New to turbo'ing, would like some advice on parts required.
 

Hi,

I have never done anything with turbo's before but I am interested in fitting one to my '94 JDM 1.8. I have been interested since a friend showed me the Greddy basic kit for the 1.6. Now I am all fine with working on the car mechanically (hell I use to own a Triumph Dolomite, british laylands finest ;) ) I am not good at electronical things.

So this got me thinking about doing a full mechanical based turbo setup. I realise this will not give me the best power, drivability or fuel economy but it seems more in reach with my knowledge. I am also wanting to do this as cheap as possible without skimping on things.

I was thinking about using a T25 off an S13 or Saab 9000, they seem cheap on ebay. Then also found a new manifold for it too on ebay. I was thinking about running 5-6psi area so I don't need an intercooler or new clutch to keep things simple and cheaper. Will look at using static timing at 6 degrees.

How do you connect your stock downpipe to the turbo? I haven't come across much info yet on this sorry.

I am a little confused with FMU's, now what ratio would I need, do I just want to go as high as possible? If I did my maths correct I thought all I would need is a 3:1 FMU, though I could be completely wrong. That is with the stock 265cc injectors.

Do I need a BOV or O2 clamp at this level of boost?

I guess at absolute minimum I need a boost guage. Is a wideband 100% needed due to the cost of them, I can't seem to find them for less than £150.

Any help will be greatly appreciated.

You don't use your stock downpipe, you buy one intended for a specific manifold/turbo combination or make your own or have one made at an exhaust shop

BOV - you're gonna hear both sides probably but when they're only like $35US from Ebay, why not?

Intercooler - I would run one anyways, but thats just me. Then again I wouldnt aim for 5-6psi either.

Wideband - ehhh, gray area with 5-6PSI but I'd sleep better at night if I knew what was goign on.

You're gonna need way higher than a 3:1FMU.

Most of the questions you asked are equivalent to asking "I'm just running down to the store, do I really need to wear my seat-belt"

Welcome aboard.

A couple of suggestions:

1) if you're going to turbo your car, forget about the thought that you're going to be staying in the 5-6psi area. It's not going to happen. Many before you have discovered that.
2) Why mess with fueling bandaids? MS is your best option. If you're not too electronically inclined; you can buy the one offered by DIY Autotune. You'll get all the tuning support you'll need for your MS on this board.
3) Forget about a weak clutch. I won't last. ;)
4) a Wideband is imperative. You can buy an AEM UEGO or the Innovate LC-1.
5) Have you looked at BEGI's S kit? Also, if you check this board you'll find an announcement from them for cheaper solutions.

I can't stress it enough; if I were in your shoes, I'd use the MS. The best suggestion would be for you to buy and install the MS while your NA and get comfortable with using it and then proceeding to turboing your car.

BTW, please post your location below your Avatar. I got some hints that you're in Britain and there are some forum members from there who could also assist you.

Pics of your car would be good too.

Your grammatical skills have strangely swayed me from my standard noob-flame reply. Read the DIY FAQ in the Useful Posts section. That will answer all your early questions and give you a bunch of new ones that you can answer individually by using the search function. ;)

not another useless post, heard this shit too many times before just search man/woman.

Note from the Moderator...
 

Browse the forum and read the sticky posts about turbocharging your miata. There is nearly complete "cook book" here:

https://www.miataturbo.net/forum/t4288/

Then, post a new thread in the "meet and greet" section here:

Meet and Greet - Miata Turbo Forum - Home of the turbo Mazda Miata.

and introduce yourself.

Failure to do this will result in people making fun of you (they will) and if you respond with the wrong attitude or lack of understanding, it could lead to being banned from the site.

We like new blood, but we like it to be smart and self-sufficient to some degree. If after some serious research you have some remaining items that you still don't understand, feel free to ask. You may still be made fun of, but at least we'll know you're not lazy.

on that note, Welcome to miataturbo!

SloS13,

Ok I will have a look for a downpipe. Though how hard is it to build your own? I have a limited skill with an arc welder you see.

Rafa,

I have previously seen MegaSquirt, it just seems a bit daunting to do. Though I have just had a read through of the MegaSquirt How to guide on this forum and that doesn't seem too bad.

