Part Throttle surge at 0 PSI?
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Originally Posted by DAVE396LT1
What's part throttle? 50%? 99%? You really have to define your terms, because if you mean you only see boost at exactly WOT, something's wrong on -your- car!
I see boost as the rpms come up at part throttle. That's to be expected: the blower achieves greater than 100% VE even with the "restriction" of half-throttle, and it does it easily on my car... and my bypass works fine, as you can clearly hear when you vent it to the atmosphere.
I see boost as the rpms come up at part throttle. That's to be expected: the blower achieves greater than 100% VE even with the "restriction" of half-throttle, and it does it easily on my car... and my bypass works fine, as you can clearly hear when you vent it to the atmosphere.
I'm talking 30-50%. Anything more than that, yes you see boost, but the problem does not present itself under boost.
Just for fun I removed the hose from the bypass valve to the inlet side of the blower. Same problem, and the bypass valve is working. Makes a nice PSSST sound on shifts...
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From: Redmond WA
Originally Posted by ztrips
Just for fun I removed the hose from the bypass valve to the inlet side of the blower. Same problem, and the bypass valve is working. Makes a nice PSSST sound on shifts...
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Originally Posted by Bruce
well, 14psi of boost at 4600rpm and my junk ATI bypass valve is relieving air to the atmosphere. But soon I will be replace it with Tial 50mm bov.
Bruce
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Originally Posted by DAVE396LT1
Does you car have a MAF? Doing this will make it run super-rich and probably die, since its still calcing fuel based on the total air the MAF sees, which includes the stuff you blow out the bypass.
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From: Honolulu, HI
Originally Posted by DAVE396LT1
What's part throttle? 50%? 99%? You really have to define your terms, because if you mean you only see boost at exactly WOT, something's wrong on -your- car!
I see boost as the rpms come up at part throttle. That's to be expected: the blower achieves greater than 100% VE even with the "restriction" of half-throttle, and it does it easily on my car... and my bypass works fine, as you can clearly hear when you vent it to the atmosphere.
I see boost as the rpms come up at part throttle. That's to be expected: the blower achieves greater than 100% VE even with the "restriction" of half-throttle, and it does it easily on my car... and my bypass works fine, as you can clearly hear when you vent it to the atmosphere.
More air demand by cylinders creates low pressure (vacuum) = open bypass = NO boost.
This in turn is regulated BY the throttle.
Unless you're running a radical cam, I don't see how many engines can see boost at mid throttle. But it ALL DEPENDS on your application. Basically, we're talking about stock mills with street blowers.
Nothing is wrong with my car in relation to bypass valve operation and boost production.
If you can quench your manifold with 14.7psi of atmospheric pressure at 50% throttle, then you're at your threshold for the bypass valve closing and making boost. It's that simple, THAT is what "part" throttle means to me. Ok?
How did this turn into a mountain out of a mole hill? Sheesh. We're supposed to be helping each other, not getting into petty arguements.
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Ztrips, if your bypass is working appropriately, then I will tell you to just get a tune. Get your A/F ratios checked on a dyno, it's the only way to be sure.
This is something you might want. I'm getting mine welded in this weekend:
www.zeitronix.com
If you need a good chip tuner, www.azzatochips.com His name is Jesse and he's on THIS very forum. aka ski_dwn_it. He did mine and it ran great (having problems now, but I don't want to say it was his fault) The good thing is, he charges $250 flat rate for UNLIMITED burns. (at least, that used to be his policy) send him a message.
This is something you might want. I'm getting mine welded in this weekend:
www.zeitronix.com
If you need a good chip tuner, www.azzatochips.com His name is Jesse and he's on THIS very forum. aka ski_dwn_it. He did mine and it ran great (having problems now, but I don't want to say it was his fault) The good thing is, he charges $250 flat rate for UNLIMITED burns. (at least, that used to be his policy) send him a message.
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From: Redmond WA
Originally Posted by ztrips
No MAF. But even if I did, it wouldn't matter where the bypass was dumping as long if the bypass was before the MAF.
