My dyno woes
 

They continue. Fuck this shit in general. First there was this thread:

https://www.miataturbo.net/dynos-tim...-10-psi-67268/

And this dyno chart:

https://www.miataturbo.net/attachmen...ine=1342656433

Clearly showing some exhaust restriction and tuning issues. Artech's full 3" exhaust was installed and holy shit what a difference. This dyno followed:

https://www.miataturbo.net/dynos-tim...e6/#post981892

https://www.miataturbo.net/attachmen...ine=1361513000

I was over joyed, however I seemed to have some slow times at the track (I'm the left lane):

https://www.miataturbo.net/dynos-tim...-4-mile-74258/

https://www.miataturbo.net/attachmen...ine=1375595253

I blamed my neo gens, open diff, and noobness (my ten runs were my first and only ten drag runs ever), however for nearly 200hp, everyone was saying things weren't adding up.

Which made sense, when I went to ANOTHER dyno (#3) and this happened:

http://i414.photobucket.com/albums/p...psadd6c786.jpg

Went from 168 to 184. A huge improvement, especially in the midrange, it certainly helped that the dyno operator actually knew what he was doing and gave me some very helpful pointers. It was also an hour of dyno time, rather than 3 free tunes. My dyno cost between the three visits adds up to $25, and roughly 10-12 pulls.

I did find out that in a huge NW dyno challenge, the 193hp dyno was easily 10% HIGHER than all the other dynos in the area, which should of knocked me down to roughly 173hp. Not sure where the other 5hp was lost from my initial run, but theoretically if I go back to that 193hp dyno, it'll read somewhere around 212.

The very experienced and helpful operator/tuner says SR20s (the car, with my same turbo) run about 225 at my boost levels, so given the fact that I have a shitty stock head and .4 liters less, I'm right on target.

Feel free to criticize, I'm very happy with the results, and yes, I hope to get back to the drags sometime soon.

What was the exact changes between dyno 1 and 2? I understand dyno 2 was full 3" ARTech goodness- was dyno 1 with stock midpipe and exhaust or some other crappy setup?

Dyno #1 was Abe's log manifold, 3" DP, a 2.5" cat, then 2.5" crushed crush bent pipe through a muffler. It was seriously ugly and restrictive.

Dyno #2 was the same, except a 3" test pipe, and 3" mandrel bends through a 3" magnaflow, and very small changes in tune to compensate.

Dyno #3 was the same as above, except with a rebuilt head (seals, seats, and surface, no porting), and a few track days and drag runs. It did feel SLIGHTLY down on power between #2&3, I'd be interested to see compression numbers from my engine.

Sub'd for discussion.

Curly, what kind of shape is your longblock in?

It's been rebuilt to stock spec a number of times. Well, twice. One at 90,000, and then just rings at about 115, currently at 126,000.

Rings at 115 were just cause I had the engine out for a clutch, pan off for a oil drain bung, and head off for a surface.

And these are all estimations, I could be off +/- 10,000 miles, I'm horrible at keeping track of that sort of data. I do know it's currently at 126k though.

Tiny turbo is tiny. I have one too, and it's... small. Honestly these things are okay for 200whp, but don't expect much more even wringing the shit out of it.

Time for bigger turbo and more boost.

I think I see the problem. Only 126K on a '93? You obviously need to drive it more. ;)

I do, it's an absolute DD blast right now, with an ebay amp and silky smooth bilsteins. I need just slightly less humidity and legal registration and I'd be driving it a lot more.

Fireinc, I realize it's tiny, I have always hoped for 200hp and no more, due to my 5spd and stock rods. I was just hoping I'd get closer. I need to grow some balls and go to 14-15 psi I think.

949's clutch and another used 5spd is my next project though, it's whining in every gear except 4th, and even at idle with just the input shaft spinning, it whines. My car sounds like it has a supercharger.

Ahh yess, I feel you. On my 99 motor virtual dyno said I was making 190whp @9psi or so. I really doubt it will make much over 215-220whp even tapped out though. This is why I'm going to be looking into something bigger soon.

dyno #2 should read 12% lower than dyno #3. sounds like they add in tons of correction to make you feel good about yourself.

Punch that bitch to 14psi.

Is it possible your timing belt is off a notch? Savington drove around with an engine like that for a while :)

Im currently building a very similar setup, the car has a 2.25" mandrel bent straight through rear section but will have a 3" downpipe and cat.

Same turbo, same manifold design, same 1.6L everything, it will be interesting to see the results.

