Hi guys! I'm getting pretty close to having my car turbo'ed so I figured a build thread is in order.

All the images are clickable for 3000x2000 glory

I have a red 91... actually, I have two red 91s.


The left one I got for $500 about 2 months ago. It's a 180k mile with a MAACO repaint and a few small rust spots.

The right one has been my daily driver for the last year, and is the car in my signature. It's a 145k mile 91 with an ebay jdm 94 engine and a 96 brakes and rear end. The 96 parts came from my first Miata that I've totalled about a year ago. It's has a horribly rusty chassis (but straight!) and the worst paint in the world.

The plan is to get the turbo running on my daily, then swap it all on the "new" $500 car, and junk the old chassis since it's beyond repair.

Turbo parts:

• SR20 T25 Garrett turbo
• BEGI log manifold
• 2.5" BEGI downpipe
• Older Flyin Miata 2.5" turbo exhaust with a high-flow cat
• Generic gigantic intercooler, 2.5" cold side, 2" hot side piping
• Bosch recirc BOV
• EBC via megasquirt eventually
• Water & Oil Drain I *THINK* are Artech lines, I'm not sure.

Supporting mods (all done!):

• Standalone MS2
• 14point7 SLC DIY 2 wideband controller
• RX7 550cc cleaned injectors
• NB throttle body so I don't have to plumb the IAC (not like I'm using it... )
• Toyota COPs

Clutch will be an ACT 6-puck with a Fidanza flywheel, once Faeflora lets me rip it out of his car.

Some recent things I've done:

• Clocked the turbo. I read some manual on Garrett site that said to rotate have water inlet lower than outlet, in order to promote water flow.
• Made a wastegate bracket. It's made out of 3/16" aluminium and is STURDY AS ****
• Test fitted everything

Flipped the hard line that goes from radiator to water pump mixing manifold to make room for bottom mount


Installed and wired a 99 throttle body. For 2 reasons. 1) Both TPS and IAC connectors on the side so they don't interfere with the intercooler piping elbow. 2) There is no separate hose for IAC so you don't need to have any extra fittings in the piping.


What I'm missing and still need to do in order to get the car running:

• Add BOV hoses. The Bosch BOV has 1" OD fittings, the silicone intakes BOV tee pipe has 1.25" OD fitting and the BEGI turbo inlet pipe has 1.25" ID pipe
• Tap intercooler endtank for IAT sensor
• Tap oil pan for oil drain
• Route vacuum lines for boost gauge, wastegate and BOV

Stock wastegate spring is like 6 or 7 psi... once I have the clutch I'll add in EBC and run MOAR BOOST.

 

This whole build is made mostly out of used parts.

Turbo, manifold, downpipe, oil drain & water lines - $500
Intercooler and all 2.5" piping - $90
MS2 95% built + misc parts to complete it - $200
Injectors + cleaning - $150 + around $100 for cleaning I think
COPs - like $90? + DIY bracket

In the last week or two I bought a lot of new parts to actually complete the build - 2" piping and couplers, 90* elbows, 10.9 and grade 8 hardware, alumimum stock for IC bracket and wastegate bracket, boost gauge etc... but it's all been pretty cheap.

Here's my intercooler piping. Hopefully this will be useful to someone piecing together a piece.

Cold side is 2" and hot side is 2.5"

Hot side:

• 2 x 2" 2ft 90. One is cut to form a 45", so you can order one 90 and use a 45 instead
• 2 x 2" coupler
• 1 x 2.5" to 2" 90 elbow

Cold side:

• 2 x 2.5" 90 pipe
• 1 x BOV tee
• 2 x 2.5" 90 elbow
• 1 x 2.5" 45 elbow

Intercooler bracket is 3" x 3" x 3ft alumium bracket with some alumium strips. I used 3/16" thick and it's MASSIVE OVERKILL. I will trim the bracket to not block airflow, obviously... and might add another angle to the top part.

