DemkoG

I introduce myself over in the beginner section and my thread started to get long so time to start a build thread.
A little back story on me, I am a long time car builder but have never played with turbos, except for a stock 93 rx7, and this build is going to be my introduction to turbos. Also my first time really doing too much to a 4 cylinder always been a V8 powered guy. I just did not seem right to do that to the sunbeam though.



I have owned a 2001 stock DD and co-owned a 1994 track day car. I enjoyed both of those cars and thought the motor and Trans would be a good fit for my next project, a 1964 sunbeam alpine. Having fallowed the rules for racing I always was envious of the guys that did not have to and made a lot more power.
This is how things stand right now, I have a 1999 stock California motor that has 80k miles on it compression is good and is real clean. No a/c or PS. Thinking about keeping all internals stock. (Outside of the exhaust and ecu is the cal Miata any different?)
And its matching 5-speed
I have gone thru a lot of builds and I think I have a general Idea of what to do, but still plenty of questions




Still has honing marks ca't see too well from the pic.



All bearings were in spec with the plasti gauge no scoring may throw a new set in any ways

The sunbeam is smaller than a Miata and was looking at doing just water injection no IC (I know you leave you self open to failure but I just don’t see any room for a IC.
The sunbeam has been sand blasted and is in primer waiting for the engine bay modifications to start.

My power goals are 200hp, and very street able/quick spool up.
T25 sr20 looks to simple and cheep for my goal. It has a integrated waste gate. I am Still open to suggestions. I am going to try to keep it somewhat affordable.
Mega squirt seems to be the preferred engine management on the forum and open to learning a different tuning program (I have hptunner for LS motors and have done 5 motors).
Looks like the rx7 injectors.
Thinking on keeping stock coils & colder plugs.
And custom turbo back exhaust.
I will take all suggestions thanks for reading threw my first long post. And thanks for your help.

DemkoG

I ported and polished the intake and throttle body trying to get good throttle response the variable intake runners are going back in with bull nosed valves.



I did a little more work to them after this.

shuiend

iTrader: (24)

Go with the newer EV-14 injectors that nigelt is selling. Best bang for the buck out there. Go with an MS3X for the ECU. Worth getting the newest with the megasquirt. Sr20 t25 will work perfectly for the power goals you wants.

Monk

iTrader: (3)

Don't use RX7 injectors. The technology is old.
AidanJ is selling a set of RX8 injectors that are much better.
https://www.miataturbo.net/miata-par...cleaned-83474/
Or check out the GT500 injectors that are popular now.
Flow matched GT500 Injectors

Edit: Lars beat me to it.

3rdCarMX5

iTrader: (1)

This may be a case for a water to air Intercooler. You may not be able to fit a large al Intercooler core but I wouldn't rely solely on water injection over a radiating charge cooling system. Water to air isn't great for miatas due to how easy it is to use an air to air Intercooler but they still work.

Monk

iTrader: (3)

Here is the best I've ever seen:

Thing is awesome. It took a lot of fabrication though.
He's also using an SR20 turbo... on a 1.6... and made 243WHP on the dyno.

DemkoG

Wow so much so quick. Sorry for got to edit out the rx7 injectors that was discussed on the first go threw. I will have to look at the water to air.

hear is some one else that put a 1.6 in theirs to give you an idea of space.

Monk

iTrader: (3)

Wow. That is tight. K good luck.

M.Adamovits

That is tight, though if you're using water to air, where are you putting the exchanger?

Seems to me that there may be space to go around the rad to an intercooler in front of the rad, as per the norm..



I just can't picture where you'd put the water to air system anyways..

Monk

iTrader: (3)

I thought that too at first, but it looks like the grill bars are right up against the rad on the front side.

You might have just enough room to mount it behind the radiator down low. It's not optimal, but it might be your only option.

DemkoG

Yep I have looked at it for a while and the only place I can see putting a IC is in the above pic is blow the bumper behind the license plate area. Cutting into the the lower valance. but then you have a IC just hanging out the chin of the car. I don't know if i like that exposed ans visible like that.

and if a turbo is going to fit I don't know if it can be a cast unit with the turbo in the middle but has to be further forward. that way it dose not interfere with the steering witch happens behind the motor. I am ok with cutting the inner fender to make room.

Once the motor gets settled in I will be looking for a cheep Sr20 t25 (blown) and a ebay exhaust manifold to cut up and see if I can make it fit.

3rdCarMX5

iTrader: (1)

You can find your own way, but I can easily see an inline core on the drivers side next to the radiator and you can tilt the radiator back a couple degrees to slide the radiator in front. They are usually very thin and pretty compact. It is also difficult to see how much space is under the hood, but that is another way to go. But, it looks like you are going super budget build and the A/W intercooler will be expensive.

Girz0r

iTrader: (1)

With it so tight I'd be surprised to see a turbo setup period.

Good luck to you sir!

DemkoG

I am not far enough to say one way or another how it is going to work out this are all just ideas and speculation at this point and I appreciate the ideas. Can u imagine they did shove a small block ford in them. now that makes it tight. one of the reasons why I am not pulling the motor completely apart is if the turbo Idea dose fall I can go NA and build the motor more like this one.
http://forum.miata.net/vb/showthread.php?t=496172 and get close to my goal.

I am not necessarily trying to be budget on the build but there is no reason to go crazy on things for 200hp the t25 sr20 seem to be the a good choice for my goal if I am missing a better option pleas let me know. I am new to the I4 and turbos. I have also learned over the years to start conservatively because projects seem to grow very quickly with speed parts.
My 1988 grand wagoneer with a ls6 in it. was supposed to be a clean up project now is a full on rotisserie restoration with 430hp



The car is only going to weigh about 2000lbs and is not a track car and is only going to see maybe 3000 miles a year so budget is not what comes tom mind but building it to its purpose as a Sunday driver.

sharkythesharkdogg

Maybe get rid of the coil pack and sit the motor further back?

Maybe some kind of side-by-side radiator/intercooler since you said won't be driving it super hard.

That looks pretty tight.

DemkoG

After doing more reading I was thinking about doing the cop mod, to shorten the motor a little and I think if I can do a long short one, not the best for pressure drop I can fit it behind the bumper area.