Dyno Result
 

I finally got my car dynoed at a dyno day. My car is currently running:

STOCK EXHAUST!!?!?!?! OMGzzzz
Devil's Own Progressive WI
GT2554R
MegaSquirt 'N Spark
Ebay stg 3 clutch
bunch of other shit that doesnt really matter....


I dynoed at 15psi. It held at 15psi to 5k RPM and dropped to 14ish psi. My timing advance in boost is a constant 14deg above 8-10psi. Below that it is greater than 14deg. I started losing power with over 14deg so that is why I stopped there. My intake temps with the water injection are never greater than 77deg F at 54.46deg F outside temp. I expect that the stock exhaust is robbing me of at least 25-30HP and is probably the reason for the decline in tq above 5k RPM.

Also note that the afr reading on that graph is off. The wb they stuck in the tailpipe kept getting rocketed out the exhaust because of the extreme pressure. I datalogged all my runs and my afr's are a perfect 12.2-12.5 at all times.

thats one flat A/f ratio.. very impressive!

I wish i drove it with 15psi vs the 5psi. Looks great! https://www.miataturbo.net/forums/im...es/bowdown.gif

Post up your AFR datalog, I'm very curious for obvious reasons. You're making me want to hurry up my rear-end conversion as quickly as possible.

For stock exhaust, that's amazing. I'm sure their sensor kept coming out of the tailpipe because it's practically a plug for the stock exhaust. :gay:

lmao...impressive

what manifold dp..?

anybody have any idea what he'd make w/ say 2.5" exhaust, no cats? ;)

With a larger exhaust you will pick up a ton of power. The stock exhaust especially @ 15psi is choking power off really badly. Good numbers though.

nice numbers.....oh to be at 15psi!!!!!

nice numbers yeah next time drop the exhaust at the cat and give er a go WI seems to be sorted very nicely, Where and how did you get your ait numbers from. Also with cooling going on like that you need to try for 12.5-1 or more instead of 10-1 this is probably costing you alot of power lean that bitch out and youll be 200+ easy still good job.

someone didn't read. :gay:

Doh well it did seem something is holding him back maybe the timming is to conservative i dunno he certianly has alot of room to play with it.

i tried more timing and started losing power, thats why I didnt add more. You're right though, I didnt even think about just dropping the catback.

where's that AFR datalog Brian?!


Sidenote: Got the diff pulled apart for the LSD swap! Waiting for the meatball to arrive.

I know but maybe it is in the rate or rpm specific us oems have a point at peak torque where timming scales back a few degrees and then continues on, perhaps this isnt a totall timming issue but an issue of rpm specific timming at one point or another inhibiting your totall power the 2554 is a small turbo but still i expect more at 15psi, esp with a MS. I dunno then agian is the shop you used reliable, and have you dealt with them before dyno setup can efect your results by 30+-%. How did the car act on the dyno was it laboring excessively.

I told that guy to give me a paypall and i still havent heard from him i hope he calls back soon :(

I too would expect more power @15psi, but he did say it had a stock exhaust...and thats gotta hurt a LOT. I would expect it to make like 240ft/lb though so its way lower than normal.

I think the exhaust will also help a lot with spool/area under the torque curve as you spool really late for a gt2554r. 150ft-lbs by 4k rpm is about what my GReddy does and the gt25 should spool waaaay earlier. Bigger exhaust and that setup will be kick ass (not that it's anything shabby right now). :)

Nice numbers. With exhaust it's gonna be nasty!

I'm guessing we'll get to see the post-exhaust dyno to see just how much it'll help. Sweet.

You're spraying water not meth? Curious.. Amazing what you're able to do with the water at any rate.

The stock exhaust is a 1-7/8" IIRC.... that's pretty damned small.