 

Some pictures of my $500 chassis that will house all the go-fast parts by spring:

 

Poor man's EGR plug for 99-00 manifold. BEGI charges $27.50 for this plug. Or you can use a Doorman 090055 oil drain plug for less than $3....




It doesn't fit all the way in so I might cut off a few mm to make it a flush fit. But probably not nessesary.

 

Could also use washers to snug up the egr plug? Hmm since it's exposed to exhaust stream though i'd want it to be sturdy snug.

 

I could torque it to like 100ft/lbs as is. The only difference in trimming it or using washers would be aesthetics.

Anyways, we'll see how it works out. I just did NOT want to pay $30 for a ******* bolt.

 

Looks like a great start to your build. I ran a drain plug like that in a manifold for over two years on my last Talon and never had any issues with it backing out or anything else. I used a copper crush washer between the plug and the manifold and torqued the **** out of it.

 

Just as a heads up, we have found that placing the IAT sensor in the manifold/plenum area will get you a more true temp reading. Possibly a thought rather than in the intercooler.

-Sam

 

By accurate you mean exaggerated heat soaked readings?

I'd hope there wasn't a temperate big difference between the IC and valves.

But, in serious, we've found if the sensor is inside the bay, it suffers from horrid heatsoak at idle and after shutdown that causes all sorts of idling/starting issues when using an aftermarket ECU.

 

Maaco paint job looks pretty good, does it look as nice in person? Single stage paint?

 

You've gotta be ******* kidding me.
What the ****.

 

The solution for this is to make sure that the sensor bulb is directly exposed to the airstream. My heatsoak went away when I did this and it reacts instantly now. Yay.

 

Bottom line: coldside intercooler tank = easy way of ensuring correct ait readings. Or somewhere in that area.
DEFINITELY not the manifold though. Any other trickery is just not worth it since the "correct" placement is so easy to pull of.

 

Just put the ******* bulb in the airstream like genius above you says

 

Yeah I'm tapping the end tank for e-z mode. Keep in mind this setup will be on the car for 2-3 weeks tops before I strip the car apart and rebuild it on the new chassis before spring. That build will have more stuff, like trackspeed studs, 99 head, coolant reroute and probably a bigger radiator. I want to track it so, reliability, yo.

Today I did some more work, but no pics till later because I forgot my camera.
Here's a list because bitches everyone loves lists:

• Trimmed the IC bracket so it doesn't block airflow (protip: if you're using a jigsaw, low TPI blades are better for cutting aluminium).
• Got my 3/8 NPT tap. I need to buy a 9/16 drill bit, otherwise I would have tapped the IC by now. 3/8 NPT is same size for IAT and oil drain, btw.
• Bought a radiator hose and used it for semi-decent BOV recirculation hoses.
• Installed a boost gauge. Looks boss. I tapped the manifold for another vacuum fitting because plastic Ts are aids and fail.
• Installed driver side harness. It's a 5 point g-force. I didn't do the nut strap yet so right now it's just a 4 point. Feels good, man.

 

Eh I don't blame then because they were nice enough to put M22x1.5 plug size on the site

 

g g g GUESSS WHOOO HAS A SUPERSICK 9/16 drill bit!!!!!!!

 

Only Mr Sawzall himself could fit an IAT sensor and it not be in the airstream.

I mean apart from leaving it lying in the engine bay somewhere how would it be possible!

FWIW from talking to a respected n/a engine builder, the air heats up tremendously as it slams into the back of closed valves and has to suddenly change direction.

BUT I don't personally see how a plenum mounted IAT can improve anything, it's not like our engines die left right and centre due to improperly mounted intake sensors

 

I believe this, but I'm not removing and tapping my IM to find out if it works better.

 

forgot to answer
Maaco paint job looks fine in person. It has a TON of imperfections up close but I'm not complaining. Also I think the paint is real thin and will probably chip fairly easy.

Also, there is a ton of overspray. Classic red tow hooks, anyone?

I needed it like, last week. By saturday I'll be boosting. And I'm removing your clutch with or without your consent, btw. I KNOW WHERE YOU LIVE