2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.
Sponsored by:

look mom no boost!!

Thread Tools
 
Search this Thread
 
Old 11-26-05, 12:22 PM
  #1  
DONT FEED THE NOOBS

Thread Starter
 
gxlbiscuit's Avatar
 
Join Date: Mar 2001
Location: land of slow hondas .... TULSA, OK
Posts: 1,270
Likes: 0
Received 0 Likes on 0 Posts
look mom no boost!!

I found out my twin scroll has been stuck shut forever..... never stopped me from making boost but i figured it wasnt all taht good for the engine.... i removed the actuator arm and now the car doesnt want to make boost.. i just put my avc-r(boost controller) in and it is maxxed out on the duty.. with the manual controller i wasnt getting any good boost either.. i have a 2.5 exhaust.. the most im hitting right now is umm 11lbs for a few seconds....with the flap closed i could blow up my engine on boost i could run it really high i kept it set at 14 but it would move around never more just would for some reason do less boost. so i took messed with the twin scroll and im worse off.. BNR stage 3

Last edited by gxlbiscuit; 11-26-05 at 12:29 PM.
Old 11-26-05, 12:24 PM
  #2  
Banned. I got OWNED!!!
 
--MAstermind--'s Avatar
 
Join Date: May 2004
Location: San Antonio
Posts: 778
Likes: 0
Received 0 Likes on 0 Posts
if its a stock S4 its not gunna run right unless u get ur twinscroll back....OR u port ur turbos wastegate and up the boost i hear if u modd the stock turbo config u can eliminate the twinscroll after upping the boost and performance...i dunno though could even be sumthing else!
Old 11-26-05, 12:30 PM
  #3  
DONT FEED THE NOOBS

Thread Starter
 
gxlbiscuit's Avatar
 
Join Date: Mar 2001
Location: land of slow hondas .... TULSA, OK
Posts: 1,270
Likes: 0
Received 0 Likes on 0 Posts
bnr stage 3
Old 11-26-05, 12:33 PM
  #4  
IFO Forced Induction Slo

iTrader: (3)
 
bigdv519's Avatar
 
Join Date: Mar 2004
Location: Houston
Posts: 1,315
Likes: 0
Received 0 Likes on 0 Posts
He has a bnr stage 3, not a stock turbo.

Let me see if I understand correctly. It's slightly difficult to understand what your trying to explain.

You made boost WITH the twin scroll flapper in the shut position. OK. Then you removed JUST THE ARM for the twin scroll and now you make less boost?
Old 11-26-05, 12:39 PM
  #5  
DONT FEED THE NOOBS

Thread Starter
 
gxlbiscuit's Avatar
 
Join Date: Mar 2001
Location: land of slow hondas .... TULSA, OK
Posts: 1,270
Likes: 0
Received 0 Likes on 0 Posts
yes i dissconnected the actuator arm for the twin scroll so it is always open. now i get less boost.. the car was faster with the scroll shut
Old 11-26-05, 12:44 PM
  #6  
Rx-hippie

iTrader: (1)
 
trainwreck517's Avatar
 
Join Date: Sep 2003
Location: Torrance CA
Posts: 2,076
Likes: 0
Received 0 Likes on 0 Posts
Hmm, are you sure you didn't disconnect the waste gate instead by accident? Leaving the wastegate open all the time?

Just a thought.
Old 11-26-05, 12:47 PM
  #7  
DONT FEED THE NOOBS

Thread Starter
 
gxlbiscuit's Avatar
 
Join Date: Mar 2001
Location: land of slow hondas .... TULSA, OK
Posts: 1,270
Likes: 0
Received 0 Likes on 0 Posts
im very sure
Old 11-26-05, 12:52 PM
  #8  
IFO Forced Induction Slo

iTrader: (3)
 
bigdv519's Avatar
 
Join Date: Mar 2004
Location: Houston
Posts: 1,315
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by gxlbiscuit
yes i dissconnected the actuator arm for the twin scroll so it is always open. now i get less boost.. the car was faster with the scroll shut
Ok, I got some more questions.

What is the normal max boost you run? At what rpms does it start to "fall off"?

Edit: Also, with the scroll shut, what rpms did you achieve full boost? Now with the scroll open, when does boost begin to build, and peak?

Last edited by bigdv519; 11-26-05 at 12:55 PM.
Old 11-26-05, 12:56 PM
  #9  
Banned. I got OWNED!!!
 
