~200 rwhp and a usable torque curve. How do I get there?
 

To start off, I don't have a Miata yet, but am planning on getting rid of my skyline to buy one soon. I am thinking that 200 ponies at the wheels seems like a reasonable number for such a light car. Similar power to my skyline but only 2/3 the weight. And it will be US spec so I can drive it in the states. It probably wont be a daily driver but will be seeing a good bit of street use and some track/auto cross use, nothing too serious yet though.

What would be the best way to accomplish this kind of power while maintaining reliability and driveability? I'm not looking for some $300 e-bay turbo but I don't want to spend $15k converting to a LS1 either.

Am I asking too much out of this motor or possibly selling myself short on the potential? I really dont know that much about Miatas other than they handle great, run forever and I want one.

BTW, I have been working on cars pretty much my whole life (nearly 30yrs) so most labor costs are not an issue with the exception of machine work which I would need to have someone else do.

I'm still NA so take what I have with a grain of salt, but have the same goal in mind for my NB next winter. Many people are doing 200 to the wheels though and say that is about the limit before you need to start beefing up Driveline etc. Dem768 is hitting those numbers and more with his Begi S4, Flying Miata Stage II will also hit it if you are looking for prebuilt kits.

When you talk about DIY, I personally am looking to go the ARTECH Manifold, DP, Exhaust route and a 2850 or something and VBand, Iconol everything. I want to track it and not fix it between sessions.

If you don't want to go Turbo, TrackDog has a great MP62 SuperCharger + Intercooler setup that will get you similar horsepower as well.

Adam

2850?

yuk! he said useable torque curve. Not a flat, miniscul one.


Here's my 1.6L running 10psi vs. a 1.8L running 9.5psi. the 1.6L is running a small cheap T3, the 1.8L running a small cheap SR20 T25:

https://www.miataforumz.com/attachme...ine=1328818785

Very similar turbo/exhaust/ecu setup.


same 1.6L car with a little more boost:

http://www.boostedmiata.com/gallery2...inacharger.jpg


result could be easily repeatable on both setup without spend much money at all. Both produce much more torque than a 200rwhp SC setup could ever dream of.

Acquire Mazdaspeed miata. Put intake and exhaust on said miata. There's your 200whp miata. :p

I keep coming back to the FM II but I'm still not sure if I want to spend that much on that kit. Or if it would be cheaper to build one myself. If I understand correctly, that kit should make 250hp (well over my 200 desired) with minimal additional mods. It would seem to me that there should be something closer to the 200hp range for less. I found the m45 kit on track dog with the FMIC that should produce roughly 200hp for $3350 which seems a little more reasonable for my intended use. I still haven't decided what route I want to take whether it be build a N/A and deal with less power for now but have more to spend on suspension, tires, ect and decide if I want to use F/I later. Or go ahead and build a turbo/supercharged Miata right away and sort out the rest later. I am leaning toward the "N/A for now" option since handling is more important to me over all.

What would be a reasonable power expectation for an N/A car (probably 94-97) with a couple grand thrown at it? Basic stuff like Cams, headers, exhaust, intake, maybe some tuning if I can find an affordable engine management option.

Ok, You have my attention. Any way you could give me a list of parts required to make these work? Is it cheaper than just buying a kit? I am a DIY type of person by nature so I find that intriguing in itself. Any issues as far as reliability with either of these? I might even have access to a sr20 turbo for next to nothing. I could probably trade some skyline parts for it.

Ecu, turbo, exhust manifold, down pipe, exhust, injectors, intercooler with piping, wideband o2, boost gauge. Various fittings and lines.

My God, I apologize for the typo! 2850 is an old router, silly fingers. I'm leaning towards a GT2560R, my apologies brain.

My setup consists of a:

BEGi Cast Manifold
T3 50 Trim Chinacharger (42.2mm/60mm) - $150
Custom BEGi built DP
3" Enthuza Exhaust
Some really cheap CXRacing Tube & Fin intercooler
MS ECU with Rx7 460cc injectors

That's about it.

The 1.8L was a BEGi Stage-1, 3" Enthuza Exhaust, with a T25 of an SR20 he bought for $50. Running MS as well and IIRC the same injectors.


Nothing at all wrong with the FMII kit...the M45 S/C is a POS that I poop on.