Savington,

Sorry for seeming useless but I had already read that FAQ and those were the questions I still had. Really I wanted to make sure I was thinking along the right lines from people who have had previous experiences with this, for example highly recommending to goto MS.

y8s,

Will make a thread in meet and greet now. :)

Check DIY Autotune's site. You can buy it PNP with no hassles. Those guys even have a video tutorial of how to ;)

Ahh I would with that but that costs more! I can solder and with the good how to guides available it seems MS isn't too bad to do, especially if I get it working on my stock engine first.

now that sounds like a plan!

four posts and now you're thinking right, good job newb.

Seriously, put effective engine management at the TOP of the list, and start now. Bandaids will inhibit you later, and the cost/difficulty can sometimes approach a good F/IC system.

It will take you a long time to get the ECU/piggyback, wide band O2 sensor, and injectors you need, and a while to tackle the learning curve. So do it now, get comfortable while your motors will still survive at a 14.7 afr.

This is assumed when reading the DIY stickies and such from what I can see. People unfamiliar with turbos won't make the connection. I remember when I first starting looking at turbos in general I said "Why can't I use my cool 5Zigen JDM header?" It's now obvious that is impossible to do, and I would have to sell my header to someone on CR.net.

Perhaps a diagram with the basic components might assist with these types of questions, or an addendum to the sticky. Or not.

My .02.

+ a million to getting MS setup and learning to use it and tune it before turboing.

And as mentioned, you can't just run 5 or 6 PSI. You'll be at 10 PSI a week after you turbo it I promise. I ran wastegate pressure of 7 PSI.......... for three days. At 11 now and I'd like to run more.

lol; I told you so. :)

I was also running 7 psi and went up to 12 psi; just to see, mind you. I never went back to 7 psi. I'm in the process of rebuilding my engine and plan to run 15 psi. I think that says it all ;)

i just gained my hope back in this kid. check out the MS forum and talk to megasquirt members like brain and others . it will cost money but it is 100% worth the money. if you want to build it do it right the first time and you have lots of resources to do it here. give yourself head room. 5psi is pretty lame on a miata but 11 is satisfying with a good set up. good luck

Does the OP have a 94 with a 1.6 or 1.8?
Not familiar with the engine size/year range for overseas.

Please check out the WIKI in my sig


Read through it, you will be happy you did.

First sentence in the OP's post says 94 with JDM 1.8.

uhh lets see.... I don't recall ever hearing of a 1.6 94........:jerkit:

They used the 1.6 in the later models in other countries, and the OP is in the UK. But granted the OP said it's a 1.8. But I know some have NB's with 1.6's.

What they hay. I like my 6psi car. 6 psi with bandaids. Turnkey project. I never work on the FMU cars.

Man, just never turn it up. You will never turn it back down.
I totally understand, a little at a time. Money only goes so far.

Basically, Get a
1. Manifold and a turbo. Sometimes you can get a turbo with a upper downpipe on them.
Then you just have to make the lower section.

2. Make a crossover tube at a exhaust shop,
or with a ebay exhaust kit and silicone couplers. As much as you spend. You should just get the ebay intercooler kit. For real. $120. And you will have the platform for if you up boost. Which will be the first day. You will atleast run 6psi mabe 8psi.

3. Afpr or a fmu. DO NOT USE A EBAY (Chinese) FOR THIS! I had a brand new one that didn't work.
GET begi, jackson racing, vortech, or Greddy. I like used ones. They are cheap, Like $75.00
The begi can be rebuilt for cheap. But only buy a working one.

4. Get a MSD boost retard or a Bipes. This allows you to keep stock timming and it retard in boost.
You can work without it, turn your timming down to 8*. But it kinda sucks.

So ARE YOU GETTING A KIT, DIY, OR GETTO STYLE!

I have been wanting to cut off the tubes to the factory header, and use the flange. and make a log style with square tubing from a scrap yard. I think it would rock for cheap.
Or there is a place in a old post that has new flanges for like $35.

Dang IT RED NECK STYLE! I think I'm going to build one. The ebay mani is cracked everywhere.