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

help ahh!! too much boost 14 psi!

Thread Tools
 
Search this Thread
 
Old 06-12-05, 03:49 PM
  #1  
I

Thread Starter
iTrader: (6)
 
KompressorLOgic's Avatar
 
Join Date: May 2004
Location: Spanaway, WA
Posts: 3,755
Received 12 Likes on 12 Posts
help ahh!! too much boost 14 psi!

ok i have a 87 turbo II, ive read threw some things but havnt found a steady opinion...

on my 87 turbo II i have a full 3" exhaust, and the TID mod, and an FCON, and last nite i was hitting 14 psi at the top of 3rd gear. and i allready know thats TOOO MUCH!!!

some questions i have are
1. what is the max boost i can run on stock turbo safly?
2. could i use a manual boost controllor to limit this boost to a safe level??
or do i have to port the waste gate?

now im going to install a walbro 255 this week cause i understand stock fuel pump isnt addiquit sp?.

now what do you think is the highest boost i can run on stock 550 CC with upgraded pump and hte FCON PFC???

im either gonna keep the fcon or get a rtek 1.7 with the 720 CC and whats the highest level i can run on that setup??
Old 06-12-05, 03:57 PM
  #2  
Passing life by

 
iceblue's Avatar
 
Join Date: Feb 2005
Location: Scotland, USA
Posts: 4,028
Likes: 0
Received 2 Likes on 2 Posts
a MBC will only raise boost. You need a closed loop EBC boost controller like a apexi AFC-R. 12psi on stock turbo and IC. You need to have your timing retarded. You need a FCD as you obveiusly have I dont know maybe your fcon does that. The Rtek chip has one built in. The 720cc secondarys are kind of needed for that kind of power. You need to port your waste gate to.
Old 06-12-05, 04:28 PM
  #3  
Rotary Enthusiast


iTrader: (5)
 
Net Seven's Avatar
 
Join Date: Apr 2002
Location: Mesa, AZ
Posts: 1,470
Received 15 Likes on 11 Posts
Type-R spoiler should solve all your problems while increasing the quality of the idle on your ROTARY engine.
Old 06-12-05, 04:36 PM
  #4  
Passing life by

 
iceblue's Avatar
 
Join Date: Feb 2005
Location: Scotland, USA
Posts: 4,028
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by Net Seven
Type-R spoiler should solve all your problems while increasing the quality of the idle on your ROTARY engine.
Old 06-12-05, 04:46 PM
  #5  
RIP Icemark

iTrader: (4)
 
Tournapart's Avatar
 
Join Date: May 2005
Location: Mesa, AZ
Posts: 1,019
Likes: 0
Received 2 Likes on 2 Posts
lol
Old 06-12-05, 06:18 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
YOu need to port your wastegate, boost controler is used to raise boost, not lower it.

And I wouldn't run more then 10psi on stock injectors, and no more then 12psi on stock turbo and TMIC. Anything over 12psi on stock turbo and intercooler and your going to be running way to hot, so you will be making same power at 12 then you would at 14psi.
Old 06-12-05, 07:11 PM
  #7  
Full Member

 
13bturbo2's Avatar
 
Join Date: Jun 2004
Location: Panama City, Panama
Posts: 215
Likes: 0
Received 0 Likes on 0 Posts
how are you even hitting 14psi? are you sure you're reading your gauge right? as of now if you are running that much with "above" stock mods, then your engine is looking towards early retirement.
Old 06-12-05, 07:20 PM
  #8  
Rest In Peace Dave

 
bcool's Avatar
 
Join Date: Feb 2004
Location: Idaho
Posts: 1,347
Likes: 0
Received 0 Likes on 0 Posts
The stock boost gauge isnt that accurate to begin with, but anyways you need to get your problem fixed before you blow your motor. Port your wastegate, you are running a very open intake and exhuast setup right now and that will cause problems with boost creep. BTW if you wanna run 10 PSI i strongly reccomend bigger fuel pump/injectors anyways. And really, anything above 10psi on the stock S4 turbo is just acting like a hairdryer.
Old 06-12-05, 08:26 PM
  #9  
I

Thread Starter
iTrader: (6)
 