Here's the same 1.8L setup I talked about compared to another 94 with the JR S/C running Meth and pushing the limits of his setup:

https://www.miataforumz.com/attachme...ine=1328883900

the turbo was still just running 9psi... That SC is pretty much tapped out, where the turbo setup is incredibly versitile and upgradable. Not enough power, up the boost. T25 running out of steam? Slap on a T28. T28 too small, slap on a 2871.

Turbo should always make more torque and topend if done properly and always win with area under curve.

http://www.boostedmiata.com/gallery2...curve_fail.jpg

another easiliy repeatable turbo setup vs. a rotrex supercharger with extential work done to it.

Buy a Megasquirt ECU from Brain, pick up some new or used injectors of the appropriate size, pick up a new or used reputable turbo manifold, buy a little turbo, a cheap ebay intercooler and some piping, buy or make a downpipe and you are ready. You will want to upgrade your clutch and pp because the stock ones are weak.

forgot the clutch in my list :bang:
they do not like boost for long periods of time, mine slipped really bad after i got it.

How much is the megasquirt? Is it pretty straight forward to use? I keep seeing it come up so I'm guessing it is pretty popular, but everywhere I found it was asking around $800 for it. Is that the going price for it? too much? a good deal? It just seems kinda weird that the little electronic bit would account for almost half the price of the total system. Maybe I'm just being cheap.

It's an important piece of the puzzle. The new MSPNP2 is a damn goo dvalue if you compare it to say the Hydra that FM supplies.

How much should it cost me?

the mspnp2 just came out and is $800. You can do say a diypnp for a bit cheaper at $450+30 for the kit plus whatever someone charges you to build it to spec (~$100)

Brain can build you a DIYPNP for whatever the going rate is or you could buy a MSPNP from DIY Autotune. There is also a guy named Reverent (who lives in Greece) on MiataTurbo.net who builds them.

These choices are all about half the price of a mainstream standalone ECU like the AEM, etc. ECUs are not super cheap because they require a certain number of and proper quality of components for reliable operation. They also take some know-how to construct and operate.

Edit: Brain beat me to the details.

Thanks for all the help with this. I like both of these options. The DIY sounds like it might be fun to try. Anybody have any exp. with the DIY kits? I have plenty of practice with a soldering iron and don't foresee building one to be much of an issue. Is there any drawbacks to using the DIYPNP vs buying a pre-built one? I have never done any tuning on a fuel injected vehicle and This will be my first turbo build (I have played with my my skyline a little and even replaced the engine and turbo system, but it was already tuned when I got it). [Probably a dumb question Is this something I will be able to work on myself or is it going to require a dyno shop to do the work. I am assuming a shop being it will probably be a home made turbo setup that a shop will be needed, but maybe its more straight forward than I think.

The tuning? You'll be able to do it yourself with a laptop and a friend who know's what they're doing as long as you get yourself a wideband o2 sensor and gauge.

There are some base tunes available for common fuel injector sizes that you can upload to the ECU. It will still require some attention but you can get it to crank and run with them. I've got one that Brain built but I'm not the expert. I'm still learning as I go.

Thanks everyone, I looked over Brian's write up on how to build the DIY kit and everything seems well within my capabilities and it should be perfectly suitable for my overall power goals of roughly 200hp and the potential for 250hp in the future (not really solid numbers, just what seems to be a reasonable goal to start with for such a light car). Not to mention it looks like a fun project to take on. So I think I'll probably end up going that route.

Sounds like a good time to start a build thread, and keep us updated on progress.

Will do, but gonna have to get to the buying a miata business first.

lol thats always a bit helpful

oh it's coming, I just have to sell my skyline first.

import it to the US and we will do a straight up trade?

I'm guessing this isn't going to work. :D

ikr

Mine is a 95' gtst. If it were a 96-98 it would still be eligible to be federalized but mine is a year too old. So no way to import it. not to mention you need $30k+ (15k to pay the RI (motor x) and a 15k bond plus import fees, shipping, taxes. also you have to do all the labor and parts yourself since motor x no longer does this) and a mountain of paper work just to get the process started. This is why skylines are so expensive in the US. And to be completely honest, yes they are fun to drive, but they are over rated and parts are really expensive. I could have just as much fun or more for a lot less in a vette or a camaro. (I'd say the camaro is probably the best comparison)

It's funny you say that, I had one while I lived in Japan and that was my exact experience. Overrated and overpriced. It was a decent car, and fun to drive, but not nearly worth the hype.

threadjack:
Time and technology have advances quite far since then. They were quite advanced for their time. The true strength of the car lay in the robust drivetrain and all wheel drive system of the GT-R version and it's ability to handle power mods. But they were heavy and far too slow in stock form by today's standards. We are living in the time of a horsepower and technology renaissance that shades our view of the past. The typical measuring stick on the street in America in the late eighties and early nineties was a 215 advertised horsepower limp dishrag chassis called a 5.0 Mustang. That's about 185whp.

