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Old 10-05-2016, 11:10 AM   #601
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what are the CL initial duties table values like compared to your open loop numbers?

make your initial duties table numbers align closer to where your valve actually operates at. If youre telling the valve to hit 30% PWM but you need 40% to idle, that will never work...
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Old 10-05-2016, 11:13 AM   #602
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Quote:
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what are the CL initial duties table values like compared to your open loop numbers?

make your initial duties table numbers align closer to where your valve actually operates at. If youre telling the valve to hit 30% PWM but you need 40% to idle, that will never work...
I changed all his CL settings to match what was on my 94LE. As they are very similar setups, besides injector size. VVT motor, flat top, nb idle valve.
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Old 10-05-2016, 11:38 AM   #603
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based on your OL table, try these values in the initial duties table (actually add like 2% to this entire thing):



Lars needs much less PWM% than you. I'd also revert back to your original idle cranking table, but keep all the rest of his CL stuffs.



Last edited by Braineack; 10-05-2016 at 01:55 PM.
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Old 10-05-2016, 12:05 PM   #604
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Check this **** bitches...fun stuff. The inside of a modern 250cc motorcycle engine. Five titanium valves, two cams, one cylinder, 37hp.



I miss my YZ 450
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Old 10-05-2016, 01:08 PM   #605
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Cams and valves are for pussies.
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Old 10-05-2016, 05:09 PM   #606
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Quote:
Originally Posted by shuiend View Post
I changed all his CL settings to match what was on my 94LE. As they are very similar setups, besides injector size. VVT motor, flat top, nb idle valve.
Quote:
Originally Posted by Braineack View Post
based on your OL table, try these values in the initial duties table (actually add like 2% to this entire thing):



Lars needs much less PWM% than you. I'd also revert back to your original idle cranking table, but keep all the rest of his CL stuffs.
Thanks guys. Trying these settings and suggestions before the weekend.

Only two races left in the season, on the dirtbike. I have a minor points lead for the championship. The bike is in many pieces right now, and I have a race on sunday.
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Old 10-17-2016, 09:22 PM   #607
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Since day one with this engine, I have had coolant puke from the overflow whengine I park the car. Various amounts, but usually a small puddle. Burped the system 100 times. No overheating. 949 radiator and cap. ARP hardware. 60 lbs.

Should I accept that it's a head gasket problem?
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Old 10-17-2016, 09:25 PM   #608
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You can chemically test the coolant to see if it's a head gasket, there are test strips you can buy that will show if exhaust gasses are contaminating the coolant to find out if it's a head gasket. Also very likely for one of the plugs to look different if coolant is getting in that cylinder.
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Old 10-17-2016, 09:27 PM   #609
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All plugs look identical. I'll check for the strips.
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Old 11-09-2016, 08:58 AM   #610
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Miata Masters, I have a riddle.

After I went and drove my car pretty hard, it started running on 3 cylinders. I had just modified the tune and at 20 psi it ran at AFR 12.3-5 for a second, five or six times in ten minutes. I was not super concerned since the lean condition was lasting less than 1.5 second. My AFR safety was set at 1.5 seconds and I never hit that. So I came home, changed the plugs even though the ones I was running looked fine. No real change. Cold, the engine ran fine, once it warmed up it would run on 3 cylinders until i shut it off and let it cool. Anyway, I assumed the worst and started tearing the thing apart expecting to see the worst. Fast forward a couple days.

It turns out that I can remove the entire engine and trans, about as fast as I can remove just the head/turbo assembly.

The intake tract was full of oil. Now I really think that something is broken. Not sure how the oil got past my catch can. No idea on that, but it did.

The engine: It looks great! NO sign of det at all. everything looks brand new. no signs of leaking head gasket, no burnt valves, no erosion on the piston edges. I DID find a questionable connection at one of my fuel injectors. the plug was super loose. Could an injector if unplugged, aloow all of that oil to somehow end up in the intake? As I type this, I don't even know how that is possible.

