95R street car project
 

My daily driver and testbed for new widgets. The goal was to take our completely stock, high mileage and rough looking 95 R package we picked up in 2010 for $750 and turn it into a clean daily driver that should pass emissions testing in every state. The car will be autocrossed and used for HPDE (Miata Challenge) now and then. I was after a very clean, OEM look. No wild aero, pretty stock looking under hood. Scaled out at about 2180lbs with a splash of fuel.

https://www.miataturbo.net/attachmen...ine=1327729301
https://www.miataturbo.net/attachmen...ine=1327729301

https://www.miataturbo.net/attachmen...ine=1328119328
https://www.miataturbo.net/attachmen...ine=1328119328
IMAGES
http://949racing.com/95R/95R_2.jpg
http://949racing.com/95R/95R_engine_bay_1.jpg


Suspension
We fitted Xida-S with 700/400 rates. RB 1.125" #54105 front sway bar. Rear is the OEM 12mm with urethane bushings. Prothane control arm and diff bushings, SuperMiata end links. Diff is the stock 4.1 type 1 Torsen.

Brakes are OEM Sport Brakes with our two piece rotors and XP10's up front, XP8's in back, stainless lines all around with Motul RBF600.

The car has an NB front subframe and depowered steering rack.

Engine
We blueprinted an NB2 motor with Supertech 11.0:1 83.5mm pistons that were shaved down to create 10.5:1 compression. Supertech valve springs, SCAT forged rods and ACL race bearings. The rest is 100% OEM parts. We filled it with 5W30 Amsoil OEM street oil. Since this car has a metal core cat, we couldn't run a high zinc race oil without contaminating it. Exhaust is a custom built 2.5" stainless with a resonator and 16" Magnaflow muffler out back. ECU is a special Adaptronic 440 ECU configured just for this type of conversion. Thread on the ECU here http://forum.miata.net/vb/showthread.php?t=403239

Phase one - Emissions compliance
As an experiment, we initially built the car with an EUDM header and heatshield to retain a full OEM appearance and functionality. We also kept the OEM NA8 airbox and NB2 MAF. With all that OEM hardware and a cat, we squeaked out 126whp on CA91. Guessing another 2-3whp with 93 octane fuel as we were det limited when tuning for 126whp.

Phase two - make a little power
Next we added a K&N CARB legal 57-0348 intake kit. With that kit installed we made 131whp. Next we added a Racing Beat 56008 header and made 139whp. With the header, our emissions compliance went out the window.

We found however, that intake temps were still very high. The culprit turned out to be the plastic crossover tube. Plastic has high thermal inertia. It soaks up heat slowly but also releases it very slowly. Basically it heat soaks and stays hot regardless. We wrapped the OEM tube in foil tape and that slowed the heat soak noticeably. The next step was to replace the crossover pipe with an aluminum piece to try to get rid of heat a bit better. The only CARB legal intake we could find was a K&N 69-6000TP for a 99-05. This kit was a huge improvement in design over the questionable efficiency and safety of the snorkel intake of the 57-0348 NA8 kit.

The aluminum pipe helped a bunch. We went a step further and applied self adhesive thermal barrier wrap to the crossover pipe. Since the Adaptronic ECU doesn't actually use the MAF, we deleted that as well. It hasn't gotten on the dyno with the revised intake but I'm expecting about 145whp which was our project goal from the start.

For now the car has no oil cooler but we'll add a very small Setrab with -10 push on hoses and Mocal thermostatic sandwich plate. Koyo 37mm radiator and Koyo cap with M-Tuned reroute. It runs a bit to cool unless it's very warm out so we may add some block off plates for the radiator like we had to do with Crusher at T25.

Drivetrain
6 speed trans running Amsoil MTG. Clutch is a clutchnet stage 2 for 1.6 (200mm), organic sprung hub. Lightweight 8.8 lb Cr-Mo flywheel. 15x9 6UL's on 225/454 RS3's running about 26psi. I painted the wheels Ford tungsten gray code T8.

Miscellaneous bits
Harnesses are G-Force 5 pt camlocks. Seats are OMP Grip with custom made fixed brackets. Bar is a Hard Dog HC DD. Wheel is a Momo 350mm mod 78, NRG 2.5 QR and Momo hub.

