Hey all, first post on Miataturbo so be gentle. Or don't. I didn't see a subforum for build threads so I thought I'd put this here and hopefully get some feedback or ideas for what amounts to a very ill-advised way to spend money and amuse myself.


Here's my garbage.


Here's what I've done so far.


I found this. Not sure what I'm supposed to do with it, but it's cute.

What I've got here is a ridiculously budget built. I'm maybe $200 (if that) into this so far. Stock turbocharger off of a Mitsubishi 3000GT VR-4 (free) with a booger-welded awful manifold ($40 in stainless steel parts), stock 3000GT turbo turndown going to a custom two-piece downpipe made from scrap and $10 worth of gaskets. Aaaand that's about it. I've plumbed up the oil feed, still working on the return but I'm not sure how to go about doing that. I really don't want to have to drop my subframe and remove the oil pan to drill it off the car, but it doesn't look like there's a way to drill and tap the oil pan on the car that will result in the return line being above the oil level in the pan. Because I refuse to do things the accepted way my current idea is to drain the turbo into a large catch can where the frothy oil can cool off slightly and turn back into a coherent liquid, then go down a 1/2" drain line into a custom fitting screwed into the oil drain plug.

My other question I'm not sure about refers to something I read in a forum thread (the most accurate source of information) once and can't find again. Someone claimed that an entirely stock fuel system can handle anything below 5psi of boost, and that they had done so in their daily driver. Stock fuel pressure regulator, stock pump, stock injectors, everything. I'd love to plumb up my turbo to the intake and putter around a bit, even if just on 3psi just to say "my car is boosted, yo" until I have the ~$700 barrier of entry to buy a MSPNP. Does this sound viable? Is there a chance of leaning my mess out and melting a piston with 3-5PSI on stock nonsense?

 

Drill your oil pan on the car. Look up Flyin' Miatas turbo instructions for dimensions on where to drill. Everyone does this, search.

Get Megasquirt now. Well, take all the turbo stuff off, Megasquirt it, learn about Megasquirt, then put the turbo stuff on. It'll be much easier to learn on a non-boosted car. Boosting on the stock ECU is not good, you've probably been reading Miata.net too much.

Also, there is a build thread section.

 

If this is what you're referring to, I'm familiar, and will probably go this route, but I'm still curious about the viability of my much-more-unique-because-it's-stupid oil cooler/condenser drain-plug return line setup. Though, concerning the FM drill location, I can access that just by removing the splash shield and using some sort of low-profile drill, right? I haven't had the opportunity to poke around under the car with the splash shield off due to the car being about 20 miles from my house at a friend's shop.

As for the megasquirt, that's about what I expected for a response, but not what I asked. MSPNP is happening as soon as I sell my Mustang (or shortly thereafter), but I'm curious what the limits of fuel delivery are with the stock setup. There are dozens and dozens of potato-potato-potato megasquirting oil pan drilling turbo setups on this site, but I'm curious about the stuff nobody does because it's stupid, like a turbo setup that makes 10hp, or an oil return line that makes absolutely no sense to anybody.

 

Build Threads - Miata Turbo Forum -Boost cars, acquire cats.

 

Aaaand my first thread on TM is a dumpster fire. This is what I get for not looking hard enough. If a mod's watching, move this thread where it belongs.

 

I mean can you afford to replace the motor when you cause it to explode? The stock ecu cannot handle boost at all. At the very minimum you would need an FMU, O2 clamp, and then retard the stock timing. You don't see any stupid stuff because we have all seen it fail and result in blown motors. Blown motors are more expensive then doing it correctly the first time. You also assume that you will be able to make a minimal amount of boost. The majority of wastage's out there are in the 7-9PSI range. You might make slightly less then that with your shitty manifold and exhaust, but I doubt you get as low as you think you want.

 

You ask about stock fuel system, but then you say "until I have the ~$700 barrier of entry to buy a MSPNP". So this to me means you're trying to run the stock ECU at first as well.

Stock fuel system is good to 160 hp or so. So yes, you definitely can have stock injectors/pump/etc and get it running safely on the turbo, you really only need injectors to get you to even 250 hp (some peoples pumps have made it, some people have reported needing pumps over 200 hp).

Why would we answer questions about a setup "nobody does because it's stupid"? Do it once, do it right. We practice good engineering decisions here, we don't support the "I've got 500 bucks to turbo my car!!" attitude. Running the oil drain to a catch can, which then feeds into the oil drain sounds like extra parts, fittings, clamps, packaging space, weight, and failure points, for something that will gain nothing. The attitude of trying to find other ways to do things is fine, as long as they have merit. By all means, propose a new way to do something, unless your only reason is "because no one does it".

 

Stock system can handle zero boost without something increasing the fuel flow.