And vvv90, take a pill. It's ok to be wrong once in a while, don't take it or make it personal.
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From: Honolulu, HI
Originally Posted by DAVE396LT1
And vvv90, take a pill. It's ok to be wrong once in a while, don't take it or make it personal.
You're right Ztrips.
Last edited by vvv90; Sep 15, 2004 at 02:17 PM.
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Originally Posted by vvv90
You would like to believe I was wrong. Obviously you don't read very well, or comprehend anything. What's it like having the IQ of an ape?
I'm going to hook up my laptop tonight and do some runs to see what is going on.. I'll post my findings. Right now I'm leaning towards this being a fuel pressue /FMU issue.
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Do the laptop thing, it's hard to tell. Though I wouldn't rule out your opti, afterall at -psi to 0 or even +1 psi your car should be operating as if it were stock. Unless you've had your computer reprog'd or the fmu is doing something funky.
What fuel pressure are you seeing at 0 or +1?
What fuel pressure are you seeing at 0 or +1?
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Originally Posted by vvv90
Do the laptop thing, it's hard to tell. Though I wouldn't rule out your opti, afterall at -psi to 0 or even +1 psi your car should be operating as if it were stock. Unless you've had your computer reprog'd or the fmu is doing something funky.
What fuel pressure are you seeing at 0 or +1?
What fuel pressure are you seeing at 0 or +1?
I was poking around last night, looking at all of my vacuum lines. I've got manifold vacuum/pressure feeding the FMU, bypass valve, boost guage, and MAP for boost retard. There is also a line going off with a check valve and something else (filter maybe?) going down to my optispark. Seeing how my car is a 92, I guess someone has changed out the opti for a vented unit?? I feel kinda dumb not knowing that, but the work was already done when I bought the car..... There is also another vacuum line that looks like it is coming from the opti, going to a spot on the intake tube just after the air filter....
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From: Honolulu, HI
Originally Posted by ztrips
Not sure on the fuel pressure. Chip is stock (for now.. getting it zapped soon).
I was poking around last night, looking at all of my vacuum lines. I've got manifold vacuum/pressure feeding the FMU, bypass valve, boost guage, and MAP for boost retard. There is also a line going off with a check valve and something else (filter maybe?) going down to my optispark. Seeing how my car is a 92, I guess someone has changed out the opti for a vented unit?? I feel kinda dumb not knowing that, but the work was already done when I bought the car..... There is also another vacuum line that looks like it is coming from the opti, going to a spot on the intake tube just after the air filter....
Did you buy your car with the blower already on it? Because the inlet vacuum hose for the Opti normally goes in the intake bellows instead of pre-blower or near the air filter........That hose is PRE-blower right?I still have no idea why your car would be doing what it's doing without any boost. It's tough to say without checking the Fuel pressure and AF ratios on a dyno or some good scanning software. Maybe having your chips burned will solve that problem....Might start others too.
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Originally Posted by vvv90
You should definitely get a FP gauge. Just my $.02
Well then, it sounds like your Opti is newer than 12 years old, and vented! Did you buy your car with the blower already on it? Because the inlet vacuum hose for the Opti normally goes in the intake bellows instead of pre-blower or near the air filter........That hose is PRE-blower right?
I still have no idea why your car would be doing what it's doing without any boost. It's tough to say without checking the Fuel pressure and AF ratios on a dyno or some good scanning software. Maybe having your chips burned will solve that problem....Might start others too.
Well then, it sounds like your Opti is newer than 12 years old, and vented!
Did you buy your car with the blower already on it? Because the inlet vacuum hose for the Opti normally goes in the intake bellows instead of pre-blower or near the air filter........That hose is PRE-blower right?I still have no idea why your car would be doing what it's doing without any boost. It's tough to say without checking the Fuel pressure and AF ratios on a dyno or some good scanning software. Maybe having your chips burned will solve that problem....Might start others too.
FP gauge is going in for sure. just need to get another pod for it...
