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boost problem

Old Sep 4, 2002 | 08:19 PM
  #1  
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heres the problem: i can't keep the 20b in boost at redline, it was actually so bad that the blowoffs would dump, before you let off the gas. part of the problem was an airfilter that was sucked shut , that has been fixed.

heres the info: the stock 20b boosts to 9 psi on the first tubo and about 7 on the second. mine will spike to 9 and then gradually fall off to about 3-4psi. the only non stock parts are the following: racing beat turbo back exhaust, at 3" and then 2.5" after the y its identical to the stock 20b exhaust, except for the cats.

the greddy fmic: its the old school one with the 60mm piping, the stock cosmo piping is the same as an fd 2.75".



any suggestions how to proceed would be helpful



mike
Old Sep 4, 2002 | 10:48 PM
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stock ecu?
Old Sep 4, 2002 | 11:06 PM
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Originally Posted by j9fd3s' date='Sep 4 2002, 06:19 PM
heres the problem: i can't keep the 20b in boost at redline, it was actually so bad that the blowoffs would dump, before you let off the gas. part of the problem was an airfilter that was sucked shut , that has been fixed.

heres the info: the stock 20b boosts to 9 psi on the first tubo and about 7 on the second. mine will spike to 9 and then gradually fall off to about 3-4psi. the only non stock parts are the following: racing beat turbo back exhaust, at 3" and then 2.5" after the y its identical to the stock 20b exhaust, except for the cats.

the greddy fmic: its the old school one with the 60mm piping, the stock cosmo piping is the same as an fd 2.75".



any suggestions how to proceed would be helpful



mike
You're not running them in parallel?
Old Sep 5, 2002 | 10:19 AM
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they are parallel, and the ecu is an e6k. i think i fixed most of it, but it now holds .3 at redline.



mike
Old Sep 5, 2002 | 12:13 PM
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Originally Posted by j9fd3s' date='Sep 5 2002, 08:19 AM
they are parallel, and the ecu is an e6k. i think i fixed most of it, but it now holds .3 at redline.



mike
Oh, I didn't read the post carefully enough. Did you leave any of that turbo control crap on the motor? Have you tried wiring the wastegate shut?
Old Sep 5, 2002 | 12:35 PM
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Originally Posted by 13BAce' date='Sep 5 2002, 10:13 AM
[quote name='j9fd3s' date='Sep 5 2002, 08:19 AM']they are parallel, and the ecu is an e6k. i think i fixed most of it, but it now holds .3 at redline.



mike
Oh, I didn't read the post carefully enough. Did you leave any of that turbo control crap on the motor? Have you tried wiring the wastegate shut?[/quote]

none of the control stuff is left, i'm thinking that maybe the intercooler, or exhaust is too restrictive. i put my boost guage right on the turbo and its at about 11 while the intake is at 8. it could also be that the exhaust is too small?



mike
Old Sep 5, 2002 | 03:59 PM
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Originally Posted by j9fd3s' date='Sep 5 2002, 10:35 AM
[quote name='13BAce' date='Sep 5 2002, 10:13 AM'][quote name='j9fd3s' date='Sep 5 2002, 08:19 AM']they are parallel, and the ecu is an e6k. i think i fixed most of it, but it now holds .3 at redline.



mike
Oh, I didn't read the post carefully enough. Did you leave any of that turbo control crap on the motor? Have you tried wiring the wastegate shut?[/quote]

none of the control stuff is left, i'm thinking that maybe the intercooler, or exhaust is too restrictive. i put my boost guage right on the turbo and its at about 11 while the intake is at 8. it could also be that the exhaust is too small?



mike[/quote]

You've got some sort of bottleneck. Are you sure there are no leaks anywhere?
Old Sep 6, 2002 | 01:11 PM
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Originally Posted by 13BAce' date='Sep 5 2002, 01:59 PM
[quote name='j9fd3s' date='Sep 5 2002, 10:35 AM'][quote name='13BAce' date='Sep 5 2002, 10:13 AM'][quote name='j9fd3s' date='Sep 5 2002, 08:19 AM']they are parallel, and the ecu is an e6k. i think i fixed most of it, but it now holds .3 at redline.



mike
Oh, I didn't read the post carefully enough. Did you leave any of that turbo control crap on the motor? Have you tried wiring the wastegate shut?[/quote]

none of the control stuff is left, i'm thinking that maybe the intercooler, or exhaust is too restrictive. i put my boost guage right on the turbo and its at about 11 while the intake is at 8. it could also be that the exhaust is too small?



mike[/quote]

You've got some sort of bottleneck. Are you sure there are no leaks anywhere?[/quote]

there could be something still, but i doubt it. it now goes to .5 and it will stay at about .4 til redline, which is ok, .7 was way more fun.....



mike
Old Sep 6, 2002 | 01:36 PM
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Originally Posted by j9fd3s' date='Sep 6 2002, 11:11 AM
[quote name='13BAce' date='Sep 5 2002, 01:59 PM'][quote name='j9fd3s' date='Sep 5 2002, 10:35 AM'][quote name='13BAce' date='Sep 5 2002, 10:13 AM'][quote name='j9fd3s' date='Sep 5 2002, 08:19 AM']they are parallel, and the ecu is an e6k. i think i fixed most of it, but it now holds .3 at redline.



mike
Oh, I didn't read the post carefully enough. Did you leave any of that turbo control crap on the motor? Have you tried wiring the wastegate shut?[/quote]

none of the control stuff is left, i'm thinking that maybe the intercooler, or exhaust is too restrictive. i put my boost guage right on the turbo and its at about 11 while the intake is at 8. it could also be that the exhaust is too small?



mike[/quote]

You've got some sort of bottleneck. Are you sure there are no leaks anywhere?[/quote]

there could be something still, but i doubt it. it now goes to .5 and it will stay at about .4 til redline, which is ok, .7 was way more fun.....



mike[/quote]

Check all of the couplers before you start digging into anything serious.
Old Sep 6, 2002 | 04:33 PM
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Originally Posted by 13BAce' date='Sep 6 2002, 11:36 AM
[quote name='j9fd3s' date='Sep 6 2002, 11:11 AM'][quote name='13BAce' date='Sep 5 2002, 01:59 PM'][quote name='j9fd3s' date='Sep 5 2002, 10:35 AM'][quote name='13BAce' date='Sep 5 2002, 10:13 AM'][quote name='j9fd3s' date='Sep 5 2002, 08:19 AM']they are parallel, and the ecu is an e6k. i think i fixed most of it, but it now holds .3 at redline.



mike
Oh, I didn't read the post carefully enough. Did you leave any of that turbo control crap on the motor? Have you tried wiring the wastegate shut?[/quote]

none of the control stuff is left, i'm thinking that maybe the intercooler, or exhaust is too restrictive. i put my boost guage right on the turbo and its at about 11 while the intake is at 8. it could also be that the exhaust is too small?



mike[/quote]

You've got some sort of bottleneck. Are you sure there are no leaks anywhere?[/quote]

there could be something still, but i doubt it. it now goes to .5 and it will stay at about .4 til redline, which is ok, .7 was way more fun.....



mike[/quote]

Check all of the couplers before you start digging into anything serious.[/quote]

yup, i have one with 2 clamps on it, and it still isn't happy, but its getting replaced soon



mike

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