Its wiper fluid, so yes there is methanol. I didn't mention it specifically cuz I thought it was implied. On a second note, I'm now having some difficulties. My WB is reading that I'm rich now for some reason, so it either needs to be recalibrated, or the high loads of the dyno and the high duty cylces I have to run at high boost cleaned out my injectors. Also I was just making some passes down the road to give scott his afr logs and now apparently my pcv valve is bad cuz Im spewing oil out of the front driver side breather. Also my oil pressure gauge is going NUTS in boost which is probably correlating to all the oil on the bottom of my hood and all over my turbo. So I need to sort a couple things out before I can tell you all for sure whats up.

Looking back on my logs from the dyno though it looks like my logs got consecutively more rich, yet the maps I tried only changed timing and not fuel. I dont have any exhaust leaks before the WB sensor either.

maybe you are PIG rich and your WB02 has been showing an improper reading. Are you running a restrictor for the oil feed on your turbo?

Its ball bearing, the restrictor is build in. The turbo is not leaking any oil, I could plainly see that the oil had been coming from the breather. Also, like I said, I havent changed my fuel maps in weeks becuase they were dialed in. Now all of the sudden im getting rich readings. The power feels the same, and I dont get that nasty cloud of "rich" smoke out the back.

welcome to the spilled oil club.

well if the opg goes crazy that means silent knock. you might be 10-1 now and overfueling and knockingt he motor. something isnt right maybe the dyno operator had the laod set to high and it broke something in your motor. :dunno:

I'm feelin pretty iffy about my motor now. I pulled the plugs and they look ok, but there is a distinct stutter while driving now. Also if I get on it even a little I can definately smell oil. The plugs arent wet though so I dunno what to think. Maybe headgasket!?!?!?! How much do leakdown tests cost usually? I dont have a gauge.

maybe you blew a oil seal on the turbo like i asked before how did the car react to the dyno that operator might have blown your shit up or at least sideways

I really couldnt tell you how it "reacted". I've never dynoed a car before so I have nothing to compare it to. Nothing seemed to go wrong or anything. I dont see how the turbo could have a blown seal, it has a restrictor built in.

Well look at it this way the dyno puts a variable amount of load on the motor. if the dyno operator had the laod set up to mimick a say 3K lbs car instead of a 2.6K lbs car is a big difference. And the aditional strain of trying to move 500+lbs more than it would have ever done on normal circumstances could adversly effect the motor, and might blow the turbo is the motor is trying ot do work down low it is barely capable of doing. But if the car did not bog and stayed smooth all the way up then the problem could be else where. I have said it before and i will probably say it agian. It is very difficult to diagnose from x miles away. GL man.

Also, the Garrett ball-bearing turbos might have a restricted opening in the oil-feed to the CHRA compared to a journlal-bearing turbo's inlet size, but that doesn't mean it's restricted enough for every possible application. That's why you see companies like ATP selling additional restrictors for cars in which the oil feed is still putting too much pressure into the CHRA.

yep....its possible that you are blowing oil past the compressor or turbine seals and thats where the oil burning is coming from. Take off the inlet tube and check for oil, also check your PCV and make sure its venting. It is entirely possible that you have excess crankcase pressure and thats why you are spewing oil out the breather...lots of things can cause that. A bad HG can, bad rings, and a bad PCV... good luck.

I talked to Brian yesterday and he just replaced his PCV valve. I think that was the problem. hopefully we'll know more info soon.

From Garretts site:

"Ball-bearing turbochargers can benefit from the addition of an oil restrictor, as most engines deliver more pressure than a ball bearing turbo requires. The benefit is seen in improved boost response due to less windage of oil in the bearing. In addition, lower oil flow further reduces the risk of oil leakage compared to journal-bearing turbochargers. Oil pressure entering a ball-bearing turbocharger needs to be between 40 psi and 45 psi at the maximum engine operating speed. For many common passenger vehicle engines, this generally translates into a restrictor with a minimum of 0.040" diameter orifice upstream of the oil inlet on the turbocharger center section. Again, it is imperative that the restrictor be sized according to the oil pressure characteristics of the engine to which the turbo is attached. Always verify that the appropriate oil pressure is reaching the turbo.

