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Old 10-26-2008, 11:49 AM   #1
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Default Questions for guys running 12-15 psi.

I'm at 10psi and the car runs and performs Toney the tiger GRRrrrreat!

I always want more power. And was thinking of turning the boost up. I know that 12psi should be the peak for dependability.

But when you cross that line. How long does it last. Does it really give the motor a beating. I have a good running 1.6L, some lifter tick when it starts up. But it goes away like everyother 1.6L.

Will the motor just give up the ghost, or the rings wear out fast.
I know you can't predict everything that will happen. And I know differant motors will have differant parts fail.

But on average, with practically no track racing, lots of heavy foot street driving, shifting at 6500 instead of 7200, And then the occasional all out street race. How Long do you predict it to last.

This is a daily driver.

---------------------------------
I may leave it a 10psi for dependability, and set 14-15 psi on the ebc with a toggle switch.

You oppinions are welcome.
Even UrbanShoots But sex. Since we are there. Dr 90210 finnally explained how women get a ***** in a sex change!
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Old 10-26-2008, 12:25 PM   #2
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I boosted my daily driver 94 because I was sick of it feeling so slow compared to my already turbo'd 94. I threw a BEGi S kit on it at 250k miles in May of '08. The motor is original. I'm horrible with maintenance on it because I drive so much and 3000 miles goes by so quick. Usually I get it by 4000 but sometimes I go 5. The car now has 267k miles and I have my boost controller set to bring me to 15lbs as early as possible and hold it to redline. On cold days it makes a lot more boost a lot sooner and I've been bouncing off the boost cut of 225kpa. Yesterday I changed that to 240 cuz I hate when it does that. So yeah, I'm throwing 15 lbs at this motor with spikes up to 18 and it's still going and I beat on the thing. I do use some oil but it used oil before the turbo went on too. I think as long as you keep your intake temps under control and avoid knock and run safe AFRs they can be pretty reliable over 12psi.

And the toggle switch is a great idea. With switch off I make 11-12 in warmer weather, switch on is 15. With temps in the 40s last week it was making 15 with the switch off. For switch on I cut my DC values all down to keep it at 15, it just makes it a lot sooner. Until someone gets this closed loop boost control working I have 3 different Boost DC Target tables for different ambient temps.
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Old 10-26-2008, 10:15 PM   #3
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Quote:
Originally Posted by paul View Post
Until someone gets this closed loop boost control working I have 3 different Boost DC Target tables for different ambient temps.
I wish someone would, I tried but failed... and hitting boost cut whenever its under 60 degrees sucks


oh and for the OP, 14 to 15 psi for like 10k miles now, and its doing fine. Just have a good tune and your set.
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Old 10-26-2008, 10:18 PM   #4
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this is why i like my solenoid switch. in the least I can fail to wastegate when it's too cold and I overboost when it's colder and i havent changed my map.
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Old 10-26-2008, 10:23 PM   #5
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And that's why I'll be running MBC until someone figures it out or I'll buy a different EBC controller all together.

To the OP I'd say you're not really crossing any defined lines. Reliability is a function of many variables. If you knock stuff will break fast. If you do everything you can to keep that from happening and keep the engine well tuned, it should hold up fine. Drivetrain reliability will go down with added power, but you can make up for it with mechanical empathy. Some like the idea of low/high boost. I personally would rather have high all the time.
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Old 10-26-2008, 10:24 PM   #6
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Quote:
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this is why i like my solenoid switch. in the least I can fail to wastegate when it's too cold and I overboost when it's colder and i havent changed my map.
I just wish that wasn't the only way to do it. I am tuning my EBC a little bit at a time, and this time of year there is a 30 degree difference over the course of a day, and more than that in a week. This temperature difference makes for difficult tuning.
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Old 10-26-2008, 10:24 PM   #7
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+1 for drivetrain going first.
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Old 10-26-2008, 10:57 PM   #8
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Quote:
Originally Posted by Braineack View Post
this is why i like my solenoid switch. in the least I can fail to wastegate when it's too cold and I overboost when it's colder and i havent changed my map.
yeah but wastegate = slow boost onset and lower boost overall. I dont want the car to be slower in the cold (would prolly help traction tho haha). I want my cake and to eat it too.
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Old 10-26-2008, 11:10 PM   #9
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It's not that bad on wastegate - 206rwhp

