boost spike... help!
#1
Junior Member
Thread Starter
Join Date: Aug 2003
Location: Ottawa, Canada
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
boost spike... help!
I just installed an HKS downpipe and now I have a boost spike when the secondary comes online.
I have an apex'i N1 dual exhaust but still have the stock cats.
Is there anything I can do about the boost spike other than removing the turbos and porting the wastegate oriface. The boost is spiking to about 12 - 12.5 psi (damn DEFI guage). Is this too much for the stock ECU and fuel system to handle?
Please help!
I have an apex'i N1 dual exhaust but still have the stock cats.
Is there anything I can do about the boost spike other than removing the turbos and porting the wastegate oriface. The boost is spiking to about 12 - 12.5 psi (damn DEFI guage). Is this too much for the stock ECU and fuel system to handle?
Please help!
#2
Banned. I got OWNED!!!
Join Date: Feb 2001
Location: Silicon Valley Bay Area
Posts: 102
Likes: 0
Received 0 Likes
on
0 Posts
Granted that is an accurate display of ur true boost I would say that I never lost an engine to that.
Only when I went into the 15+psi on stock ECU and fuel system was it a problem.
Start saving $$$$ to get ur turbos rebuilt and ported by a company like BNR. That fixed my boost creep along with the PFC.
Only when I went into the 15+psi on stock ECU and fuel system was it a problem.
Start saving $$$$ to get ur turbos rebuilt and ported by a company like BNR. That fixed my boost creep along with the PFC.
#7
Mr. Links
iTrader: (1)
Originally posted by rye_and_7
It's a spike...
It settles back down to about 10 psi after a short time.
It's a spike...
It settles back down to about 10 psi after a short time.
Either manual:
https://www.rx7club.com/forum/showth...hreadid=178136
or a GReddy Profec B will do the trick.
Trending Topics
#9
Junior Member
Thread Starter
Join Date: Aug 2003
Location: Ottawa, Canada
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
I'm not sure if an electronic boost controller will govern a transition spike properly.
Besides, do you guys really think that a transition spike of this size could kill my engine???
Besides, do you guys really think that a transition spike of this size could kill my engine???
#10
Full Member
Join Date: Feb 2002
Location: Wellington - NZ
Posts: 188
Likes: 0
Received 0 Likes
on
0 Posts
Like Mahjik suggested you could go down the manual path that Damian designed ... I've done that and it's awesome, speeds up the transition to boot.
Couldn't find any well priced valves down here so built them instead .. https://www.rx7club.com/forum/showth...hreadid=203040
Couldn't find any well priced valves down here so built them instead .. https://www.rx7club.com/forum/showth...hreadid=203040
#14
Junior Member
Thread Starter
Join Date: Aug 2003
Location: Ottawa, Canada
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Thanks BATMAN.
I am planning on putting in a PFC or AEM (the only good tuner we have here installs AEM!).
I will probably have to port the wastegate at the same time (or sooner).
I was just wondering if there was anything I could do in the meantime...
I read the post you referred me to, lots of good info...
Thanks
BTW, DaiOni, my boost pattern was 10-8-10 and is now 10-8-12-10. The 12 is only for a short period of time however.
Shaun I will look at your thread in a minute... looks interesting.
I am planning on putting in a PFC or AEM (the only good tuner we have here installs AEM!).
I will probably have to port the wastegate at the same time (or sooner).
I was just wondering if there was anything I could do in the meantime...
I read the post you referred me to, lots of good info...
Thanks
BTW, DaiOni, my boost pattern was 10-8-10 and is now 10-8-12-10. The 12 is only for a short period of time however.
Shaun I will look at your thread in a minute... looks interesting.
#15
Banned. I got OWNED!!!
Join Date: Feb 2001
Location: Silicon Valley Bay Area
Posts: 102
Likes: 0
Received 0 Likes
on
0 Posts
If ur 12, u'll be OK for now until the wastegate starts to wear out. Then it starts to climb up a pound or 2.
What u can do with a PFC is tune the boost down to 7PSI and that should compensate for the creep........
What u can do with a PFC is tune the boost down to 7PSI and that should compensate for the creep........
#16
Rotary Enthusiast
iTrader: (2)
Originally posted by rye_and_7
I'm not sure if an electronic boost controller will govern a transition spike properly.
Besides, do you guys really think that a transition spike of this size could kill my engine???
I'm not sure if an electronic boost controller will govern a transition spike properly.
Besides, do you guys really think that a transition spike of this size could kill my engine???
Again, why not reduce the size of the orifice in the prespool line to reduce the amount of prespool prior to transition? You have a classic case of boost spike, not creep.
#17
Junior Member
Thread Starter
Join Date: Aug 2003
Location: Ottawa, Canada
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Thanks John,
I will try that...
Next question is how?
I am not sure which is the prespool line and how I would reduce the oriface (smaller tube?)
Thanks again for all your help!
I will try that...
Next question is how?
I am not sure which is the prespool line and how I would reduce the oriface (smaller tube?)
Thanks again for all your help!
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