the oil/water lines. Inconel studs with copper nuts are still included, but the EFR V-band clamp is not.

One item that's come up: how should I manage engine bay temps?

Should I get the manifold, turbo's turbine housing, and downpipe ceramic coated? I know that'll keep engine bay temps fine, but will that lead to premature wear/warping of the parts? I want to get a setup that will be fine for semi-daily usage for years.

If I wanted to DIY my own heat shield, is there a miata specific guide to follow?

pretty easy to fab up something simple. here are the parts I made. They are ..less simple. also willing to part with them, they dont fit my current system. turbo heat shield, and a big aluminum divider to keep hot air out of the intake, AMAP.

https://cimg2.ibsrv.net/gimg/www.mia...100d46635e.png
https://cimg3.ibsrv.net/gimg/www.mia...ed92e4a29d.png
https://cimg5.ibsrv.net/gimg/www.mia...ba5bd856d6.png

How does that mount? It looks like it's connected to both the turbine housing and the engine bay, but I thought under load those two points can move in relation to each other as the engine mounts can flex.

nothing mounts to the turbine. It bolts to the fender and the brake master cylinder. same with the cold air gaurd, all bolts to the fender in OEM bolt holes.

Awesome. I can make something like that (I think). Thanks.

You can buy the heat shield from FM it fits perfectly with kraken efr setup. I'm running it.

Awesome! It's only $100 and that would make things go much smoother. The less I have to worry about the details, the less likely I am to run into issues.

I ran the FM heat shield and really didnt like it. It mounts to the brake MC and i could feel a lot of vibrations through the brake pedal. It also mounted to the ground strap spot behind the coolant lines which was super hard to access. I sold it and built one myself that mounts to the firewall and some of the mounting hardware from the original airbox. I put some heat reflective tape on, but mine looked like his after putting it together
https://cimg3.ibsrv.net/gimg/www.mia...c82fafc8cd.jpg
https://cimg5.ibsrv.net/gimg/www.mia...a7ac5e98c1.jpg

Thanks for the warning. I think I'll try out the FM heat shield, and if I don't like it go a different route. My main reasoning is I want to do this myself, so keeping complications to a minimum (at least to start) will really help me.

Speaking of "complications", I was looking at intercooler/piping solutions, and found Flyin Miata sells the specific Silicone tubing I want individually (https://www.flyinmiata.com/intercooler-outlet-hose.html and https://www.flyinmiata.com/compresso...oler-hose.html). I know these are flexible so I know it doesn't have to be exact, but would these work with the Fab9 intercooler? https://fab9tuning.com/fab9-intercoo...350hp-capable/ The 2.5" ends work out, but is it safe to assume the dimensions and mounting location are close enough to work?

Yes it will work. It will require cutting the hoses short.

Current plan for oil/water lines:

1. Oil feed:
   1. https://www.ebay.com/itm/MAMBA-Oil-P...72.m2749.l2649
   2. https://www.ebay.com/itm/Hydraulic-F...ss!30309!US!-1
   3. 6AN line created from Braided Stainless Steel Lines, 2x 90° degree fitting + cushion clamps to keep things tidy
   4. EFR turbo comes with 4AN port, but manual suggests to upsize to 6AN when line is > 18", so I'm doing that. Not sure of threading for bearing housing, but once I figure it out, should be straight forward for a 6AN fitting
2. Oil Return:
   1. https://www.ebay.com/itm/Oil-RETURN-...53.m1438.l2649
   2. 10AN line with straight fittings built from siliconeintakes.com
   3. drill 1/2" NPT threads into oil pan, and then a 1/2" NPT to 10AN male-male fitting
3. Water feed and return (I do not currently have a re-route, assuming water hose I'm splicing for coolant is 3/8", will double check):
   1. https://www.ebay.com/itm/2PC-Straigh...WId3QTlsT7t3bQ
   2. 6AN lines from siliconeintakes.com, 2x 90° fitting, one on one end, and the ebay fitting on the other for both lines
   3. 2x https://www.ebay.com/itm/M14X1-5-TO-...MAAOSwHOZcErhW (for EFR bearing housing)

Originally, I was thinking a sandwich plate for my oil source, but I think I'll save a sandwich plate for an oil cooler. That way I can have a thermostat in it and the turbo oil feed will be unaffected. I realize going AN lines for the water lines and oil drain line might be overkill, but since I'm just using the flyin' miata heat shield (or a later DIY one) I didn't want to worry about rubber lines getting too hot or anything like that. It seemed like a safer bet. I also realize all these ebay fittings may be a weak point, but from what I can see they're just raw metal fittings and it's kind of hard to fuck up standardized threads. It's the way I'm splicing into the water lines that has me a bit worried, but the alternative is more complicated with a hose bard to 6AN fitting, then using a regular AN line. I figure making sure I get things right here would prevent a load of headaches down the road so at this point I'm just thinking out loud and hoping someone will correct my stupidity since I haven't done this before. I may be a bit too fascinated with AN lines at this point...

