NC with Cosworth making only 150 hp????

[elloco54]

Look again at your dyno sheet. that saw tooth graph is being caused by some sort of restriction. You have 3 choices 1 the bypass valve 2 the exhaust after your new header 3 something left in the blower. If you disconnect the exhaust at the header and tie it to the side. Make a quick (and loud) run if you still have no power you need to pull the blower and look for a problem there. Check the blower seals ,look for packing stuck in the runners, you should also be able to verify the operation of the bypass with a vacuum pump.

[fredmuggs]

Ok, here's another total shot in the dark. You're pretty sure its making 8 lbs boost and that's getting to the cylinders and out the exhaust without excessive restrictions. The other side of making more power is the extra fuel that's supposed to be injected into the cylinders and the spark to ignite the mixture. I'll avoid any speculation on missing sparks as you would probably notice uneven firing just by the sound of the exhaust, though it is a quick check to remove each plug wire individually to see if it makes a difference in the engine sound or exhaust, just to make sure all the coils are working well. Of course, a new set of Denso irridium plugs might not be a bad investment for the future as they tend to fire under more extreme air/fuel ratios than normal plugs.

So, maybe the duty cycle of the injectors on the car is getting maxed out and not flowing enough fuel to keep up with the extra air? Air/fuel ratio going very lean would be a clue to this condition. I'd check fuel pressure at the injector rail to make sure it doesn't drop off or flutter under acceleration, too. Easy to check and if it's solid it eliminates fuel pump and filter problems.

Since this is a used vehicle to you and it came with a cracked cat, I'd check to make sure you have the correct injectors on the car as well. Maybe the previous owner put some other injectors in and got the wrong ones back in the car after all the goodies were removed? Perhaps the ECU doesn't actuate these injectors as well? Also, Mazda sometimes has problems with the wiring at the injector or spark plug coil connectors as vibration tends to take a toll on the wires and they can be intermittent.

Like I said, total shot in the dark.

Hi, morrisg:

Excellent thoughts. The longer I chase the missing horse power, the more I learn about how the parts works together. And some really knowledgeable folks have been chipping in.

Fuel -- The injectors are new, came with the kit and supposedly higher flow than stock to support higher fuel requirements. I have not checked the fuel pressure under load. However, the Air Fuel Ratio (AFR) has been right on, responsive to the calibrators changes and remained exactly where he set it during load conditions.

Ignition -- One of the early changes I made when I realized power was way down was suggested by the calibrator who ran the second dyno and confirmed by Mike the calibrator at Moto-East. I installed a new set of NGK plugs, one heat range colder than stock and gapped at only .030" Colder was to accommodate higher chamber temps in a better fueled/aspirated motor. The relatively narrow gap was to accommodate the possibility that a denser air/fuel mixture in the force fed chambers might stifle the spark under load (The jargon is "blow out the spark."). I have not followed the directions in the '07 Shop Manual for testing the coil on plug (cop) NC ignition configuration.

Changing the plugs was the only change between dyno run 1 and dyno run 2. I believe I did pick up 8 HP between those runs. At least some of that was probably from the plugs. The COP ignition will fire a wet cigar. But the original plugs did look pretty sad when they came out of the motor.

Yesterday, I finally got someone to discuss the "static" within the dyno curves. I have to wonder if that is not a symptom of either the ECU throttling back for some reason or responding to some other problem that I have not yet recognized. I've emailed Moto Mike, the principal calibrator, to see if the logged throttle position data would actually show the throttle plate closing down while the pedal position is still wide open. Moto Mike says the "engine load" is off by around 15%. Maybe the ECU is cutting power 15%. I'd never know unless we find it in the data.

Thanks very much for your insights. I've wanted to learn more about logging and electronic engine calibration. I'm getting the crash course. Think I'll dig out the multimeter and check those coils. I can also try to fabricate aa fuel pressure gauge. Seems like there's a fuel pressure test port at the fuel rail. No excuse for not touching all the bases.
Fred

[fredmuggs]

Look again at your dyno sheet. that saw tooth graph is being caused by some sort of restriction. You have 3 choices 1 the bypass valve 2 the exhaust after your new header 3 something left in the blower. If you disconnect the exhaust at the header and tie it to the side. Make a quick (and loud) run if you still have no power you need to pull the blower and look for a problem there. Check the blower seals ,look for packing stuck in the runners, you should also be able to verify the operation of the bypass with a vacuum pump.

Hi, elloco54:

I, too, really believe what you call a "sawtooth" in the dyno curve is a solid symptom.

I'll be losing the rear cat and resonator for a few days next week. Not so much worried about the new muffler from Brian.

Magnasun says they believe the internals of the bypass to be in good shape. Makes sense, since boost comes in with increased throttle. I have verified the extrenal components are not blocked or damaged and the actuator works fine. But, the next time I go to the dyno, I will disconnect the bypass actuator during the runs to see if the "static" still appears in the HP and torque curves. May the bypass is somehow blowing open. Calibrator says engine air flow is down by something like 15 percent. Just don't yet know WHY it's down.

I checked very thoroughly for foreign objects in the blower and runners during the install. If I wind up pulling the blower, I'm adding a pressure port in one of the runners.

Thanks for your interest,
Fred.

