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Old 08-25-2009, 03:37 PM   #1
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Default BEGi seperated gas Downpipe, Wastegate opening enough?

So with my wategate actuator rod completely disconnected I am still building quite a bit of boost.
Earlier today I was able to brake boost it to like 8psi
So Corky was telling me how sometimes a spacer is needed on the DP flange because the wastegate is not able to open far enough, but by the looks of it my wategate is able to open pretty far.

Closed:
IMGP3491_sm.jpg

Opened:
IMGP3492_sm.jpg

Better view of it opened:
IMGP3493_sm.jpg

Does that look like is opened enough?
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Old 08-25-2009, 03:40 PM   #2
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needs a longer shaft and SS feed, stat.
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Old 08-25-2009, 03:58 PM   #3
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Porting the wastegate helps reduce/eliminate boost creep. A lot!
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Old 08-25-2009, 04:24 PM   #4
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Im considering just converting it to a dump tube...
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Old 08-25-2009, 04:32 PM   #5
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Compared to the FM and BEGI turbo offerings of 8-12 years ago the manifolds and exhausts are so much more efficient that they will make boost with a very open wastegate.

As others said, porting the wastegate hole in the turbine housing will help - and so would a larger hotside a/r lol.

What's the rest of your setup? (Exhaust, cam timing etc)
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Old 08-25-2009, 04:48 PM   #6
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Its a 99, stock long block, exhaust cam is retarded a tooth (happened when i saw spraying nitrous and i still havent fixed it, haha)
Its a BEGi Shanghai-S kit, non-intercooled. I have a racing beat race mid pipe and racing beat single tip muffler.
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Old 08-25-2009, 07:14 PM   #7
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Retarded exhaust cam will give you extra energetic exhaust gas.
Fix that and your 'gate open boost will come down.
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Old 08-26-2009, 01:50 PM   #8
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Quote:
Originally Posted by JasonC SBB View Post
Retarded exhaust cam will give you extra energetic exhaust gas.
Fix that and your 'gate open boost will come down.
I cannot beleive I totally overlooked the implications of the exhaust cam timing until now.
I can imagine that the increased overlap combined with my current pig rich AFR's would probably create a very hot and energetic condition within the exhaust manifold.

Im gonna get on fixing that first
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Old 08-26-2009, 03:43 PM   #9
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Quote:
Originally Posted by JasonC SBB View Post
Compared to the FM and BEGI turbo offerings of 8-12 years ago the manifolds and exhausts are so much more efficient that they will make boost with a very open wastegate.


Your exhuast takes the path of least resistance. You're trying to push all your exhaust gas through a quarter sized hole. Some of it is bound to make it through the turbine. An external wg would be better but still not 100% efficient.
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Old 08-26-2009, 04:23 PM   #10
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sdasdasdasd
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File Type: jpg IMG00001-20090826-1509.jpg (98.7 KB, 201 views)
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Old 08-26-2009, 04:42 PM   #11
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The spacer helped on your shanghai setup?
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Old 08-26-2009, 05:10 PM   #12
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yeah, the flapper door was banging the dp.
the flapper arm would open more with the DP off than it would on.

now i am having a problem like phils first problem where the flapper gets stuck, i need to put a C-clip on it like he did.
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Old 08-28-2009, 06:21 PM   #13
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Quote:
Originally Posted by sprayed View Post


Your exhuast takes the path of least resistance. You're trying to push all your exhaust gas through a quarter sized hole. Some of it is bound to make it through the turbine. An external wg would be better but still not 100% efficient.
What are you jerking off about? I agree with your sentences above. But, with a more efficient i/c and a more efficient manifold, it will make more boost with the quarter sized hole you mentioned, uncovered.

I upgraded from an AVO setup to the BEGI separated setup with no other change and found a stronger topend and that the new setup would make 4-5 psi boost with the wastegate disconnected (it used to make 3 psi). Like the OP, the wastegate was free to open.


BTW to the OP, I should have said with an ADVANCED exhaust cam you will get much more energy in the exhaust. You probably have it backwards, your exahust is opening sooner.
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Old 08-28-2009, 07:20 PM   #14
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Yah, I thought it was retarded but I may be wrong.

I wouldnt have any issue with 4-5 psi when the wastegate is completely opened, but currently with it completely disconnected It keeps on going up until I get detonation.

Im going to see if Corky will send me a spacer like what tyson has, if that doenst work Im converting it to an external dump (as in, the wastegate outlet doenst feed back into the dowpipe, it just dumps), and if that still doenst fix it Ill port the wastegate...
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