Perfect. Glad to hear from you Pat, I know this thread will not disappoint!

 

You know I got a BW S66 and Artech manifold and 4" exhaust sitting on my shelf. Save yourself some work.

Also I just picked up a G25-550 it will be interesting to see how it compares in spool and top end compared to the big boys you are running.

 

Hey Pat. Good to see you up on here again. Your thread has always been very informing and entertaining. Looking forward to seeing your changes and results.

 

Today I pulled the downpipe/turbo/manifold. Then stared at the manifold for about 2 hours trying to find any way to put it in my mill that didn't involve an elaborate fixture system. Eventually figured I had to build some kind of fixture as the flanges are not 90* apart so clamping on one won't work. Ended up building a pair of steel brackets, bending them till the angle was about right, then bracing it and zip-tying it down. I know, lol bad for my first post on my mill! But hey, it got the job done. I went really slow so I wouldn't throw the part. It was just floating there but I went slow and was able to surface it! Just got it mostly level, then touched off and started take 5 thou off until it was flat. Ended up removing 30 thou total. Turned out good. Next is the turbo flange. +

 

V-mount AC condenser and intercooler, put rad in the trunk?

 

I forgot to mention it, but over the winter, I may also remove the factory front crash support and fab up a tubular one that maintains the strength and all, but gives me more room for heat exchangers. I do want to make some changes on it, to improve cooling. If I did anything in the trunk, it would be a secondary radiator for the engine. Something that supplements the existing one.

 

Ordered a TIG welder! Picked up the latest Alpha Tig, the 201XD. Won't be here for a month or so, but it's ordered. Plans are to build a stainless exhaust system with it. Not sure what other projects, but it will be awesome to have TIG capability. Will be able to do much higher quality fabrication.

Currently planing out what parts I need and getting ready to order everything.

Where do y'all recommend I buy all the stuff to fab a 304 stainless exhaust? Need the mandrel bends and straight tubing. Prefer thinnest I can find, but almost everything I find is 16 gauge.

 

Columbia mandrel for the bends. Unless you want to spend 8 times as much to save 4 pounds, then 20ga from burns stainless.
Also, if you go to a tubular front subframe and don't mind a little bit of the pipe banging on the rear subframe /braces, 3.5" doesn't require cutting the chassis or just some hammering.

 

+1 for Columbia

"I now have a CNC mill so I can fab some pretty cool parts! I have 22" x 6" x 12" of travel, so I can do a good amount of things with that. It can cut steel, aluminum, etc and hit around 0.001" to 0.002" tolerance on a 4" OD."

This sounds awesome. Looking forward to seeing some cool parts being built!

 

Columbia Mandrel is sort of MIA. They are working slow and only selling back stock. Not really sure what happened, but they had some issues starting last summer.

 

Just checked, columbia river is not showing any 3" 304 stainless bends in stock! Or 3" 304 straight tubing. So that's not gonna work.

Leafy, do you think (or did you observe) a difference in anything from 3" to 3.5"? I know you went to it years ago.

 

Thanks! I am sort of looking for something to make with it. Maybe I'll make my own turbo manifold finally, been wanting to try that for a while. That would be a down the road project of coarse but that could be fun.

Besides that, I'm also thinking of a coil pack bracket. Maybe some other random brackets here/there to clean things up.

 

Found this: https://www.maperformance.com/collec...otrod-fabkit-3

That looks like a pretty good deal. Anyone buy from these guys before?

 

Cant hide money...lol..

In regard to 3" vs 3.5" exhaust. Might be worth considering 3.5" at least for first few feet of downpipe with that efr7670. If you follow the formula 1.25 x turbine exducer size that puts you at 3.44" if you have a 70mm turbine exducer. I will say however when I switched from a 3" downpipe to 3.5" and open wastegate I noticed little difference, however my exducer is 62.3 which puts me needing only slightly over 3". Maybe you would see more gain?

 

LOL. Ain't got no money after building the mill! Spent way more than I should have on that thing. Next time, I will buy a used CNC or a new one, the bang for buck didn't work out as well as I'd hoped on building one.

So I will be doing an open wastegate as well. Thinking I'm going 3" for now. There are a lot of options for exhaust parts for 3".

RN planning to go with MAP performance I linked above unless anyone has a better place.

Related to the mill, but I was looking for exhaust cutouts and all the ones I find don't have good reviews for reliability. Thinking I might try to make my own one day. With a mill and TIG, that should be doable. Just need a way to actuate it, which I would probably do a wastegate solenoid and use vacuum or pressure to operate it.

 

FWIW I just bought stainless for charge piping on a non-miata rear mount setup. If I was doing it again I'd be grabbing what you posted with a couple of 4 foot straight sections off eBay.

 

Not sure. I went from 3" on a built vvt motor (8.7:1, 1.9L) with a 6758 to 3.5" on the 2.5L MZR (9.5:1) with a 7163. Its really apple to apples, since the MZR head flows more stock than the best ported BP and makes almost as much with boltons NA as half the turbo cars on this site.

Does silicone intakes have stainless bends? I use them for practically everything else tube fab related.

 

Thanks for the recommendations. Silicone intakes did have tubing! I had not seen that before you mentioned it.

Update!

I bought the bends from map performance as well as the straight tubing. It was cheaper on ebay as suggested, for some reason I was hoping the stuff from Map performance will be better quality.

Also ordered an AEM X series WBO2 sensor to replace my LC2 (it works, i just want the AEM, may sell the LC2), ordered a boost gauge that goes to 35 psi with both an analog gauge, and digital readout built in. Ordered stainless rods, 5/16" to make exhaust hangers. A dynomax muffler. Some 1.75" tubing and bends to dump the wastegate under the car. A 100 dollar transmission dipstick, as my cheapy one is sucky, leaky, and I don't trust its accuracy. And a new lower radiator hose and a 400 dollar new AC compressor.

Off to a good start on parts ordering! Going to call or visit a few local welding supply shops, as I need a bottle for the TIG welder, filler wire, and probably other stuff I don't know I need.

 

I prefer to use 5/16th od tubing for exhaust hangers. It's lighter and easier to bend, and you can crush it flat at the pipe for more clearance/easier welding. And it's easier to tig weld into the tube since both tube require similar heat. And you can put retainers on the hanger with just the barb flaring tool.

 

Well! I wish I knew that before I ordered the other stuff. I may just buy some tubing anyway, your post is pretty convincing.