We added V8 Roadsters subframe braces for added torsional rigidity. We'll some E-Code 55/65 halogen lights so we can actually see where we are going once the sun goes down.

John did a partial wire tuck under the hood. The relay box and ECU are behind the pax airbag cover.

Driving it
It's a hoot! The tuning and bit of compression give it excellent throttle response and torque way down low. The gearing and light flywheel let it zip through the gears like a kart. The ride with the 700/400 Xida-S is very firm but not harsh at all. Feels a bit lumpy at very low speeds but smooths out and begins to glide once you start hammering it. Exhaust is a bit too loud now so we're going to try a larger, heavier muffler. Brakes feel amazing. Super sensitive, tons of power. The XP's dust quite a bit but that's typical. That's it for now, I'm headed off to KINOD. SOCM Meet tomorrow night. Miata Challenge round 1 Sunday at BRP. Kind of a Miata thing going on..

Nice write up, looking foreword to hearing more for sure.
How does the extra 20 or so horsepower feel? Have you done 0-60, 1/8 mile, 1/4 mile or anything like that?

Dyno and lap times are the only measurements I make. The rest is of no real interest to this driver.
Stock 95 weighs about 80lbs more and makes about 102whp. This makes about 145whp so more like 40whp gain. It's nothing like a stock R package to drive.

Sounds awesome, pictures aren't working for me though.

Well sh*t, thats even more impressive. How much would these 40 horsepower set a person back?

Any number of ways to find 40whp. I didn't add this one up but you can go through
the first post and get an idea.

It's fast
 

Just got back from Miata Challenge round 1 at BRP. We dyno'd there at the track and weighed it on our scales. 142whp and 2180# with half a tank of fuel. With Rs3's we went almost 2s under the existing lap record. I consider than a full win for the project. Full interior daily driver with a cat and street tires running well under SM records with essentially a stock motor. Really pleased with the way this thing has turned out.

As the title sponsor of the series, I don't run for points. The car, without a fire bottle, was 11.75 pts so just squeezed into Mod. It would have won mod by about 4s and Super Mod by .1s.

Cool, this is the same route I'm going with my 1994 daily driver, but 2550-2625lb with driver, lol.

The extra 250# should be cost you about 1.5s on a typical 2.5mi road course. So running NT01's instead of RS3's and you're still under SM records.

TSE's "Rover" is also a full interior, uns-stripped DD style HPDE car. It's making 130-135whp, 5 speed 4.3, 225 NT01's. We scaled it yesterday too and it's comp weight would be around 2450#. It was nearly as fast as the 95R, doing 2:03.6's IIRC. So still under SM records.

I think Rover still has almost all of it's A/C hardware. So a mildly breathed on N/A build making closer to 145-150whp and NT01's would still get you well under SM records while maintaining some creature comforts.

We figure the 6 speed in the 95R was worth some speed as much as the extra power and reduced weight from Rover.

Bottom line is is doable. Simple N/A power, full interior, A/C, <SM lap records.
Whoulda thunk.

I hate you Emilio. I was perfectly happy with my 94 A package with Illuminas/FM springs that I drive around on the weekend, but now you have me wanting more. I already have too damn many projects.

The car sounds like a very well balanced, capable machine. I'm jealous.

First, very cool concept and execution. :bigtu:

I can't see the pictures here either, but I found the link on M.net. I can see that the engine bay is pretty spartan but no real shots of the interior. I assume the race weight was with no top of any kind? I'm guessing 2180 is about ~100 - 120 pounds light of an average NA8?

Funny to see different interpretations (probably rooted in skill sets and resource availability). Emilio sees "essentially a stock motor" and "simple N/A power." I see "engine swap, built motor and standalone ECU." :)

Actually, what I took from Emilio's post is that there is a lot of normally aspirated power to be found on these cars with some simple bolt ons. Sure, the engine is built for reliability, but that's not where the power is coming from. Clear description of mods + step-by-step dyno results FTW.

Robert, I just gave you some money (thanks for the parts, BTW), so you don't have any excuse. More projects!! ;)

Thanks for the post, Emilio.

How does the car feel in comparison to a turbo car with similar power? I like the idea of being able to build a car one piece at a time. And how'd you get the weight down?

Jealousy consumes me!

