3rd Generation Specific (1993-2002) 1993-2002 Discussion including performance modifications and Technical Support Sections.
Sponsored by:

Why did I over boost? 23 psi!!!

Thread Tools
 
Search this Thread
 
Old 01-14-07, 06:08 PM
  #1  
Don't worry be happy...

Thread Starter
iTrader: (1)
 
Montego's Avatar
 
Join Date: Apr 2001
Location: San Diego, CA
Posts: 6,853
Received 793 Likes on 467 Posts
Why did I over boost? 23 psi!!!

BOOM!!! said my motor on Friday night.

This is really disheartning actually. Do all the mods correctly, always make sure that there is enough fuel for the given boost. Yet out of the blue on a cold night I overboost by 13 psi!

Friday night I was taking my friend out to his house. On the on ramp to the freeway I WOT in third (I always do that there). Boost controller set to 10 psi. After the boost kicked and mid way through 3rd my car fell flat on it's face. I knew the car was blown. I cycled to see what my peak boost was and my profecB recorded 22.6 psi! my power FC hit a peak of 17 psi!!! WTF on stock turbos???

I don't get it.

my mods are
Mild Streetport
CAI
PFS SMIC
DP
MP
RB catback
Greedy boost controller
Power FC
STOCK TURBOS
low boost 10 psi
high boost 12 psi.


I always thought i'd be safe as long as I stay near stock levels with stock turbos. Guess not.

Seriously contemplating LS1 after this one. I've been an owner for almost 9 years and it's my second engine under my belt, and fire that totalled my first FD.
Old 01-14-07, 06:19 PM
  #2  
For the win...

iTrader: (3)
 
Rotary4tw's Avatar
 
Join Date: Mar 2005
Location: St. Paul, Minnesota
Posts: 280
Likes: 0
Received 0 Likes on 0 Posts
yikes

Wastegate failure, vaccum hose issue from your EBC install?

Where you doing any work to the car recently to either of those systems that could have caused it?

I think it's safe to safe something in your EBC system failed.

Two things that can save you next time:

1) Run a aftermarket ECU and program it for a "fuel dump" 2 pounds over your high boost. That way if you do overboost you will bog the engine to a rich choke.

2) Install a pop-off valve and set it to 1-2 pounds over your high boost setting. If you overboost, instant vent to atmosphere that cannot fail.

I'm installing my EBC in a few weeks, and this is the exact thing I'm afraid of!

Also, you might want to do a compression check before you consider it blown. 23+ psi is going to blow off any loose vac hoses to the manifold, and if they are off the car is going to run like crap and act blown.

Good luck!

-R4tw
Old 01-14-07, 06:19 PM
  #3  
Senior Member

 
Veger's Avatar
 
Join Date: Aug 2005
Location: UK
Posts: 447
Likes: 0
Received 1 Like on 1 Post
Ouch, makes ya wonder. sorry 2 hear.
Old 01-14-07, 06:20 PM
  #4  
FD / LSX

iTrader: (2)
 
2MCHPWR's Avatar
 
Join Date: Jun 2004
Location: wawayanda, NY
Posts: 1,359
Likes: 0
Received 0 Likes on 0 Posts
sorry to hear.


now join us.
Old 01-14-07, 06:29 PM
  #5  
Full Member

 
sephir0th's Avatar
 
Join Date: Jan 2003
Location: Australia
Posts: 58
Likes: 0
Received 0 Likes on 0 Posts
Wow, sorry to hear.
Hope Rotary4tw is right and your engine isn't blown.

Good luck.
Old 01-14-07, 06:30 PM
  #6  
Rotary Enthusiast

iTrader: (5)
 
Maximum's Avatar
 
Join Date: Mar 2005
Location: Boxford, MA
Posts: 791
Likes: 0
Received 0 Likes on 0 Posts
Was your wastegate ported? Sorry to hear you lost the engine
Old 01-14-07, 06:35 PM
  #7  
Warming the planet.