Dann

MOAR BOOST is always the correct answer.

I know, after seeing numbers well under the safety margin of 200, I wanted to, but decided since we didn't see a huge gain going from 11 to 12, to leave it. For the road racing I do, it's plenty and my free dyno time gave me an incredible amount of knowledge, 20hp, and nearly 20 ft/lbs.

I know it requires a decent additional investment, but I feel like a 2560 would blow your mind. That turbo really is damn near perfect on a stock motor IMO.

I agree wholeheartedly. Bolts right on, 150 bucks and a tune.

Dann

yeah i don't really like the SR20 t25 on a 1.6L due to the .86 A/R turbine housing.

however, Results seem on par for the boost level.

That's all I hoped for. I don't remember hearing that my 193 was spectacular, so I was worried 184 would mean somethings wrong.

184hp on a dynojet at 10psi with that turbo aint shabby. I've done 187rwhp dynojet pulls at 12psi with a poor tune on a bigger turbo.

That was 12psi, 168hp at 11psi, 184hp at 12psi. I think we got it up to 178 or 180hp on 11psi with just timing adjustments, then went up another psi for kicks.

We actually never reached MBT. The Very Experienced Tuner (VET) said that the power and torque curve were starting to level out, indicating we were getting close to MBT. Without any kind of knock detection, the VET suggested stopping where we were. We still gained around 10-12hp from timing, but there might be a little left.

I have a cat to install, registration to buy, a transmission to replace, a more DD'able clutch to buy and install, a kinked intercooler coupler to replace, better injectors to buy and install, and a working idle valve to salvage and install before worrying about making more power.

And before anyone asks, here is said timing table.

https://www.miataturbo.net/attachmen...ine=1376762964

look at that boost plot one more time.

Ah. So only a little creep at the end, hadn't looked at that. I really should have upped the boost some more...next time.

No one calling you out on rebuilding this POS thrice and not throwing in at least rods (unless you did and my reading-fu is suck)?

I hope to beat this 170ish hp with my n/a VVT motor at least :dealwithit:

Yeah...the $280 or whatever for cheap ebay rods and any machining required never lined up with my builds. In fact, money has NEVER lined up with the times I'm rebuilding. Funny how that happens.

I get that. I'm doing this build on food stamps basically now lol. Just busting your balls.

You think I wanted to be on my third 1.6L block?

You're familiar with the definition of "insanity," right?

You have made no mention on what the car weighs with you in it. Do you have that information?

I'm not a liberal if that's what you were getting at.

:fawk:

:dealwithit:

:brain:

:rofl:

I'm sure you people would like to see smurfy spinning the rollers
Josh's turbo smurf






https://www.miataturbo.net/attachmen...ine=1377039847
Laz

Ah yes, Laz. That damn thing is such a pile, but also such an absolute blast. We've got about ~$1500 total invested in it, and anyone that drives it on track say it's the most fun they've ever had. Highlights are bilstiens, 1900lbs, and a borrowed MS.

Did 109hp with a 16-17afr curve, and 5-6 degrees past MBT. Ended with a safe curve, 1* under MBT, and 115hp.

Oh, and my car weighs 2150 in "street" form, so ditching both seats, throwing in my MOMO Start, and a few other bits and pieces I take out, and I should be right at 2100lbs, plus my porky 180, or 2280ish. That 2150 was with half a tank I believe.

You like punishing yourself?:party:

no, i like a running car...

I offered him a vvt longblock many times but he says its for suckers and "1.6 PHO LAYFEEE!!!111"

:giggle:

His 90hp revs better than your 140. Better for drifting.

I finally fixed this kinked coupler today. $8.50 from Amazon. I reused one I had cut for an old over-the-radiator setup. No idea if it'll help spool or anything, but it's always bugged me and every little bit helps.

https://www.miataturbo.net/attachmen...ine=1377129888

Here's the kinked one, it's worse than this picture makes it out to be.

https://www.miataturbo.net/attachmen...ine=1377129888

Hopefully sooner rather than later I'll be able to go back and see what 14psi does.

I told you to turn up the boost while we were there but noooooo.

Apparently you and Braineack are better at looking at the average boost than I am.

We do that is obvious.
Some pics from our failed attempts at drag racing
This all was pre dyno session 3
https://www.miataturbo.net/attachmen...ine=1377571273
https://www.miataturbo.net/attachmen...ine=1377571273
https://www.miataturbo.net/attachmen...ine=1377571273
https://www.miataturbo.net/attachmen...ine=1377571273