There's another example. :)

I'm sure Emilio will clarify, but I don't think he would suggest you will see ~140 whp on 91-93 octane pump gas with a K&N intake and Racing Beat header on an otherwise stock NA8 nor will you see 2180 pounds in a mildly lightened NB2.


I think the beauty is in the integration of all the different elements and the success of accomplishing the original goals of a fun street car that puts down sub-SM record laps at his local tracks (likely with very high durability). :)

Interior is stock. Other that part swaps that save some weight like Xida < OEM dampers, etc. the car has no significant lightening. It's light because it's a R package = No P/S, A/C, C/C, P/W, radio. OEM top. Only significant lightening mod was removing front and rear bumper supports which is about 25 # combined.

FIA seats and brackets are about 7# lighter each than OEM seats and rails. We added V8 Roadsters frame rail reinforcements so the weight savings on the seat is about a wash. Added a 45# roll bar. Stock dash. You get the idea, the car is not stripped or significantly lightened. This 95 R left the factory weighing about 2200 dry I'm guessing. It was just never heavy to begin with.

You'll make the same power with a healthy junkyard NB2 motor, I/H/E and ECU. Falling off a log simple and maybe $3500 total assuming you do the labor. Less if you have some parts laying around like an exhaust or intake parts.

$1200 NB2 junkyard motor
$400 Square top intake manifold
$550-800 ECU
$180 Wideband
$425 Racing Beat Header
$450 Exhaust
$150 Intake, DIY

This sounds a lot like the silver NB rental formula. Nice build, pics broken though.

Yup. Same sorta notion as the old rental but with greater attention to cosmetic detail and overall cost.

MT.net inline images not displaying?
 

Broken links are MT.net issue. I embed images hosted on my server.
img tag - my server / dot jpg - img tag

MT.net vBulletin software saves those as attachments and puts them on their server. Now they don't display. If I re-embed images, they display for a while then disappear. Nothing I can do about it on this end.

I'll embed them here again as inline images and see if it sticks.

https://www.miataturbo.net/attachmen...ine=1328119328
https://www.miataturbo.net/attachmen...ine=1328119328

http://949racing.com/95R/95R_2.jpg
http://949racing.com/95R/95R_engine_bay_1.jpg

Nice car Emilio, I like seeing these NA power builds.

Where is your fuse box?

I'd love to get a square top but those are more than I paid for my VVT engine, lol.

Wiretuck FTMFW! Damn that's clean, makes my car look like a robot vomited under the hood. My OBDII would freak out if I removed all that stuff. Almost makes me want to build an NA...

Ever try imgur for image file hosting?

My hosting is fine. When I inline link my url, MT.net has the vBulletin set up to save my image on their server and rename it. The image that is not displaying is now named https://www.miataturbo.net/attachmen...ine=1327729301

So the display problem is on MT./net's side, not mine. That's why I pasted the raw links in the first post, so folks can click the link and go to my server.

OBD I FTW

So I have a question, purely for the sake of argument.

Is there a reason you're trying intakes that keep the filter on the hot side of the engine over something simple like a 180* bend to keep it over by the intake manifold? Trying to stick to off the shelf stuff? You mentioned CARB went out the window with the header anyways.

Hard to do a coldside with the headlights. Easier on the stripped racecars and NB's.
We looked at it but I want to do some controlled testing with different lengths instead of fabbing something based on guesswork.

Honestly though, the car is good and I'm satisfied. Might be better to just drive this one mess with the race cars.

I wonder if there's any benefit to shoehorning 85.5 mm pistons into the motor to squeeze a few more watts out of it. It's not boosted so is reliability still an issue?

Did you rewire that, or is that just a wire tuck? I really love how clean the engine bay looks. Mind doing a write up if it is just a simple tuck?

The motor was already built for another purpose and 85.5's were not part of the plan. I also wanted to build something within reach of the average joe. This long block make essentially the same power as a imported used JDM motor and those are readily available for $1000-1500 on ebay and elsewhere. For a used USDM motor, one would possible rebuild a shave the head .025 for about the same CR.

Stock is 1839cc, 83mm
This engine is 83.5mm, 1861cc or 1.2% bigger. So 1.2% more power
85.5's would make it 1952cc or 6.1%. Everything else being equal, this engine would make about 7more hp with the 85.5's.

If I were building a motor from scratch for this project I would do the 85.5mm 11.0:1 pistons, fully port-polish the head, chamber and put oversize valves in it. That would be worth another 20whp over what it makes now, so 165-170whp.

