Any update on the setup Jason? Hopefully all things have been worked out...

Found a few things and hopefully they will fix all of this. For starters I fixed all the little leaks that showed up, paying extra attention to the vvt oil feed. Just got back from a 30 minute drive and it appears they truly are fixed. Replaced the trigger sensor since it appeared to have been slightly damaged. My VVT connector wasn't making a good connection, so I tweaked that a bit and hopefully it will stay connected in the future. Put a fitting on my hotside piping to get a signal for the wastegate. My new logs show it holding steady at 14.4# for now. Right now the AFRs are steady between 11:1 and 11.1:1 at WOT.

I'm only going to be doing some fuel adjustments until I can get it tuned. I will find out tomorrow when I can get it back on the dyno and have my tuner work his magic.

Glad to hear that you seem to have a handle on things and are on your way to getting things sorted. Make sure to post your dyno results when you do get a chance to tune it!

Here's a rough tune at 17.5# while running 92 octane gas. Made a lot of progress last night.

I just replied in your build thread actually... Looking good. Glad it came down to tuning and nothing really mechanical. You can post the boost vs RPM plot here if you want/have it. BTW, what kinda manifold are you running on this setup?

I don't actually have any of the plots except the printout that I scanned. It basically went like this.

Foot on floor at 3000 rpm, immediately 1#. Spool, spool, spool, 4500 rpm 17.5#. 4625 rpm, steady at 17# and it fell less than 1# towards redline. I am running a ball and spring mbc that get's a signal from my hot side piping. When I redo the pipes it will be moved to the cold side and a few other changes to get it to spool and hold better.

Not too shabby for the power you are laying down now. Sure it feels a lot better than it did when it was falling on it's face up top. :p

It was pulling hard on the dyno, unfortunately it rained this morning so I haven't been able to make any street pulls.

Meh, it happens... Just really glad to hear that most things are sorted. So this is still on a rough tune if I read correctly?

It's a solid tune and the AFRs are steady at 11.5 all the way across. I call it a rough tune because we could have kept going with both boost and timing.

Ah... Still not too bad for 17 psi regardless. Makes me want to get mine all together and see what it can do. :D

While looking at your dyno graph... I notice the little blip in power at ~4500 then it goes back up after that, I'm guessing that has to do with the 17.5 psi boost creep and fall-off to 17 psi... Correct me if I'm wrong.

wow these are some great numbers... im currently building up my miata similar to yours but i will have a built 1.8 and running the same turbo. cant wait to have mine up nad running

His is a built 1.8L as well... With a larger bore piston to reach 1.9L. Same thing I'm in the process of doing.

i bought my motor already built so i dont know exactly what is in it. but the owner said its a built 95 motor

That's pretty much it. I'm using a Tial 44mm wastegate that's dumping to atmosphere and even with that there's some fluctuations. I think it will smooth out when I source the signal from the coldside and run a little bit boost. There's a few things I'm going to try when it goes back to the dyno.

For starters, we can all agree that a turbo of this size doesn't really like to see anything less than #17 and would be happiest at 20+. Because of this, I may just start increasing boost and leaving the timing low to see what kind of numbers I get. This might prove to be better than running low boost with a ton of timing. Reality is probably somewhere in the middle for a very streetable tune.

Things may also change a little bit once I drive it on the street. I'm still in disbelief that this dyno pull and the dyno day pull were both on the same setup running at the same boost level.

Based on my compressor plot, it appears that 17 psi should not be a bad place for the GT3076R. As it passes through and stops right in the most efficient island on the compressor plot. 20 psi would be good as well... However, when you get up to 22 psi, you are BARELY hitting the top of the most efficient island of the turbocharger. So I would say between 17 and 20 psi is where the turbo would be the happiest, but you should be able to make more power at 20+ psi to an extent. Just be careful, as at 25 psi you are RIGHT at the surge line when you spool up fully. Granted this is assuming that you spool up at 4300 RPM at ALL boost levels, which is not the case. So you will have a little extra cushion from the surge line at the higher boost levels than seen in the plot below.

Plot based on 1.9L, 4300RPM full-spool, 8000RPM redline:
http://thumb9.webshots.net/t/66/766/...9usFplF_th.jpg

We'll see, should be fun to compare and see where it ends up. Before it's all over, I'm going to have more invested in dyno time than I will in the motor build.

Sometimes that's what it takes to get the best out of your car. Just glad to see things progressing regardless...

What comp/turbine housings?