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Old 09-30-2007, 08:59 PM   #1
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Default Lowering Boost Method

So I've been searching around to see if I can find a way to lower the boost in my T3. I know that lengthening the actuator rod will work but will make it spool slower.

Here is another method I found:

http://www.denverspeed.com/wastegates.html

It looks interesting but the author doesn't give much details. Does this method help reduce the negative effects of lengthening actuator rods? What the benefit of adding this spring?

Thanks guys.
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Old 09-30-2007, 09:01 PM   #2
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why would you want less than 7psi?
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Old 09-30-2007, 09:11 PM   #3
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I am a newbie at this so I want to set it at 5 psi and work my way up. I am purschasing a WB and will be using that to tune. I just want to set the turbo at a "safer" setting, learn to tune it, then increase the boost later on.
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Old 09-30-2007, 09:21 PM   #4
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Quote:
Originally Posted by jay526 View Post
I am a newbie at this so I want to set it at 5 psi and work my way up. I am purschasing a WB and will be using that to tune. I just want to set the turbo at a "safer" setting, learn to tune it, then increase the boost later on.
Agreed, I'd prefer to start a bit lower than the 8psi on my can. I've never tuned a boosted car from scratch so there is about a 90% chance I'm going to toast my motor.
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Old 09-30-2007, 10:07 PM   #5
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Depending on what EMS you're using, the megasquirt base maps we have available are pretty damn close for just about any car. Close enough that you could retard the ignition a degree or two extra and bump the fuel a little rich and head down the road with autotune on safely at 7 psi. Atleast that's what I did.
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Old 09-30-2007, 10:10 PM   #6
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just use a reverse helper spring problem solved. With that i was able to run 5 psi on a 12 psi can.
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Old 09-30-2007, 10:18 PM   #7
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CHICKENS! all chickens!

how about not flooring it until it's tuned. you shouldn't really drive it until it is anyway. but not flooring it will keep you from full boost.

but leaving the WG open is fine. more importantly: what do you care if you build boost fast or not if the car's not tuned properly?
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Old 09-30-2007, 11:47 PM   #8
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Quote:
Originally Posted by cjernigan View Post
Depending on what EMS you're using, the megasquirt base maps we have available are pretty damn close for just about any car. Close enough that you could retard the ignition a degree or two extra and bump the fuel a little rich and head down the road with autotune on safely at 7 psi. Atleast that's what I did.
That's what I was planning on doing... I think Brainiack's S60 1.6L will be fairly close to my 1.8L with saab T3. I'll probably hit boost a bit lower, but will run out of steam in the top end so his map would have me pretty dang rich in the upper end. Figured I'd dial back the timing 4-5 degrees, and go to town on it.

Once I get it tuned in "safe" then I'll hit up BEGi for some dyno tuning for power.
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Old 10-01-2007, 12:04 AM   #9
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I am using DIYautotune's timing map with no indicated knock fwiw. Their map is already retarded some from their dynotuned car. As for fuel, it doesn't really matter because you'll be tuning it realtime anyway. Just keep it from going lean.
Man it's cool there are so many going MS.
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Old 10-01-2007, 12:20 AM   #10
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Quote:
just use a reverse helper spring problem solved. With that i was able to run 5 psi on a 12 psi can.
could you explain this alittle more? I assume you mean replacing the spring inside the actuator.
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Old 10-01-2007, 12:32 AM   #11
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No take a spring and clamp it to the rod attach the spring to a plate or something away from the actuator and the force of the spring will pretension the WG allowing you to dial back boost as far as you like.
Name:  04-12-06_1409.jpg
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Old 10-01-2007, 12:42 AM   #12
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Cool. Thanks.
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Old 10-01-2007, 08:55 AM   #13
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Richard I love your "brace" :gay:
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Old 10-01-2007, 03:41 PM   #14
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If you like i can make one for you to i still have the original. lemme know.
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Old 10-01-2007, 04:48 PM   #15
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I for one just think not flooring it is a great idea until your ready to man up and go for >7 psi.
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