[fredmuggs]

Buenos dias from the Eastern Time Zone:

Brian:
I've been counting all the "legitimate holes" in the intake and SC. There's the: throttle body, PCV, brake vacuum, evap line, boost sensor port, and EGR. Beyond those, boost (in fact all the air in the intake system) is supposed to go to the head.

Seems like I should be able to block the throttlebody and other lines and do a sort of leakdown test for leaks at the EGR and head. I could pressurize the entire intake system by pumping air into, say, the PCV port on the intake tube.

Wha-da-ya-think?

Thanks,
Fred

[morrisg]

How about another shot in the dark? The EGR is exposed to the boost? Ok, it's supposed to flow exhaust gas back into the intake, but what if it's leaking boost inlet air into the exhaust? Can you block it off or use a clamp to close off the hose to test this? You should be able to feel 15% more power so you might not need a dyno for this test.

[fredmuggs]

How about another shot in the dark? The EGR is exposed to the boost? Ok, it's supposed to flow exhaust gas back into the intake, but what if it's leaking boost inlet air into the exhaust? Can you block it off or use a clamp to close off the hose to test this? You should be able to feel 15% more power so you might not need a dyno for this test.

Hi, morris:

I hope that, when the engine is warm, the EGR valve will be closed and prevent my "leakdown test" pressure from bleeding off into the exhaust. The only part of the EGR I know of which is exposed on the 2L motor is a stainless tube which runs from the extreme rear of the block to the extreme rear of the blower case. There's no way to block it without removing the blower. And that's what I intend to save for the very last step.

Moto Mike the calibrator on this project said I shouldn't go back for another $75 dyno session until I started having traction problems. At this stage, traction problems from 200-plus Hp would be sweet.

Thanks for your input,
Fred

[elloco54]

If you pressurize the intake on a static motor what you will find is a big leak, as one set of intakes will be open. Sounds like you still have the stock pipe from the header to the muffler I would make sure that is not your problem especially if it a flow problem. I would also open the air filter air box and make sure nothing is blocked before the air filter

[fredmuggs]

If you pressurize the intake on a static motor what you will find is a big leak, as one set of intakes will be open. Sounds like you still have the stock pipe from the header to the muffler I would make sure that is not your problem especially if it a flow problem. I would also open the air filter air box and make sure nothing is blocked before the air filter

Hey:

You're right about the valves. I've been concentrating so much on the SC, I just dropped the internals out of the equation. Duh!

Intake path is clear -- first thing checked. Exhaust pipe comes off tomorrow. Not holding my breath, though.

Thanks for the response,
Fred

[fredmuggs]

Hi, Everyone:

I've been tinkering around in the background for a while with the help of Brian, my calibrator Moto Mike. Eventually even Magnuson, which built the blower kit, even got on board. Cosworth dropped off the scope because they really didn't know anything about the innards or functioning of the blower. They just marketed the thing. They ducked and dodged and blamed my calibrator for a couple of weeks without ever admitting they were out of their depth. When it all came down to my very specific questions about exactly how to inspect/test the bypass, they just quit answering my emails. Enough said.

Brian and Moto Mike up at MotoEast have continued, very patiently and without fail, to help me work through this. My premise has been that I did a really careful install and didn't want to tear it all down (and risk screwing up the REinstall) until I checked everything I could from the outside -- and it turns out, there was a lot to check. You folks have a lot of imagination. Now, all that has been done and I don't mind pulling down my work.

Brian has talked to Magnuson and they have agreed to bench test the blower for me. Didn't sound like they really liked the idea, but they may realize this could be a learning experience for them as well. They said the blower was designed to make only seven lbs and couldn't believe I was keeping my NC together at 8.5. Shows everyone can learn a little something if they keep their ears and eyes open.

Over the next week or two, I will pull the blower off and ship it to them for testing. I'm also planning to send in the idlers, since I've got a squeak at startup that sounds way too bad to ever get well. I have not been able to pin down the squeak to the idlers or the front end of the blower, even by using a stethoscope.

I will post again when there is any news. In the meantime, here's what I think is one of the most valuable lessons I have learned: DO NOT make a big change in a motor without spending the bucks to do a dyno pull BEFORE the change. If I had confirmed I had a sound motor BEFORE I installed the blower, it would have saved me a lot of time and trouble over the past couple of months running down stuff I could have/should have checked before the blower went on.

Thanks to all of you for all your time and interest,
Fred

[fredmuggs]

Just to keep everyone posted -- the blower's on the floor in the garage. It came off a lot easier than it went on: four hours instead of eighty. Starting tomorrow, I'll be waiting for an RMA from Magnuson so I can return it (at my expense, of course) for testing.

When I pulled the blower off, I found all the manifold bolts still tight. All hoses and connections were exactly as they should be. The metal manifold gasket was completely and uniformly flattened. I could see the outline of the gasket on the mating surfaces of both intake and head, completely around every port without a break. At the time of the install, the inside of the intake ports of the head were already stained by air/fuel mixture. Today, the inside of the intake runners of the blower were stained by the air fuel mixture from running since the install. But there was no staining on the mating surfaces of either the manifold or head indicating where the air fuel mixture leaked. Long and short of it -- It wasn't the install.

We'll see what Magnuson says in a few weeks.

Thanks for your interest,
Fred