 
Gadd's Avatar
 
Join Date: Dec 2004
Location: Chico, CA
Posts: 845
Likes: 0
Received 2 Likes on 2 Posts
Is your wastegate ported?
Old 01-14-07, 06:44 PM
  #8  
In the burnout box...

iTrader: (32)
 
mono4lamar's Avatar
 
Join Date: Oct 2003
Location: New York
Posts: 4,453
Likes: 0
Received 1 Like on 1 Post
i wouldnt switch sides over this. you need some fuel upgrades running higher boost. you didnt list upgraded injectors so im assuming your running the stock setup. build a new motor and put some money into everything in that engine bay!

i spent 10 grand over the last winter period with a new motor, all new seals internal and external. went over everthing. its a bit of work having the rotary engine but its pretty cool when you pop your hood absolutely no one knows what they are looking at cause they are used to piston engines.

i guess its easier to have a piston engine but i have much more pride knowing the car is all built right and its got rotors. sorry to hear about your loss. hopefully you figure out what your next move is. good luck
Old 01-14-07, 06:48 PM
  #9  
built not bought

 
bursty's Avatar
 
Join Date: Nov 2005
Location: STL
Posts: 120
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by montego
Seriously contemplating LS1 after this one.
Do it!
Old 01-14-07, 07:01 PM
  #10  
Moderator

iTrader: (7)
 
dgeesaman's Avatar
 
Join Date: May 2002
Location: Fort Kickass
Posts: 12,302
Received 16 Likes on 15 Posts
Definitely sounds like one of the wastegate lines got loose and disabled it.

That's really unfortunate.

Dave
Old 01-14-07, 07:03 PM
  #11  
yea...

 
Rex7-93's Avatar
 
Join Date: Nov 2005
Location: VM
Posts: 318
Likes: 0
Received 0 Likes on 0 Posts
That sucks. Im about to get a rebuilt streeport, on stock turbos run non. seq. hope that doesnt happen. sorry to hear it
Old 01-14-07, 07:10 PM
  #12  
90s riceboy

iTrader: (15)
 
EUROX's Avatar
 
Join Date: Feb 2002
Location: San Diego
Posts: 570
Received 9 Likes on 8 Posts
Sad to hear that, Montego. It's been really cold lately around SD, so I've been wary about driving my car out even though I finally got it together and running after a year. My mods are not so disimilar to yours minus the street port and MP, but I was following the same train of thought that as long as I kept it to around 10 psi, I won't have to worry too much.

Stories like yours are so dispiriting when you hear them.

Which onramp were you on when this happened?
Old 01-14-07, 07:44 PM
  #13  
Sir Braps A lot

 
rx7rcer09's Avatar
 
Join Date: Jul 2006
Location: Hilliard, OHIO
Posts: 2,001
Likes: 0
Received 1 Like on 1 Post
sorry to hear that but dont ls1 it my oppion it kills the purpose of having a RX-7 if its not rotary thats what sets it aside form everything else
Old 01-14-07, 08:05 PM
  #14  
Bann3d. I got OWNED!!!

iTrader: (22)
 
RX7 RAGE's Avatar
 
Join Date: Feb 2001
Location: San Diego, CA
Posts: 5,014
Received 63 Likes on 22 Posts
come back with spinning doritos my friend it must be real disheartening to blow a motor like that though. im gonna make sure my ebc is hooked up right to my full non seq turbos.
Old 01-14-07, 08:33 PM
  #15  
needs more track time

iTrader: (16)
 
gracer7-rx7's Avatar
 
Join Date: Mar 2006
Location: Bay Area CA
Posts: 9,209
Received 515 Likes on 353 Posts
Damn. that sucks. I was just out beating on my car today. Turbos are loving this cool weather.

FWIW, the LS1 route isn't fool proof either. People have been having issues with the welds on the subframes and other parts.
Old 01-14-07, 09:29 PM
  #16  
Rotor Head Extreme

iTrader: (8)
 
t-von's Avatar
 
Join Date: Apr 2002
Location: Midland Texas
Posts: 6,719
Likes: 0
Received 26 Likes on 17 Posts
23psi on stock twins just seems unbelievable. Maybe your boost controller completely malfunctioned.
Old 01-14-07, 09:37 PM
  #17  
Goodfalla Engine Complete

iTrader: (28)
 
Monkman33's Avatar
 
Join Date: May 2005
Location: Kennewick, Washington
Posts: 3,238
Received 32 Likes on 25 Posts
like someone said above, check ALL of your connectors. chances are the pressure popped off a hose or coupler before it got to your engine.