KompressorLOgic's Avatar
 
Join Date: May 2004
Location: Spanaway, WA
Posts: 3,755
Received 12 Likes on 12 Posts
thanx for your guys inputs!!! needed some clarification
i have an aftermarket gauge, and yes my exhaust is basicly straight 3" to the tip, RB downpipe to 3" high flow cat which my other car hollowed out for me and 3" CS catback


i will plan to port the waste gate and install the walbro 255 this wednesday, then hopefully boost shouldnt pass 10, if it still does then im gonna save up for the rtek and injectors
Old 06-12-05, 08:32 PM
  #10  
Passing life by

 
iceblue's Avatar
 
Join Date: Feb 2005
Location: Scotland, USA
Posts: 4,028
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by kompressorlogic
thanx for your guys inputs!!! needed some clarification
i have an aftermarket gauge, and yes my exhaust is basicly straight 3" to the tip, RB downpipe to 3" high flow cat which my other car hollowed out for me and 3" CS catback


i will plan to port the waste gate and install the walbro 255 this wednesday, then hopefully boost shouldnt pass 10, if it still does then im gonna save up for the rtek and injectors
That will all help and may work for you. But you still wont be able to controll boost or creep without a closed loop EBC controller.
Old 06-13-05, 05:53 AM
  #11  
I'm a boost creep...

 
NZConvertible's Avatar
 
Join Date: Jan 2002
Location: Auckland, New Zealand
Posts: 15,608
Likes: 0
Received 8 Likes on 8 Posts
Originally Posted by iceblue
a MBC will only raise boost. You need a closed loop EBC boost controller like a apexi AFC-R.
That's complete BS. An EBC is no more capable of lowering boost than a MBC. Boost creep is purely about wastegate flow (not enough of it), and no boost controller in the world can fix that.

kompressorlogic, you have to port the wastegate. Don't just port to the edge of the stock flap either, you'll still get creep with your mods. Fit a bigger flap and make the port as large as possible.
Old 06-13-05, 03:44 PM
  #12  
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 NZConvertible
That's complete BS. An EBC is no more capable of lowering boost than a MBC. Boost creep is purely about wastegate flow (not enough of it), and no boost controller in the world can fix that.

He is just regurgitating what he learned from Uncle Ted.
Old 06-13-05, 04:10 PM
  #13  
I live in an igloo

 
BlaCkPlaGUE's Avatar
 
Join Date: Jul 2004
Location: calgary alberta
Posts: 2,546
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by J-Rat
He is just regurgitating what he learned from Uncle Ted.
I doubt reted would ever say that, that is if your referring to him. I think a better statement would be
"i think he just pulled it out of his ***"
Old 06-13-05, 04:42 PM
  #14  
- Make Haste -

 
Archangels's Avatar
 
Join Date: Apr 2005
Location: Calgary, Alberta
Posts: 1,648
Likes: 0
Received 0 Likes on 0 Posts
i have the exact mods as you and i spike at 15psi, yes thats way too much, i dont have fuel mods either, but i dont hurt anything....

i just dont push it that hard because intake temps will be wayyy too hot....
Old 06-13-05, 05:00 PM
  #15  
Passing life by

 
iceblue's Avatar
 
Join Date: Feb 2005
Location: Scotland, USA
Posts: 4,028
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by NZConvertible
That's complete BS. An EBC is no more capable of lowering boost than a MBC. Boost creep is purely about wastegate flow (not enough of it), and no boost controller in the world can fix that.

kompressorlogic, you have to port the wastegate. Don't just port to the edge of the stock flap either, you'll still get creep with your mods. Fit a bigger flap and make the port as large as possible.
Acording to ReTed you can sustain a boost with a EBC controller.

If you take note to where I stated waste gate must be ported as well to prevent the creeping.
Old 06-13-05, 05:08 PM
  #16  
I break Diff mounts

iTrader: (1)
 
Digi7ech's Avatar
 
Join Date: Jun 2002
Location: Avondale, Arizona
Posts: 4,403
Likes: 0
Received 4 Likes on 2 Posts
With your mods I can easily see hitting 14psi as being realistic.

With 2.5 dp and silencer to CS 3 single I would hit 12psi on a S5 wastegate.

Port the living **** out of it if it's a S4 turbo. If it's S5 you can half *** it and it will still be better.

By porting it you will need to increase it to a hole way bigger than the stock flapper door. Then weld on a small washer/circular piece of metal to cover the newly enlarged hole.

People say 10psi is the limit of safe psi on stock injectors. I have hit 15psi a few time by accident and my engine is still living. At those upper psi ranges your maxing out the injectors and your also getting ready to spin the turbo out of it's safe and efficient range.

