mfvt

My name is Mike and I purchased a red 1990 Miata w/ hardtop over a year ago. I bought the car mainly for track/autocross and to work on a car as a hobby. When I got the car it had a poorly installed roll bar and some other shoddy workmanship. Sorry if you were the previous owner, but installing a rollbar that needs around 20+ bolts with just 6 is not what I call safe or useful. Also, the short shifter was barely bolted in so I just replaced with stock one from junkyard and it is back to perfection. Anyways got that sorted out and along the way have installed Illuminas w/ FM springs, FM sways, energy suspension bushings, diy endlinks, ps and ac delete. Currently underway is my turbo project, which I do have most of my parts in. I'd like to thank all of you for informative posts and motivation.

As for the turbo build, I planned it to be very upgradeable in the long run. Was planning to for now sticking with <5psi and later add MS when I have a little more time. I pulled a Volvo 13g from the junkyard (still looking for a 15g or 16t but only only 15g I saw had too much play). Volvo turbos are abundant and cheap where I am so that is why I decided to go this route.

Heres a list of what I have so far:
-Volvo 13G (yes I know, tiny)
-Begi T3 manifold
-JGS volvo T3 flange (using as an adapter)
-ebay IC kit (bar and plate, cxracing)
-Saab bypass valve (I have two extras if interested, also can upgrade to metal forge one later) and block off plate for turbo (I hear stock compressor bypass valves are not too great)
-305cc Supra injectors
-ebay MAF adapter and k&n cone filter from summit
-summit 3" turbo muffler and 3" tubing for custom welded exhaust
-diy heat shielding

Still looking for:
-wideband o2
-saab knock sensor apc unit when it warms up at junkyard

Future:
-bigger turbo
-larger injectors
-MS

Well if anyone is interested I can post pictures once I get this project moving along. I have recently got everything in the mail and am currently working on mounting the volvo turbo to the begi manifold.

mfvt

Forgot to mention drivetrain upgrades. Plan on getting a 94+ rear end and swapping a rx7 lsd in as well as a new clutch.

curly

iTrader: (25)

Welcome to the site!

What are your plans for controlling the injectors while in boost? If you're not going MS right away, you're going to need an auxiliary fuel pressure regulator. Also, you mentioned Volvos are abundant in your area. Where might that be? (aka, put your location in your profile so locals might come help you out.)

mfvt

Fixed the info, thanks. From lurking the past month I was going to try and see what I could do with adjusting the AFM with the larger injectors. Do you think it can still run lean during boost? I am not too worried right now on wasted gas since the car just sits in my driveway (titled as historic). I should be getting a MS closer to spring or summer when I can actually drive the car. Also, from now until MS it will only be driven for testing it out and will not see much WOT.

curly

iTrader: (25)

STOP DRIVING YOUR CAR RIGHT NOW

Your computer has no clue what pressure your engine is seeing at any given time, because in stock form, it doesn't need to know. If you've messed with the AFM, I'm assuming you've removed the black plastic lid. Tug on the throttle cable briefly with the lid removed, and you'll realize that the AFM is fully open with almost any throttle. IT IS NOT MEASURING BOOST. Not to mention it should be mounted pre-turbo anyways, before any boost is made. You've linearly increased the amount of fuel with the larger injectors, however with boost you need to increase the fuel exponentially, more or less.

Again, STOP DRIVING YOUR CAR RIGHT NOW

mfvt

Thanks for the heads up. Don't worry car is still in NA form. Sorry I am new to turbos. I see what you mean though. For some reason I was thinking the narrowband and larger injectors could handle the small boost (<5psi before I MS) and afm adjustment for idle. But I agree with you, I now understand. I didn't want to go the bandaid route so I guess I should start building up an MS.

curly

iTrader: (25)

If you're planning on getting a MS as soon as this summer, then you're right, there's no point in bandaids. Apologies for the yelling, wanted to make sure I got the point accross before your engine became a paper weight. You'll be fine with those injectors N/A though. Keep in mind the AFPR bandaid raises the fuel pressure and turns your 305cc/min@100psi injectors into 350-400cc/min@120psi injectors (random figures, but you get the point). So if you do go MS, you'll still only be able to do 6-7psi on those injectors. More definite answers are in the DIY turbo sticky.