yeah that's my suspicion.

early on in the build I experienced a boost spike and a crushing can noise, running up a steep hill under boost. I reckon things went a miss at that point.

I know the rear rotor has strange uneven compression and the car doesn't breath anywhere near what it should.

I reckon I'm lucky that the engine is still running and making ok power.

 

Beat the hell out of it and see if you can break it . Then rebuild it and use the knowledge you gained to know what the limits are next time

 

lol yeah I like your thinking

trouble is with the engine in the state it is I'm not getting a true base line for what works. initially @ 8psi I was hitting around 290 g/s with a bad setup. now it struggles to make that boost on the same gearing and @ 10psi while it flows more down low I'm not sure it will hit those figures. while I'm not pushing it till the bov is fitted - I'm only hitting 150% loads. if I got back to a new fresh motor I reckon it would get another 20%.

so with the dud motor I really can't push it. if I push this motor to the limit and then drop it back a notch it would probably still be a motor breaker. my current gearing of around 12psi would probably be 15psi on a strong motor.

I'll keep going. Iron out the fuelling bugs. then rebuild and go back to the original gearing and slowly step back up.

 

I thought I was just going to move the throttle back to it's normal location bolt on the BOV and be off driving...

not going to happen. changed it all over and fitted the valve in the dark last night and the car wont start. it just dies. with some throttle it will hold a lumpy ide at 2000rpm. sounds like it is going rich and lean or starving of air.

time to sort out what's wrong

 

well a quick test has narrowed it down to the location of where the air is recirculated back to the intake. there isn't a lot of scope where it goes due to limited space. you can see where it joins the intake below.



in comparison to my old intake I have straightened the flow. the maf is silghtly more lumpy than my old one due to the weld in front of the MAF (and a slight step in tube sizes). below you can see a log comparison to the MAF hunting with the SC plumbed in (with BOV) and the relativity smooth flow of the same MAF intake used NA.



the other possibility is that the BOV cant flow enough air or it is closing as the engine revs. it's amazing how much air the SC flows at idle. no wonder when pushed through a 1.25" tube at 90 deg top the flow it makes the MAF go crazy.

I reckon this would be the main limitation of getting a MAF setup to work with the esmeril turbo kit. it's not the short MAF tube - it would be the recirculation that will be the problem.

 

The fact that you are dumping compressed air in directly at the "vacuum source" so close behind the MAF is most likely the cause for the poor signal. WHen the "puff" of air is released into the line, the air stalls over the sensor, and subsuquent hilarity ensues. THis will also be something when the entire intake is compressed at WOT< and you let off the gas: BOV opens, and the pressure comes back into the tube, stalling the air flowing over the maf.

To get a cleaner signal, you may have to make the MAF quite a bit further away from the Bypass intake, or put the maf on the OTHER SIDE of the bov... close to the intake manifold. That one would probably give you the cleanest signal.

I'm still a big fan of throttling the supercharger, the way you started the project...

was the drive just not "good"?

 

it's not so mush a puff and a huge rush of air!

the MAF works by itself and the car will idle with the BOV and recirculation - if I disconnect the MAF sensor. so it is purely a sensor issue with the new turbulence.

considering my MAF is only about 6" long before the sensor there isn't much room to move. but I'll try a few thing's to see if I can get the re-circulation to work.

it's not that having the throttle before the SC was that bad. it works really well it is the air volume in the front-mount intercooler that is the main issue. I had worked the volume down to a point the system worked well and has great throttle response in first and second gear. I just feel there is a "little more" hiding in it.

the bypass (BOV) is an attempt to find that. better or worse at least I will know.

 

it seems the tune may have been playing up. it seems to run ok. the A/F seem better while in boost but there are still maf issues and it runs pig rich at low rpm cruise.

I took it for a good drive (logger failed ) and while it is different it is not really better or worse than the previous setup.

it makes cool bov sounds and has cured some compressor/TB noise issues but that's about it.

 

only way to fix it is to move MAF to "blow through".

right before the TB< but well after the BOV.

 

after playing round with it for the day...

I found oil in the bypass tube when I was playing with the routing.
no wonder it was throwing P0172 "system to rich" there was oil all over the maf.
oil down the compressor and pipe work.

farks me where it is coming from.

worst case it is the compressor and supercharger leaking oil.

it might just be from the BOV dam synapse engineering quality isn't the best. I found a miss drilled hole. the fittings were all loose and the thing has been oozing grease from every orifice.

the oil seems to black to me coming from the BOV.