Worth a shot before you write it off as a loss.
Old 01-14-07, 09:58 PM
  #18  
positive

 
negative's Avatar
 
Join Date: Jun 2003
Location: Bay Area, CA
Posts: 592
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Hashiriya
Sad to hear that, Montego. It's been really cold lately around SD, so I've been wary about driving my car out even though I finally got it together and running after a year. My mods are not so disimilar to yours minus the street port and MP, but I was following the same train of thought that as long as I kept it to around 10 psi, I won't have to worry too much.

Stories like yours are so dispiriting when you hear them.

Which onramp were you on when this happened?
What's wrong with cold weather? The dry and cold weather is the best time to drive this car.
Old 01-14-07, 10:48 PM
  #19  
Original Gangster/Rotary!


iTrader: (213)
 
GoodfellaFD3S's Avatar
 
Join Date: Mar 2001
Location: FL-->NJ/NYC again!
Posts: 30,531
Received 539 Likes on 326 Posts
Unhappy

Originally Posted by negative
What's wrong with cold weather? The dry and cold weather is the best time to drive this car.
Colder air is denser, typically the car will make more boost in cooler weather. I've seen swings from as high as 16 psi on a cool morning in one part of NJ to 12 psi on a hot track in anothe part of NJ on the same day. This was with my BNRs w/ported wg and leaving my profeb b on the same setting.

Montego, sucks to hear that that happened to you. Sounds like a wastegate line came loose, if I had to guess. If you want to take the motor out and ship it to NJ, I can rebuild it for you for a pretty good price.
Old 01-14-07, 10:50 PM
  #20  
SINFUL7

iTrader: (37)
 
KaiFD3S's Avatar
 
Join Date: Apr 2004
Location: Alaska
Posts: 6,574
Received 1 Like on 1 Post
daym...sorry to hear Elliot...Stick to the rotor man..dont give up...
Old 01-14-07, 11:23 PM
  #21  
Archie is Gay

 
fsae_alum's Avatar
 
Join Date: Feb 2006
Location: San Diego
Posts: 354
Likes: 0
Received 1 Like on 1 Post
Sorry to hear this man!!! FCKN sucks.

Damn....now I'm worried about driving my car to work tomorrow in 19 degree weather.....
Old 01-14-07, 11:31 PM
  #22  
FD dream is dead

 
apex_sideway's Avatar
 
Join Date: Oct 2003
Location: FL
Posts: 1,691
Received 0 Likes on 0 Posts
Damn, time for a good rebuild

OR

Join the LS1 dark side
Old 01-15-07, 12:15 AM
  #23  
Cheap Bastard

iTrader: (2)
 
adam c's Avatar
 
Join Date: Sep 2002
Location: San Luis Obispo, Ca
Posts: 8,370
Received 50 Likes on 42 Posts
Originally Posted by GoodfellaFD3S
Colder air is denser, typically the car will make more boost in cooler weather. I've seen swings from as high as 16 psi on a cool morning in one part of NJ to 12 psi on a hot track in anothe part of NJ on the same day. This was with my BNRs w/ported wg and leaving my profeb b on the same setting.

Montego, sucks to hear that that happened to you. Sounds like a wastegate line came loose, if I had to guess. If you want to take the motor out and ship it to NJ, I can rebuild it for you for a pretty good price.
Although colder air is denser, we must remember that this is in San Diego, where frigid temps rarely drop below 50 degrees .

Montego, I hope your engine is OK
Old 01-15-07, 01:14 AM
  #24  
No Paypal Accepted!

 
Buzzardsluck's Avatar
 
Join Date: Sep 2005
Location: san antonio, Texas
Posts: 849
Likes: 0
Received 1 Like on 1 Post
Dont make your RX7 into a MX7!
Old 01-15-07, 02:43 AM
  #25  
Call me gramps!

 
WaLieN's Avatar
 
Join Date: Jul 2003
Location: Temecula, CA
Posts: 2,334
Received 0 Likes on 0 Posts
Originally Posted by adam c
Although colder air is denser, we must remember that this is in San Diego, where frigid temps rarely drop below 50 degrees .

Montego, I hope your engine is OK
Some places in SD County were seeing temps in the 20's this weekend! The weather has been nuts here, lately.


Quick Reply: Why did I over boost? 23 psi!!!



All times are GMT -5. The time now is 12:04 AM.