My friends had a Voodoo box, 1.8 injectors on a 1.6 (about 10-15% bigger) and when the power for the voodoo box went out (shitty wiring from the PO, currently fix and an ecu going in) it would go lean the moment he made any positive pressure.

Minimum is an FMU and retarded timing, but you have to buy and install a wideband before you can even do that, otherwise you won't know what affect the FMU is having. Search around for a good deal on at minimum DIYPNP, preferably DIYPNP 2 or best, MS3.

I got my MS3X for $460 shipped with IAT sensor and adapter harness off ClubRoadster.

 

There are a few MSPNPs on eBay for ~$699 that I'm looking at. Hopefully one of these people will buy my crap so I can buy crap for my crap. Looks like I'll be waiting until then to drive this thing. I could have sworn that I read about some guy in la-la land running 4-psi on stock fuel and ECU, but I guess that's fiction. I do have a wideband lying around, somewhere, which I'll be using for tuning when I get the MS. After work today I'll get the little bugger on a lift and see about drilling that oil pan. Hopefully I can find the drill bits and taps that I need in my buddy's utter disaster of a shop.

As for tuning the MS, shop-owning buddy and I have built a few supercharged/turbocharged/twincharged/you name it 3800-powered Buicks, but tuning a modern engine is a whole different world than something as old as a Miata. Hopefully our combined lack of knowledge will add up to one reasonably competent tuner. Hopefully. Of course, this same buddy is urging me to emulate his turbo Ford Festiva build he did back in the early 2000s with his engine management amounting to "a collection of vacuum hoses and FPUs" amazingly he never blew that thing up. I actually think he put an adjustible FPU and a rising-rate FPU in the passenger seat of my Miata with the intention of me using them. Doubt I will unless I get really impatient, which is always a possibility.

 

holy tiny turbo batman. even by 1.6 standards.

3800 a modern engine?? more modern than the miata??

do yourself a favor and pull that manifold and turbo off. Get your MS FIRST and then add the turbo. It is much easier/safer to learn tuning on the car with no boost.

There are so many financially reasonable options for MS that it is dumb not to do it.

 

you can also consider Reverant's MS setups. he sells PNP MS2's with basemaps to help you get started. I plan on picking up a MS2 from him.

 

Or he can watch the classifieds on here and find one for reasonably priced. I really don't think eBay is the place to look for megasquirts.

 

I'm looking for maybe 170hp. Not 170hp more than it has now, 170hp total. For that, the Mitsubishi turbo is adequate. Taking off the turbo manifold isn't happening, considering the turbo manifold is built partially out of cut up parts of my NA manifold.

And really the benefits of spending more than double my investment into this kit so far on a MS vs the band-aid approach on a car that will see MAYBE 7psi seem dubious at this point. Sure, it will prevent engine blowing-upping but so could "tuning" the whole setup conservatively and running some water/meth injection.

Of course, if I suddenly come into money all bets are off and this bastard is getting a Fiesta ST turbo, MSPNP, and all sorts of goodies. But until then it's a pointlessly-low-powered cheap ghetto-build. The exact thing you guys hate.

 

to be fair, the build threads are pretty buried... i mean they are under general discussion, then media, then build threads.

 

Maybe it will be fine with bandaids and crap if you port the **** out of the wastegate and permanently fix it wide open. You could maybe run 2 or 3psi, perhaps, you might be OK. Maybe.

 

I sold my ms2 extra on here for 400 bucks. they come up. You've already been told, if you cant afford a used ms, you cant afford a blown engine. Why don't you just build a solid NA car? 3 psi wont do dick, compared to a well sorted NA car with a 99-02 head. **** you could even put some junkyard 03 pistons in it for the 10.0 compression. It breaks every rule of good engine building, but it would be safer and more reliable than what you have there..

 

Yeah, that's some ridiculous organization, but now I know better.

Yeah, I found an adjustible FPU and a rising rate FPU in my trunk, and a buddy came up with some injectors from a supercharged Buick 3800 Series II and a matching fuel pump and a wideband o2. Similar setup he's run on dozens of small 4-bangers since the late 90s, except he pushed all of that far harder than I would ever be pushing this. For my current mild goals that seems fine. My buddy seems wary of wideband sensors, says they seem to always fail him in some way or another after 6 months or so. Can anyone else chime in on the reliability of a wideband setup? Surely for $200 it'll last a bit longer than that.

 

My wideband is more than two years old. MTX-L

 

https://jet.com/product/Innovate-Mot...f8b404786b52ad

That is the MTX-L and is the best for the money easily. Also, you get 15% off your first order with Jet.com and free shipping. So that gets it down to the $130 range.

 

I use the same wideband that I have run for probably a year and a half, 10k boosted on it.
I also agree with Ryan, 3 psi won't do dick. I do have a set of vvt pistons, I don't need though.