Usually 14+psi will just create **** loads of heat and destroy the turbo prematurely.
///

So. Port the wastegate/get some 720's/get a boost controller and a Rtek and you'll be set to run 12psi daily.
Old 06-14-05, 03:29 AM
  #17  
I'm a boost creep...

 
NZConvertible's Avatar
 
Join Date: Jan 2002
Location: Auckland, New Zealand
Posts: 15,608
Likes: 0
Received 8 Likes on 8 Posts
Originally Posted by iceblue
Acording to ReTed you can sustain a boost with a EBC controller.
Yes you can, but "sustaining" boost and "lowering" boost mean totally different things, in fact in this case they mean the exact opposite.

If you take note to where I stated waste gate must be ported as well to prevent the creeping.
That doesn't make your statement any less wrong.
Old 06-14-05, 03:50 AM
  #18  
Lives on the Forum

 
RETed's Avatar
 
Join Date: Feb 2001
Location: n
Posts: 26,664
Likes: 0
Received 16 Likes on 15 Posts
Originally Posted by iceblue
Acording to ReTed you can sustain a boost with a EBC controller.
Doh!


-Ted
Old 06-14-05, 04:01 AM
  #19  
I am 2Furious

 
gingenhagen's Avatar
 
Join Date: Sep 2004
Location: NJ / Philly
Posts: 846
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by trainwreck517
YOu need to port your wastegate, boost controler is used to raise boost, not lower it.

And I wouldn't run more then 10psi on stock injectors, and no more then 12psi on stock turbo and TMIC. Anything over 12psi on stock turbo and intercooler and your going to be running way to hot, so you will be making same power at 12 then you would at 14psi.
Would I be correct in saying that an upgraded fuel pump in a sense "upgrades" the fuel injectors, so that I could run 12 PSI with say a walboro?

Originally Posted by J-Rat
He is just regurgitating what he learned from Uncle Ted.
Meh. A lot of my posts are regurgitations. Can't do much with my knowledge besides answer those easy questions that I've heard answered numerous times already.
Old 06-14-05, 12:50 PM
  #20  
I break Diff mounts

iTrader: (1)
 
Digi7ech's Avatar
 
Join Date: Jun 2002
Location: Avondale, Arizona
Posts: 4,403
Likes: 0
Received 4 Likes on 2 Posts
Originally Posted by gingenhagen
Would I be correct in saying that an upgraded fuel pump in a sense "upgrades" the fuel injectors, so that I could run 12 PSI with say a walboro?
To an extent yes, but you don't know how much unless you have AFR readings and fuel pressure numbers.

I noitced that my fuel pressure was around 50psi with the walbro. I think stock is 40psi.
Old 06-14-05, 01:54 PM
  #21  
Rotary Freak

 
Bukwild's Avatar
 
Join Date: Apr 2003
Location: DC Area
Posts: 2,702
Likes: 0
Received 1 Like on 1 Post
take it to a dyno and get some AFR numbers before you pop your motor. If you are not going to spend alot of money on what it takes to run 14lbs of boost then be happy with 8-10lbs safely. Or learn to rebuild rotaries
Old 06-14-05, 06:29 PM
  #22  
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 iceblue
a MBC will only raise boost. You need a closed loop EBC boost controller like a apexi AFC-R. 12psi on stock turbo and IC. You need to have your timing retarded. You need a FCD as you obveiusly have I dont know maybe your fcon does that. The Rtek chip has one built in. The 720cc secondarys are kind of needed for that kind of power. You need to port your waste gate to.

wrong
he does not need closed loop ebc.
with the wastegate acutator open as much as it could (stock setup) he is getting 14psi.
no type of boost controller in the world would fix that.
f-con does not do fuel cut unless he has the FCD with it.
with 14psi, he should already have a fcd - how else would he get to 14psi?
also

wth is a EBC boost controller.

electric boost controller boost controller makes no sense
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
24seven_dada
3rd Generation Specific (1993-2002)
20
11-10-18 12:03 PM
Jeff20B
1st Generation Specific (1979-1985)
73
09-16-18 07:16 PM
Clacor
Single Turbo RX-7's
19
09-11-15 08:36 PM
High_Carb_Diet
Power FC Forum
1
09-05-15 09:07 AM



Quick Reply: help ahh!! too much boost 14 psi!



All times are GMT -5. The time now is 02:20 AM.