Name:  wastegate_vs_solenoid.jpg
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the main thing is I can prevent overboost till the next time I have the laptop to low my DC%.
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Old 10-27-2008, 12:17 AM   #10
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If it's that much trouble, I'll just use the manual boost controller.

I'll turn the *** a little. LOL

I'm not becoming speedracer, just Racer X. LOL
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Old 10-27-2008, 12:58 AM   #11
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I maintain my cars very well, and I show empathy durring daily driving. But I don't show empathy while racing. lol.
So I guess it will work. I drive my car about 30,000 miles a year.

And the weather in Texas changes continually all day. Manual controller it is.

Last edited by Toddcod; 10-27-2008 at 01:23 AM.
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Old 10-27-2008, 01:59 AM   #12
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Quote:
Originally Posted by Toddcod View Post
If it's that much trouble, I'll just use the manual boost controller.

I'll turn the *** a little. LOL

I'm not becoming speedracer, just Racer X. LOL
Honest to God... I called FM early last week and asked them how I could fix this cold weather overboost problem, and they told me to get a manual boost controller... So a $40 part is better than the EBC on the Hydra. Man I wish I would have known that when I bought this kit

Back on topic, turn the boost up. 12 is more of a soft limit on a 99. Many NAs here run up to 15 with few issues. Of course I assume no liability if you blow your stuff up
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Old 10-27-2008, 10:40 AM   #13
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Quote:
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If it's that much trouble, I'll just use the manual boost controller.

you could use the solenoid in conjunction with the mbc
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Old 10-27-2008, 10:49 AM   #14
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You have an overboost problem in cold weather with the Hydra? I thought they had a closed loop system that worked well. a KPA target map. Y8s?
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Old 10-27-2008, 10:52 AM   #15
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You'll still have the same cold weather problems with an mbc. The car will make more boost when it's colder. Even without any boost controller you can have the problem. If i wanted no more than 12psi on my car I would be over shooting that with just the wastegate pressure when it gets cold. In 40F ambient wastegate pressure is 15psi for me. Tell me how to fix that with an MBC.
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Old 10-27-2008, 11:01 AM   #16
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Just an idea here, would taping a piece of, say....cardboard over 50-60% of the FMIC have any effect? it would reduce the cooling abilities of the I/C in cool weather and with some tuning on how much is covered could get you back to the same cooling abilities in cool weather as you have in warmer weather.
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Old 10-27-2008, 11:09 AM   #17
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Not cooling the air AFTER the turbo isn't gonna help. The warmer air would be of even higher pressure. Now maybe if we warmed the air before the turbo....

a la DEI
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Old 10-27-2008, 11:11 AM   #18
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Quote:
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The warmer air would be of even higher pressure. Now maybe if we warmed the air before the turbo....

a la DEI
HEH? I thought colder air being more dense was a pretty universal statement? Thus making the air less cool (warmer) would DEcrease the pressure?
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Old 10-27-2008, 11:18 AM   #19
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more dense as in more oxygen per unit of volume. well more everything per unit of volume.

what happens to your tire pressure when you drive the car? as the tires heat up it heats up the air and the pressure goes up.
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Old 10-27-2008, 11:19 AM   #20
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Quote:
Originally Posted by paul View Post
more dense as in more oxygen per unit of volume. well more everything per unit of volume.

what happens to your tire pressure when you drive the car? as the tires heat up it heats up the air and the pressure goes up.
Didn't think about it that way, oh well, it was a thought.
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