PRL Motorsports sells a Tee that threads in perfectly into the oil pressure sender port on the motor. Get that, it is stronger then the brass ones.

I would also highly recommend looking up hydraulic shops in your local phone book. There are probably some locally that can custom make quality lines. I would not trust anything that is not branded Mocal or AeroQuip myself. I have seen to many cheap AN lines have leaking issues and causing problems.

Wastegate Actuator
 

Which wastegate actuator are you planning on running? I'm planning a similar build and am thinking it would be best to go with the "low-boost" actuator rather than the medium boost actuator it comes with standard.

I'm worried about wastegate pressure being too much for stock internals with the medium can. I want to build my base of an EFR so I have everything in place if/when I decide to build the engine.

I recommend a low boost actuator for stock engines.

My medium boost actuator yields 9-11psi 250hp 225tq. Right at the limit of stock engine.

I also recommend going with the low boost actuator. If you want more power later it is cheap to upgrade to the medium sized one.

Thanks. I had not considered swapping that out, but it makes sense to be safe. It's also only $60.

What's wrong with building my own AN lines? It looks straightforward, and getting someone else to do it will probably add a good bit to the price. The reviews for the specific AN lines I'm looking at are also positive so it seems like a win-win.

As for the T fitting, I was basing it off of Flyin Miata's "bag 4b" and going from there. The threads should all match and be an easy install. I was planning on just using purple loctite as a sealant and nothing else on the NPT and BSPT threads. No sealant on AN threads obviously.

The brass fittings have been known to crack or break from fatigue. A steel fitting, while marginally more is a ton safer. They also offer a 2 port one so that you can wire in a real oil pressure sensor to your MS.

Have you ever built AN lines before? It is not really as easy as it looks in practice. If it all goes perfectly, then yeah they are not bad, when things just don't seem to do what you want it starts to suck. There is also a large variance in quality between brands and price point. All the low priced AN fittings show, and don't work as well. I have used probably 6-10 different brands over the years. from super ebay cheap, same ones you have linked to(I could never get the lines I made not to leak), and up to Aeroquip. When it comes to the oiling of the turbo especially a $1400 one, you don't want issues. Every hydraulic shop I have used does not charge anything for assembly of lines. Generally what I do is go in and tell them what I need. I will have them put one end on the hose the first day, and make the hose a little extra long. Then I will take that hose home, along with the other side fitting. I can then measure lines and mark for perfect fitment. Then I take them back and they finish them for me. I have had hundreds of lines done this way now. I have had a single failure, and the shop immediately made me a new line.

Oil lines are one of the places I just can not see cheaping out on. If there are issues it can cause loss of oil to the motor, or the car being on fire. Spending a bit extra to not have those worries is generally worth the cost.

Many of the ebay stuff takes that as somewhat of a challenge.

Main issues i'd noticed from ebay stuff, regarding threads etc is:

• Threads arent cleaned up, lots of flash left.
• fittings can be off centre (ie: bolt head isnt centred to the threads)
• mating surfaces often arent totally flat
• QC is low, so hollow fittings sometimes end up with really thin walls in spots.
• the metal used is usually pretty weak, probably not tempered correctly.
• There's nit much consistancy, out of 10 fittings 3 may be perfect, 5 may be a bit off, and 2 may be unusable. you dont know which until you've paid and used them.

I'm happy to use ebay stuff for bits that dont do much work, like my catch can, but for important stuff like turbo oil/water lines, i'd really suggest spending the little bit extra, for peace of mind.

Yeap. I've tried 3 diff brands of cheap AN fittings, all of them eventually started to leak. I wanted to believe they would work great, and they did at first, but eventually they start to leak. I've run Jegs brand, summit brand, and some other cheap brand, all leaked after enough use. A local shop has some name brand stuff that doesn't leak and I've been using it lately. Cost more but no leaks!