Once a GT-R gets above 500whp, they really make use of the AWD system and are not going to be able to adequately put the power down without it. I've driven a 1991 GT-R many, many spirited miles (belongs to my closest running buddy) and been a passenger for thousands of miles in one. It is one of only a couple of Motorex R32s that were completed by them and federally certified 50-state legal. He brought it back from Okinawa, Japan. It is heavily modified and at 733rwhp it is a handful at times on street rubber. I helped him tear the engine down recently in preparation for moar powah. Those damn things are hard to work on...
/threadjack

I hate skylines. It's so awesome for me to hear from the owner of one that he's rather have a vette, and is planning on selling his for a miata.

My thoughts exactly, If you can pick one up for a reasonable price like in japan where they will only run you a few grand then they are a great deal, I just wouldn't spend the money on one in the states.

Very, true. Mine is a gtst and therefore has the RB25 lump (and it's inherent problems) in it And like I've said before, it is fun to drive and I'll admit they were a great car in their time. And well worthy of the reputation they had in that time. But as you said, they just don't cut it by today's standards (although the RB26 comes much closer than the 25). Yet they continue to get hyped like they are modern supercars. Yeah they are a blast to drive and have plenty of potential, I just think they fall a little short of the hype. Same with the supras, great cars, just not the "be all end all" car that some like to portray them as. And you are absolutely correct, they are a real PITA to work on, Hoses everywhere and no room to reach anything. I can only imagine it is worse with two turbos and an awd system in the way.

Your buddy would not happen to be named Matty and currently living in Germany would he? Matty helped me find an engine when mine needed replaced, he also has a motorex r32 back in the states putting down numbers very close to that.

"The typical measuring stick on the street in America in the late eighties and early nineties was a 215 advertised horsepower limp dishrag chassis called a 5.0 Mustang." ROFL so very very true, we were really selling ourselves short back then.

couldnt afford a skyline if i wanted to lol. when im ready to get rid of my pickup im going to be looking at Mitsubishi Evos, Mazdaspeed 3 or 6, or wrx sti

Don't get me wrong, it's a fun car. It's just not as great as some people would make it out to be. Mine is an R33 GTS25T which only makes roughly 200rwhp in stock form, it weighs over 3000lbs and drinks gas like a frat boy drinks cheap beer. I just think I can have more fun with a miata for a LOT less money. Not really one to care about the car as a status symbol, I just want something fun to drive.

All good choices, I really like the speed3's, great sleepers. A car that looks like that just shouldn't be that fast.

I see brain already mentioned T25 off a SR20, but that would be a good starting point if you're on a budget. You can always throw on a bigger/garrett later. Or start with a cheap china turbo for starters. anyways my advice is pretty much in line with everyone else

diypnp
460/550cc rx7 injectors
fm/begi cast manifold (used if budget)
matching downpipe/exhaust whatever you can find. if you want to get new exhaust stuff, including manifold, i highly recommend ARTech on MT.net
cxracing/godspeed intercooler (or whatever ebay is fine)

my old setup, artech mani/exhaust (3"), tiny cxracing intercoooler, 550cc rx7 injectors, diypnp (made by brain), gt2560 @ 16psi (i didnt want to run this much, but i had boost creep issues....downpipe design was the cause), 14psi should have been right around 250, which is what i originally planned. 99 stock motor.

https://www.miataforumz.com/attachme...ine=1329573831

Thanks for the advice, I really like how you included specific brand names, this will help in my search for parts. Since I am only shooting for 200 RWHP to start with, I believe the parts you mentioned should be very suitable for a conservative tune and still have the ability to push 200 to the rear wheels. Therefore leaving me with a reliable yet exciting to drive roadster, with years of use ahead of me. Thanks a lot.