The use of an oil restrictor can (but not always) help ensure that you have the proper oil flow/pressure entering the turbocharger, as well as extract the maximum performance."

Unless they have a 224xLC it is an inertia dyno so I doubt that the load parameters are an issue.

As for the AFRs changing it could be that the sensor is degrading.

You can make a leak down gauge pretty cheaply with a few parts from Homedepot and an auto parts store. Just put "how to make a leakdown gauge" into a search engine. You should also do a compression test. You need to determine why the oil gauge is going nuts, is it blowby or a cracked ringland or has the PCV just taken a crap and boost is pressurizing the crankcase.

Cody (www.lovefab.com) actually added a restrictor to my GT28 inlet which he didn't tell me about until later, but he knew it would need it. Do you have any pictures? Buy a compression gauge, its worth it, anyone buy an ebay one?

New pcv valve didnt cure the problem :(

Just checked, there is no oil in the intake path at all. It is all blowing out of the breather and burning off on the manifold. What can I do to differentiate between a blown hg and a cracked piston. The car sounds like it is running fine for the most part now and it only ejects oil in boost. I'm gonna unhook the wg actuator for now so I cant boost till I figure it out. Fucking dyno....

Doesn't a blown head gasket suck coolant into the combustion and produce white smoke? Also, I think that one cylinder will read more than 28psi different in compression than the others. On the bright side, these motors aren't very expensive. You could get one of the lower compression automatic motors, wait, I'm getting ahead of things a bit. Sorry.

If you are in a bind for cash (and I know you are) I can send you down my compression gauge. Since I STILL need to send that solenoid to you.


another thing, just check you pcv valve by blowing in it. I've bought one that didn't work out of the package before. (I've had another that just sorta sealed up, not by blowing at it, but sucking into it from behind). It still just sounds like boost in pressurizing the crankcase from it, otherwise it's the rings. But I really doubt even at 15psi with 77° intake temps and a 12:1 AFR you did damage.

Ya the new one actually does let air by when I blow on it on both sides. Hmmm....

ok then. that's not good. It's gotta seal up. That's what you get for $2 :td:

Just run without the PCV connected to the manifold to help diagnose the problem.

Are the stock headbolts know to lift under boost?

He was getting knock as evidenced by the oil pressure gauge bouncing around. Unfortunately I'm guessing rings.

I think you can blow through a stock Miata PVC valve and NOT the GTX valve because of the crankcase pressure from the turbo on the stock GTX. One of the few engine parts that didn't become interchangeable.

Frank

Would positive crankcase pressure from a failed pcv not cause the oil pressure gauge to be affected? Also, the valve that I just bought is the GTX one and it fits perfectly.

How is the gauge "going crazy", what is it doing?

Its not anymore, It did right when the smoke initially started coming out. The needle went back and forth violently. The engine was not shaking or making any strange noises at the time though. Thats why I'm asking if the positive pressure in the crankcase from a failed pcv could affect the pressure in the oil system. I think it would.

Ping can cause it to freak out (carbon pulses and what-not), so id assume other condtions might do the same. maybe search on it.

its it ok now?

no its not ok :( i fear the worst now, hg or piston crack. I might have to sell off some of this turbo stuff to accelerate my fe3 build.

I'll trade you manifold, dp, and turbos. ;) (doesn't help you much)


what happens when you run with no pcv line?

its too dark to find out today. I'll check tomorrow, I spent all afternoon doing some gay programming hw. Took all of like 4 hours, I guess thats what procrastinating gets me though.

ok, well I went to unhook the pcv and I accidentally broke the fucking plastic tube. So now I have to order that from somewhere. But anyways, when I start the car without the tube connected the car just revs out to 5k since there is no throttle plate blocking it. I think I'm just gonna sell off the turbo parts to build the 2.2L FE3 stroker and turbo that later in the year with a Borg Warner S256. That will be a monster 400+whp with boost still kicking in low. I'll make a decision in a couple of days.