--MAstermind--'s Avatar
 
Join Date: May 2004
Location: San Antonio
Posts: 778
Likes: 0
Received 0 Likes on 0 Posts
OOoooOOH now tahts just wierd....OOPs...sorry yea i thought it might be the wastegate purging all the boost
Old 11-26-05, 01:27 PM
  #10  
Alcohol Fueled!

iTrader: (2)
 
J-Rat's Avatar
 
Join Date: Jan 2002
Location: Hood River oregon
Posts: 11,093
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by gxlbiscuit
yes i dissconnected the actuator arm for the twin scroll so it is always open. now i get less boost.. the car was faster with the scroll shut
Of course it works this way.. I could have told you this. Disconnecting the twin scroll actuator will make a stock S4 turbo boost slower, THEN add that its a HYbrid? Yep, you lost alot of spool! Is the scroll control system still intact?
Old 11-26-05, 01:29 PM
  #11  
DONT FEED THE NOOBS

Thread Starter
 
gxlbiscuit's Avatar
 
Join Date: Mar 2001
Location: land of slow hondas .... TULSA, OK
Posts: 1,270
Likes: 0
Received 0 Likes on 0 Posts
its wierd ill set the boost to 14 cuz it will spike to that at 4500 but settle back down to 11ish by the time im supposed to shift.. current boost im not sure cuz my datalogger is being an ***. my manual boost gauge shows at 11lbs but its only in one specific gear and not all the time... THEN other gears itll got to 12 and then back down. i want it to go to a set boost and stay there dag gone it. thats why i bought the avc-r. im going to dissable the gear senstive boost cuz i need a new speedo cable(the speed jumps around on the screen. soo my gear judge may be off. i need to get my exhaust remade to 3 inch before the Y.

Last edited by gxlbiscuit; 11-26-05 at 01:32 PM.
Old 11-26-05, 01:36 PM
  #12  
DONT FEED THE NOOBS

Thread Starter
 
gxlbiscuit's Avatar
 
Join Date: Mar 2001
Location: land of slow hondas .... TULSA, OK
Posts: 1,270
Likes: 0
Received 0 Likes on 0 Posts
yes its all intact.. my turbo builder said to take that crap out i have seen other people do it.... i would think since it a hybird too it would need that.. but the fact that the car was faster with the actuator ALWAYS shut is still odd... and the exhaust onthe turbo has been port matched
Old 11-26-05, 01:40 PM
  #13  
Haven't we ALL heard this

 
Wankel7's Avatar
 
Join Date: Mar 2001
Location: Indiana
Posts: 3,948
Likes: 0
Received 1 Like on 1 Post
When I got my manifold/bnr 3 from bnr the twin scroll was removed complety.

James
Old 11-26-05, 01:49 PM
  #14  
Alcohol Fueled!

iTrader: (2)
 
J-Rat's Avatar
 
Join Date: Jan 2002
Location: Hood River oregon
Posts: 11,093
Likes: 0
Received 2 Likes on 2 Posts
Mine is gone because I ran an S5 turbo and manifold.
Old 11-26-05, 02:14 PM
  #15  
DONT FEED THE NOOBS

Thread Starter
 
gxlbiscuit's Avatar
 
Join Date: Mar 2001
Location: land of slow hondas .... TULSA, OK
Posts: 1,270
Likes: 0
Received 0 Likes on 0 Posts
i just think it would be DUMB to install the flap to where its always shut again....
Old 11-26-05, 02:36 PM
  #16  
7th Heaven

iTrader: (9)
 
slpin's Avatar
 
Join Date: Nov 2004
Location: California
Posts: 3,654
Likes: 0
Received 1 Like on 1 Post
Originally Posted by trainwreck517
Hmm, are you sure you didn't disconnect the waste gate instead by accident? Leaving the wastegate open all the time?

Just a thought.
wrong thought
it would be even faster if he disconnected the wastegate
Old 11-26-05, 02:38 PM
  #17  
7th Heaven

iTrader: (9)
 
slpin's Avatar
 
Join Date: Nov 2004
Location: California
Posts: 3,654
Likes: 0
Received 1 Like on 1 Post
it spools faster faster because that was what the system is designed... all the gas is forced thru 1 runner,, makign ti spin faster

but then.... at high rpm,t i will choke itself if it doesnt open up
Old 11-26-05, 02:44 PM
  #18  
DONT FEED THE NOOBS

Thread Starter
 
gxlbiscuit's Avatar
 
Join Date: Mar 2001
Location: land of slow hondas .... TULSA, OK
Posts: 1,270
Likes: 0
Received 0 Likes on 0 Posts
umm not really id didnt seem to choke BUT i cant see holding a flap infront of the exhaust good for backpressure on the engine.. i mean the choking
Old 11-26-05, 07:36 PM
  #19  
DONT FEED THE NOOBS

Thread Starter
 
gxlbiscuit's Avatar
 
Join Date: Mar 2001
Location: land of slow hondas .... TULSA, OK
Posts: 1,270
Likes: 0
Received 0 Likes on 0 Posts
i put the actuator arm back on.. the actuator is actually broken and not moving... adn the ca ris faster with the twin scroll stuck...