No write up, sorry. You cut two holes in each fender and run the wires though. Simple. There is some simplification of the harness since there is no A/C or P/S but it's mostly just a partial tuck.

On a side note, the reason that mt.net saves the images to its server and puts the links to those is so that in the future the pictures are not lost. There have been threads where pictures and diagrams that were important disappeared because wherever was hosting them went down. So hosting the pictures on here prevents that problem from happening in the future.

That makes good sense but it's glitchy. Take a look at the html in my first post and look at what it's displaying.

Ok, I can follow all of it, except for the lack of fuse box. Im assuming it is in the fender as well? How did you bring it over to that side? Ive never messed with wiring in that area. I dont know if there are connectors by the fuse box or what.

Read first post :)

Dunno how I missed that :facepalm:

I see a really nice STB there. So much conflicting info out there on whether these matter on a chassis with control arms instead of McPhersons. Would love to hear your thoughts on that.

Reduces cowl shake a bit, has no effect on handling, looks cool. John liked the way it looked and wanted it in there. As he's the one building everything here, he puts his stamp on things like that. I wasn't digging the Cusco blue mounts so asked him to shoot those crinkle black.

To make any noticeable change to handling, it needs to be massive like the OEM steel braces or maybe the burly Tein STB for the NB's. Mazda added the braces for NVH reduction.


https://www.miataturbo.net/attachmen...ine=1328290182

I thought those had a negative effect on handling on NAs?

If some told you that at an event or meet it's false.
If your read it on the interweb, it's true.

That seems backwards, but since your telling me that on the internet it must be true...

My predecessor.

I doubt that a typical shock tower brace on a Miata has adverse effect on handling. Not something I have ever experienced. I get a kick out from hearing these rumors of dubious origin.

I saw the Tien on the silver rental a while back at MRLS. It intrigued me so I kept my eyes open. I managed to snatch up a used one on the local forum for $45. I was running frogarms + HT + HDHTDD and the addition of the Tien STB made a noticeable difference. Of course, some assmonkey at either the exhaust, alignment or clutch place crushed my passenger frame rail flat with a jack. Now everything squeaks on that side. FML :facepalm: Hopefully I can 'massage' it back into place with a BFH and get a pair of FM or V8R frame rails to fit.

Did you loose any ground clearance with the V8R rails?

Noticeable difference in what specifically?

Frame rails have bolt heads.

Tits! Going back to last yeeeeear... Now!


ahhh :(

My driveway is super retarded, I have to take it at a pretty drastic angle or I risk scraping. Before the 'burly' stb, I could almost balance the car on the pass front and driver rear while on the high spot, drivers front was at full droop. Flex was bad enough that the dome light would come on. After the Tien, it stopped doing that. Then after the crushed frame rail, it started doing it again. Not exactly scientific, but there was definitely an effect. I need to raise my ride height regardless.

I figured the bolt heads for the frame rails were far enough up against the floor pan that they wouldn't affect ground clearance?

Ah yes, bolts are on the flanges so maybe 1/4" for the rails themselves.

Maybe a bit OT, but I've always loved the orange on this car... if it wasn't for the corky romano thing, lack of time and my laziness (mostly laziness honestly) I would totally rock an orange miata.

I would make it into the general lee. Coincidentally, they Realtor showing the house across the street was driving a "general lee" Lotus Elise, without the confederate flag.

In car video
 

I need to drive more like you. Posted-up, relaxed, almost like you're enjoying the track.

I likes.

it does look like he's is out for a sunday drive, not a care in the world.

How tall are you Emilio?

6-3

I heard you were at CVR this weekend, but never got a chance to say hey. How did this car end up classing for TT?

D, dyno classed. Won both days and won the UMS Tim Attack class A, would have placed 3rd in the higher horsepower C class. 2:01.89

Why don't you take a book or something with you when you're tracking that car so you don't look so bored?

Wow.. what a clean engine bay..

What diff are you running? LSD wise. i think the FD ratio is listed.

Everything in the car is stock unless otherwise specified.

This is Robert in the blue Miata. Good meeting you and getting some insight on how to drive. Wish I could have seen those lines before going out there. Some of the turns you take a totally different line, like hugging the inside on 4and the bowl.