Need Fuel Management Info on NB
 

Im planning on putting a td04 turbo in my 1999 Miata and running about 8pounds of boost. As far as intercooling and turbo plumbing and set up goes I have all that figured out, but my major issue is fuel management. I thought I would just put in a high pressure pump and a regulator in but then I found out the 99+ is a returnless system.... What do I need to do to make sure that my car runs rich enough after boost? I'm fairly new to mods and fuel systems so make it somewhat simple please.

Megasquirt.

I highly doubt you have anything, at all, "figured out".
You need to learn how to properly turbocharge a car, and how it all works.
Please do so before you ruin a Miata.

Why do you think I'm asking for help then, hotshot? If I knew how to properly turbocharge a car I wouldn't be on the forum. This is a place for DIY help and support. Obviously I need help, and everyone has to start somewhere. Your negativity really isn't helping me now is it?

Anyway I'm not really looking for just info on an ecu system. I was planning on doing just a simple chip and tune but if worse comes to worse and I have to get a whole ecu I would go with megasquirt but you know... College and project car money don't really go hand in hand. So I'm looking for information on like regulators and injectors and whatnot. I'm going to put in a Walbro Fuel Pump 190LPH-HP but the returnless system has me stumped on regulators. I was going to do a rising rate begi one but I can't because the pressure is MAP independent

There are no simple chips to tune. There are no regulators that work well. MS is the cheapest and easiest route to go.

So you're telling me that with the walbro pump, bigger injectors, and a megasquirt with a proper tune I'm good?

You don't even need the bigger fuel pump. Stock is usually good somewhere in the 200-240whp range.

FlowForce EV14 injectors from TrackSpeed Engineering are the injectors you want.

A MS3X of some variant is what you as an ecu. You can get one from Braineack in the for sale section, or from MSLabs through Trackspeed engineering, or from DIYAutoTune.

The ECU is going to be your golden goose of your entire build. Everything else will be moot if you go about things ass backwards like a mr2 in the rain.

You don't want to 'chip anything, BELIEVE ME.

If you don't want to do anything but just want some boost, a FM kit with a voodoo box is your best bet. Shiuend may have to confirm if that bandaid would work.

If I were you, I'd pickup a MKTurbo setup and go from there. Some sort of ev14 injectors that will work with the ecu you choose.

we don't chip our cars.
it's not 1985.

well, begi still does. but they are still living in 1985

we're not gonna spoon feed you here. the expectation is that you'll use the forums search function to learn the basics. if you don't, you're gonna have a bad time.

welcome to the thunderdome :)

Would an MSPNP2 work? Thank you for info on the injectors and pump. That actually saves me a lot of research. I have a td04 with boost controller, bov, all necessary plumbing along with a 28x7x2.5 intercooler. We're doing custom exhaust (including manifold). Just some background for you guys. And before you ask, the fab work for exhaust and all that won't be done by me. It will be a professional hookup I have.

yep, mspnp2 should work no prob. it will also need a wideband and gm iat

I have the wideband already but for the air temp would this one work?

https://www.diyautotune.com/product/gm-open-element-iat-sensor-with-pigtail/

yup that's the one

Be sure to put it in the coldside end tank of the intercooler for 99.99999% less fail and heatsoak.

Alright I think I got everything I need. All in all I'll have those EV14 injectors, mspnp2, IAT sensor, wideband O2 with gauge, boost gauge, boost controller, bov, td04, intercooler, stage 1 ACT clutch, custom exhaust and all that, and probably another oil pressure gauge to make a solid 3 in my console. Sound good or am I missing anything?

Oil lines, possibly water lines if the turbo is water cooled, but that's all I can think of. Every megasquirt I've bought has come with a GM IAT sensor, so you can probably hold off on buying that since it'll most likely come with one.

nope. we just bought mspnp2 from diy for another buddy of mine doesn't come with one

I'm sure you can add it to your order tho

You left out tapping your bung hole. You are definitely going to need to research that. If you tap it wrong you will be very upset.

I caution you on that large of an intercooler if you are keeping A/C. I have same car, same turbo, 2.5 x 5.5 x 27" I/C. The I/C fills the opening completely and blocks airflow to the radiator. The worst case is 100*F+ days running A/C at 45 mph, not even in boost. Sustained boost also will make engine run hot (no A/C). Hot means 230*F and rising. I have not yet done coolant re-route. Unfortunately, I don't have a recommendation on a smaller I/C, as it seems this size range is quite the norm. However, I can say that, at that boost level, a quality unit (can be had from eBay) in that size range is plenty enough, so I expect a smaller one would be OK.

Sixshoother has had similar issues with his NA, and has cut away some of the inner bumper. I thought I'd do similar, but not sure yet if that will help on the NB.

On fueling, what the guys said above.

EDIT: Doesn't look like there are smaller choices available, and you already have your I/C, so just be aware of the over-heating possiblity and the need to get some of the airflow to bypass the I/C.

I also had to move the intercooler back away from the bumper mouth to allow more air through it and around the intercooler. If you try to make it all go through the intercooler the car will overheat.

Yeah, if I had realized, I would have tried harder to relocate the A/C drier. That is what pushes the I/C forward into the mouth.

Would it be possible to fabricate some sort of air scoop to fit underneath the "mouth" that will push/re-route air up between the intercooler and radiator? I live in Phoenix so overheating would definitely be an issue. If no one has tried that solution I guess I could be the first to give it a try.

The first thing you need to know about the Miata's cooling system is that it's a defective design from the factory.

The engine in the Miata was originally designed for FWD applications, and as is common in most vehicles, had the thermostat on the flywheel-end of the head. When Mazda turned the engine 90° and installed it in the Miata, they moved the thermostat to the front of the head. This had the effect of allowing quite a lot of coolant to bypass the majority of the engine when the thermostat is open, and cooling performance suffered.

The common solution to this is what's popularly known as a rear-thermostat reroute, where the thermostat is moved back to the rear of the head where it belongs, the front outlet is blocked, and cumbersome plumbing is added accordingly. If you search the term "reroute" on this forum, you'll find plenty of information.

It's quite inexpensive to fix this problem using mostly off-the-shelf parts, but if you're lazy (and I assume you are), a number of off-the-shelf kits exist to help you, such as: Miata Coolant Reroute System This is the single best cooling upgrade you can do to a Miata.

Besides that, aluminum radiators are pretty cheap, and yes, you can buy a scoop of the sort you describe from Bell Engineering: BEGI Miata turbo Air scooper

With a rear-therm reroute however, you probably won't need it. I used to live in SoCal, and have driven from San Diego to Phoenix and back several times in summer in a turbocharged '92 Miata. So I'm not BSing you when I say that a rear-therm reroute, plus a cheap aluminum radiator, is all you need.