Last edited by gxlbiscuit; 11-26-05 at 07:58 PM.
Old 11-26-05, 10:17 PM
  #20  
Rx-hippie

iTrader: (1)
 
trainwreck517's Avatar
 
Join Date: Sep 2003
Location: Torrance CA
Posts: 2,076
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by slpin
wrong thought
it would be even faster if he disconnected the wastegate

Why is that? With the waste gate open at all rpms. The exhuast gas will by pass the turbine and get dumped right into the exhuast. Which will result in very little to no boost. Which is the symtom he discribed.

But he already made sure it wasn't the wastegate he dissconnected, so it wouldn't be the case in his situation.

And if your not building boost with the twin scroll removed/open.. then there is something wrong with your turbo. It would take longer to boost, perhaps 1k -2k rpm different compared to working system.

I would double check that the wastegate is operating correctly, closing all the way and opening only at desired boost, grab a air pump and pressure guage and pump it up to your set boost and see if it opens. Pump air into the boost controler/wastegate actualator.
Old 11-26-05, 11:14 PM
  #21  
7th Heaven

iTrader: (9)
 
slpin's Avatar
 
Join Date: Nov 2004
Location: California
Posts: 3,654
Likes: 0
Received 1 Like on 1 Post
Originally Posted by trainwreck517
Why is that? With the waste gate open at all rpms. The exhuast gas will by pass the turbine and get dumped right into the exhuast. Which will result in very little to no boost. Which is the symtom he discribed.

But he already made sure it wasn't the wastegate he dissconnected, so it wouldn't be the case in his situation.

And if your not building boost with the twin scroll removed/open.. then there is something wrong with your turbo. It would take longer to boost, perhaps 1k -2k rpm different compared to working system.

I would double check that the wastegate is operating correctly, closing all the way and opening only at desired boost, grab a air pump and pressure guage and pump it up to your set boost and see if it opens. Pump air into the boost controler/wastegate actualator.

if he unhook the wastegate line
it stays SHUT
pressure opens the gate
unhooked = no pressure
Old 11-27-05, 12:06 AM
  #22  
Rx-hippie

iTrader: (1)
 
trainwreck517's Avatar
 
Join Date: Sep 2003
Location: Torrance CA
Posts: 2,076
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by slpin
if he unhook the wastegate line
it stays SHUT
pressure opens the gate
unhooked = no pressure
He said he unhooked the rod, not the vac/boost line. If he unhooked the line.. then there would be massive boost leak.

If he unhooked the rod, the wastegate will open with any exhuast flow.
Old 11-27-05, 12:46 AM
  #23  
Sharp Claws

iTrader: (30)
 
RotaryEvolution's Avatar
 
Join Date: Oct 2003
Location: Central Florida
Posts: 5,107
Likes: 0
Received 41 Likes on 40 Posts
quit it children, no one specified rod or vacuum line and the title was a bit misleading so i'm not gonna read through everything.
Old 11-27-05, 01:14 AM
  #24  
Banned. I got OWNED!!!
 
FB II's Avatar
 
Join Date: Dec 2002
Location: wishing i was back in FL
Posts: 4,192
Likes: 0
Received 0 Likes on 0 Posts
that twin scroll junk should not be an issue. i had a TII turbo on a stock port 12a and it made full boost by 3500rpms... no actuator in sight, the hole welded shut. i think your wastegate is pissed off.
Old 11-27-05, 03:26 AM
  #25  
DONT FEED THE NOOBS

Thread Starter
 
gxlbiscuit's Avatar
 
Join Date: Mar 2001
Location: land of slow hondas .... TULSA, OK
Posts: 1,270
Likes: 0
Received 0 Likes on 0 Posts
ill start checking it again.. but i put my twin scroll actuator back together to find out the actuator is jammed shut.... so i i tuned the boost controller to run with it normal (the broken twin scroll always has been shut didnt know till now) the car si freaking fast keep in mind that the turbine inlet is matchported.. the car screams... i so badly wanted to embarass some fd but i didnt want another ticket...... 14lbs on bnr stage 3 .. i think my wastegate is holdin up just fine...
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Shainiac
Single Turbo RX-7's
12
07-17-19 02:20 PM
Jeff20B
1st Generation Specific (1979-1985)
73
09-16-18 07:16 PM
Bauer778
3rd Generation Specific (1993-2002)
10
11-04-15 04:42 PM
zxrazorxz
3rd Generation Specific (1993-2002)
2
09-14-15 07:21 PM
High_Carb_Diet
Power FC Forum
1
09-05-15 09:07 AM



Quick Reply: look mom no boost!!



All times are GMT -5. The time now is 09:17 AM.