Blower was on when I got the car. There are two hoses to the opti. Well, one for sure the other one I can't get a look at where it goes it, but it heads that direction (there isn't a lot it could go to down there...). One is PRE-blower, the other is manifold pressure, but with a check valve so it only sees vacuum. I need to climb under the car again tonight to find out for sure.
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Originally Posted by ztrips
FP gauge is going in for sure. just need to get another pod for it...
One is PRE-blower, the other is manifold pressure, but with a check valve so it only sees vacuum.
One is PRE-blower, the other is manifold pressure, but with a check valve so it only sees vacuum.
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Originally Posted by vvv90
Yep, that's how it is supposed to be hooked up. Only at cruise and idle will air be pulled through the Opti.
I figured that was the reason, but I'm not sure why I've got two lines headed down there.... I need to dig into it tonight.
Oh, and I got my Carroll Superchargers catalog today
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From: Honolulu, HI
Originally Posted by ztrips
I figured that was the reason, but I'm not sure why I've got two lines headed down there.... I need to dig into it tonight.
Oh, and I got my Carroll Superchargers catalog today
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Originally Posted by vvv90
Yep, one line feeds fresh air from the air filter pre-blower side into the aluminum base of the Opti, the other line sucks the air out of the Opti cap into the manifold.
I thought they're called Blowerworks now or something. Is that what kit you have? Carroll? What components do you have completely? Superfueler? What kind of FMU? Water injection?
I thought they're called Blowerworks now or something. Is that what kit you have? Carroll? What components do you have completely? Superfueler? What kind of FMU? Water injection?
That makes sense now... The blower kit went on 2 years ago, so if they replaced the opti at that point (and hopefully the water pump...) I should be good for a while longer.
I have a regular vortech kit. Carroll is called blowerworks now (blowerworks.net , not.com). I have the Vortech FMU, Ford injectors, Crane-HI6, etc.. I'm going to get a Carroll water injection kit and maybe a superfueler. Greg Carroll also mentioned a modification to the Vortech blower intake that could yield some additional HP.
What in car fuel pressure gauge is recommended? I'd want one with an isolator...
BTW- They are having a killer sale on the basic water kits right now....
Last edited by ztrips; Sep 15, 2004 at 04:37 PM.
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OK, did a datamaster run. I'm not scan/tune expert so I'm not sure exactly what I'm looking at but here it goes...
first run:
TPS% was right at 30%
1850 to 5700 RPM, second gear.
My STerm counts went from 128/128 to 117/140. Left side started at 128 went to 132 then dropped to 117. Right side started at 128 and just kept climbing all the way to 140.
LTerm counts were 127/122 and ended up 125/121.
Spark advance started at 22 and went all the way to 40. My knock count went from 168 to 393 with the spark retard jumping all over the place from 0 to 1.2.
second run:
1800 to 2600 RPM, 4th gear
STerm counts stuck at 128/128
LTerm counts started 128/122 then fell to 120/119
TPS 35%
knock count 825 to 1800
spark retard mostly between 1.0 and 1.8 degrees
spark advance from 21 down to 8 degrees
So I'm not sure what this means... A lot of knock that's for sure.. I don't like the timing bouncing all over the place. That mount account for the surging... Any ideas?
first run:
TPS% was right at 30%
1850 to 5700 RPM, second gear.
My STerm counts went from 128/128 to 117/140. Left side started at 128 went to 132 then dropped to 117. Right side started at 128 and just kept climbing all the way to 140.
LTerm counts were 127/122 and ended up 125/121.
Spark advance started at 22 and went all the way to 40. My knock count went from 168 to 393 with the spark retard jumping all over the place from 0 to 1.2.
second run:
1800 to 2600 RPM, 4th gear
STerm counts stuck at 128/128
LTerm counts started 128/122 then fell to 120/119
TPS 35%
knock count 825 to 1800
spark retard mostly between 1.0 and 1.8 degrees
spark advance from 21 down to 8 degrees
So I'm not sure what this means... A lot of knock that's for sure.. I don't like the timing bouncing all over the place. That mount account for the surging... Any ideas?