 

well I don't think the oil is the SC. it only has about 1L in volume and it hasn't dropped since last check. it is also clean and clear and a thinner viscosity.

it seems to be engine oil but I haven't got a clue where it came from. the usual path from the filler neck is clean. the oil metering pump line is contaminated but it might have been sucking it up and not blowing it out?

when in doubt return to NA I say lol

 

when in doubt figure it out , has a better ring to it .

where are all your vac hoses that came off the stock intake routed ?

 

???
Wow - that's a lot of bad tuning.
If your setup will allow you to pull the MAF and run "fine", then you are exceptionally insensitive to a poorly running car.
The "limp" mode for no MAF is a 1700 RPM idle at 12:1.

 

that's with mazda's tune

The std tune has enough leeway for the car to run in case there is a failure. also starting doesn't seem to have much to do with the MAF's reading at start.

the throttle can also be disconnected and the car will still start. It will hold a high idle but will start happily. I also found it will rev and respond to throttle input slightly .

mazda must be **** at tuning lol

 

Your plenum is leaking air and holding the idle up.
How can it respond to throttle input if you disconnect the throttle? lol

The point is that Mazda's tuning is designed to default to 1700 RPM and a very rich AFR if the MAF goes away. It sticks the car in open-loop, so it should be (barely) drivable.

My comment was that you state that it runs OK in this state and I don't think many people would feel that state of tune is OK.

 

the vac hoses are what got me playing with the system. I was trying to rid the setup of one of the non return valves on the jet air lines. the greddy system ended up placing this just before the throttle and leaving it unchecked as it would see vac and boost.

I tried that system out but due to the air pump of the sc I thought I was getting silly flow down the jet air lines. so I returned to a check valve on both the jet air and OMP lines after the maf and before the compressor.

I just started using a catch can on the oil line. but have to admit it wasn't on for the BOV test run where it was plumbed in after the maf and before the compressor. when I noticed the oil it was vented to atmosphere. The contamination could have occurred earlier but the line was clear.

 

the plenum may be leaking air but I don't think so. I was confused about the throttle response but it was there. I was testing a seconded TB I have and it was on the dash so I could see it working. the engine was on and idling with the STD tb in place. when I pushed the accelerator to open the second tB I noticed the engine was responding I put it down to a mixture change acceleration pump feature.

sate of tune ok? running ok? It was idling happily and not coughing or spluttering. I wouldn't drive it like that but it was ok in my book

 

I hit 316g/s my first MAF readings over 300g/s so I'm really happy. after

hitting 295 early on in the build it has been all low flow from there on.

300g/s might not be much but it's a milestone for me.

 

cool man - that might get you close to 300whp - maybe .

 

maybe maybe not

it's not really that I have gained flow - I just made all the flow usable.
I'll go back to the bigger inter-cooler and see if I gain get a bit more.

 

Still having oil problems?

I was away from the thread for a bit...

Gotta make sure any crankcase ventilation and vacuum lines are all plumbed after the MAF by a decent amount... and that also goes for what the BOV dumps off, as it will have that oil IN it...

I probably am a bit behind on that tho so <shrug>

 

I haven't had any problems since the first drive. it was most likely engine oil. from where I'm not sure.

I have a oil catch can now so hopefully that will stop it occurring again.

I have never had a problem with the OMP lines and jet air lines being connected close to the MAF they suck and have check valves that stop them from blowing.

the crank case vent may be an issue. I use to have it vented to behind the air filter before the MAF and it wasn't a problem. the engine didn't suck hard on it.

now it is just before the compressor. Although I doubt it flows enough air to stuff the MAF reading.

 

one of the issues with your MAF reading is the reduction in tube diameter right after the MAF. Reducers that close cause turbulence.

If you could move that reduction to AFTER the 45 that would be much better.

The oil is more than likely (from your description) from filling/topping off your oil. your catch can should resolve that.

 

the reduction in diameter has little effect. I have been doing that for ages and the MAF doesn't care the only issue is air flow disturbance due to the rush of the air that is being recirculated.

 

I would buy a different air filter that you can fit up front outside the engine bay. That gives you more space to get stable airflow before and after your MAf .