I still don't trust the valve train. A bent valve the only thing I can think of that may cause it to run differently when hot/cold. What do you guys think about this.
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Old 11-09-2016, 09:53 AM   #611
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No, injector will not do that.

Oil in the intercooler? You didn't do a comp test first did you? Are we pressurizing the crank case and overwhelming the PVC? that seems to be a common thing around here lately.
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Old 11-09-2016, 10:32 AM   #612
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Unfortunately I did not do a compression test. I figured the engine was broken and that was that. I never expected to not find anything when I opened it up. Now I have to wonder all sorts of things, or pull the bottom end apart, or put it together with fingers crossed.

I would expect that if I had pressurized the crank case, I would find a pool of it in my seperator. In fact I was thinking the opposite . That maybe I was making SO much vacuum from the venturi on the turbo inlet, that I was just o er powering the seperator .
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Old 11-09-2016, 10:18 PM   #613
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Injector could cause it to drop a cylinder, but not oil. If blowby is excessive, probably the rings are bad. If not, your catchan setup is probably bad, or your PCV valve is pressurizing the crankcase (it's bad). I just deleted the PCV and run a hose from the drivers side off the side of the car, no problems and it's simple. I don't have much blowby at all though, stock valve cover.

For the head, you can pull the cams out, and then pour mineral spirits down the ports to check for a bad valve. Should stay dry, maybe barely wet after a few minutes. If it's immediately wet it leaks, if it pours out it needs repair.
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Old 11-10-2016, 09:53 AM   #614
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I pulled the intake apart two weeks ago for unrelated issues, and it was absolutely clean. no oil. I don't run a pcv valve. I have a venturi in the intake pre turbo, it pulls through both of the factory vents on the valve cover. both of those have been opened up to .500, chor boy, and modified internals to pull air from the top of the VC instead of pooling oil on the floor area.

Can this happen : If an injector is disconnected and not adding fuel to a cylinder, could I in theory be pulling enough vacuum to draw up oil through a non firing cylinder ? I need to measure the amount of vacuum I make, but I think it's an absurd amount . I was hoping this pic showed my vacuum routing, but it doesn't.
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Old 11-10-2016, 09:54 AM   #615
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Wait, yes it does.
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Old 11-10-2016, 10:24 AM   #616
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No. A disconnected injector won't do much more than cause that cyl not to fire. No harm otherwise
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Old 11-10-2016, 10:32 AM   #617
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More details . ... All of the pistons and combustion chambers are DRY. no oil. I am leaning towards a failure of some sort in the head.
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Old 11-11-2016, 04:12 AM   #618
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You're sucking all the oil in with the venturi, get rid of it and it's fixed.
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Old 11-11-2016, 10:17 AM   #619
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I agree with Pat, I know you have the venturi to try and clear the block in boost but without a source of fresh air you're pretty much just capping the block off and giving blowby one tiny exit. With one tiny exit, you get insane air velocity. With insane air velocity, the oil has no chance of falling out of suspension in the air without a swirl pot. Chor boy does not work, never has IMO. All it does is reduce camber volume, increases the air resistance and therefore the velocity of the air running through the loop. Whatever does manage to condense onto the chor is just going to be sucked right back off, anyway. The oil needs to collect into a large enough pile to flow back, but not small enough droplets that the air can pick it back up and sling it forward again.

If I were you, I'd try a conventional PCV setup with a single catch can between the intake manifold. Delete all the wadding. I bet it'd be a thousand times better.
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Old 11-11-2016, 10:36 AM   #620
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Possibly . Except that I never had any oil in the intake, until it started running on 3 cylinders . Two weeks ago it was sparkling clean after 3k miles. After losing a cylinder is when I got oil. but still no oil in the combustion chambers . plugs are dry too.

I'm going to take the head apart to install some new valve springs, never did that when I built the rest of this thing. At that time I can check to make sure everything is free and not binding up. I just don't have any obvious reason why I am losing one cylinder once it warmed up.
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