Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Technical BBS > 1- Porsche Technical Forums > 911 / 930 Turbo & Super Charging Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered User
 
Join Date: Aug 2006
Posts: 4
Garage
Engine cut off

Under hard acceleartion at around 6-6,500 rpm and just before the rev limiter cuts in the engine cuts out and the electrics go dead. Give it a second or two, switch it off and back on and it goes fine. Has anyone any suggestions please what might be worth checking? It first started happening on a track day but it could be because I'm now driving a lot harder as I get used to the car.

It's an '84 930 with K27, sc cams., 1 bar boost spring, Haywood and Scott twin exhaust (similar to B&B headers I guess) and Zucz powerflow airbox.

Any help gratefully received guys.
Old 03-25-2007, 11:09 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered User
 
ChrisBennet's Avatar
 
Join Date: Aug 2001
Location: Nashua, NH USA
Posts: 8,072
The overboost switch?
-Chris
__________________
'80 911 Nogaro blue Phoenix!
'07 BMW 328i Coupe
http://members.rennlist.org/messinwith911s/
Old 03-26-2007, 03:31 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered User
 
9dreizig's Avatar
 
Join Date: Jul 2005
Location: Reno NV, Bay Area during most weeks,, Kids still in NH
Posts: 5,738
Send a message via AIM to 9dreizig
Chris,
Glad to see you frequenting this forum ( bet you feel like you own one huh? LOL)
__________________
"Todd"
98 Tahoe ,2007 Saturn Vue
86 930 black and stock, 80 930 blue tracdog
91 Spec Miata (yeah I race a chick car)
"life"ll kill ya" Warren Zevon
Old 03-26-2007, 08:42 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Registered User
 
Join Date: Aug 2006
Posts: 4
Garage
Hi Chris

Thanks for your reply. I had that replaced last week, took it out for a drive this weekend and the same thing happened. What I can't undertand is why the elctrics go dead but it then restarts without any problems. Not really sure whether there are any other relays worth considering?
Old 03-26-2007, 12:47 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Registered User
 
9dreizig's Avatar
 
Join Date: Jul 2005
Location: Reno NV, Bay Area during most weeks,, Kids still in NH
Posts: 5,738
Send a message via AIM to 9dreizig
Maybe a heat issue with the CDI box?? I didn't think there was a rev limiter on an 84 turbo??
__________________
"Todd"
98 Tahoe ,2007 Saturn Vue
86 930 black and stock, 80 930 blue tracdog
91 Spec Miata (yeah I race a chick car)
"life"ll kill ya" Warren Zevon
Old 03-26-2007, 12:53 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
Registered User
 
ChrisBennet's Avatar
 
Join Date: Aug 2001
Location: Nashua, NH USA
Posts: 8,072
Quote:
Originally posted by jono450
Hi Chris

Thanks for your reply. I had that replaced last week, took it out for a drive this weekend and the same thing happened. What I can't undertand is why the elctrics go dead but it then restarts without any problems. Not really sure whether there are any other relays worth considering?
Stock boost is something like .8bar isn't it?
The stock overboost switch opens when it detects more then stock boost. I'm just picking a number out of the air but lets say it trips at 1.1bar. You've increased your boost by virtue of your 1 bar spring so now you are much closer to an overboost condition. Under boost you will experience short periods of boost greater than 1 bar even though your 1 bar spring "limits" boost to 1 bar.

A friend with a '91 911 Turbo when through this and ended up removing the 1 bar spring.

-Chris
__________________
'80 911 Nogaro blue Phoenix!
'07 BMW 328i Coupe
http://members.rennlist.org/messinwith911s/
Old 03-26-2007, 12:56 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #6 (permalink)
Registered User
 
9dreizig's Avatar
 
Join Date: Jul 2005
Location: Reno NV, Bay Area during most weeks,, Kids still in NH
Posts: 5,738
Send a message via AIM to 9dreizig
Chris I believe that the std overboost switch limits it to 1.3 bar if I"m not mistaken
__________________
"Todd"
98 Tahoe ,2007 Saturn Vue
86 930 black and stock, 80 930 blue tracdog
91 Spec Miata (yeah I race a chick car)
"life"ll kill ya" Warren Zevon
Old 03-26-2007, 01:01 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #7 (permalink)
Registered User
 
ChrisBennet's Avatar
 
Join Date: Aug 2001
Location: Nashua, NH USA
Posts: 8,072
Re: Engine cut off

Quote:
Originally posted by jono450
Under hard acceleartion at around 6-6,500 rpm and just before the rev limiter cuts in the engine cuts out and the electrics go dead. Give it a second or two, switch it off and back on and it goes fine. Has anyone any suggestions please what might be worth checking? It first started happening on a track day but it could be because I'm now driving a lot harder as I get used to the car.

It's an '84 930 with K27, sc cams., 1 bar boost spring, Haywood and Scott twin exhaust (similar to B&B headers I guess) and Zucz powerflow airbox.

Any help gratefully received guys.
What do you mean exactly by "the electrics go dead"?
Do your headlights go out?
Do the gauges go dead?
Or do you mean the ignition cuts out?
-Chris
__________________
'80 911 Nogaro blue Phoenix!
'07 BMW 328i Coupe
http://members.rennlist.org/messinwith911s/
Old 03-26-2007, 01:12 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #8 (permalink)
Registered User
 
Join Date: Aug 2006
Posts: 4
Garage
Can't say for definite but from what I recall there's no ignition lights until I've turned it off and on again but the dials are still working. I'll need to check the next time I'm out which won't be for another couple of weeks because I'm off on vacation. I'll post back when I've been for another drive and found out for sure.

Thanks for the the replies so far.
Old 03-27-2007, 11:35 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #9 (permalink)
Gotta Jibboo
 
BSiple's Avatar
 
Join Date: Feb 2002
Location: Fort Collins Colorado
Posts: 4,952
Garage
Send a message via AIM to BSiple
Having just dealt with the overboost issue, I have heard anywhere from 1.3-1.4 bar boost is what kicks in the switch.

As there isn't much to go wrong with the switch, and its pretty easy to replace.

Bill
__________________
2003 996TT
1992 964 Turbo (sold) Holy crap are these expensive now!
1986 911 Cabriolet (sold)

I don't know why I do the hillbilly things I do.
Old 03-27-2007, 02:27 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #10 (permalink)
Registered User
 
9dreizig's Avatar
 
Join Date: Jul 2005
Location: Reno NV, Bay Area during most weeks,, Kids still in NH
Posts: 5,738
Send a message via AIM to 9dreizig
I don't want to hijack this thread but my buddy who is driving my car out west for me tells me that mine is cutting out at around .9 bar on the boost guage ( and I only have a 0.8 bar spring in it). I do have a k27-7200 turbo in it. When he eases off the throttle to a milder boost it runs fine. Any suggestions?
__________________
"Todd"
98 Tahoe ,2007 Saturn Vue
86 930 black and stock, 80 930 blue tracdog
91 Spec Miata (yeah I race a chick car)
"life"ll kill ya" Warren Zevon
Old 03-27-2007, 02:52 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #11 (permalink)
Gotta Jibboo
 
BSiple's Avatar
 
Join Date: Feb 2002
Location: Fort Collins Colorado
Posts: 4,952
Garage
Send a message via AIM to BSiple
The first thing I would check is to make sure the WG is functioning properly. If it is, then go to Rennlist, and do a search for 'overboosting" in the 964 turbo forum. One of the members moved his overboost switch to a line off the intake to elimate boost spiking, and it cured his problem.

Bill
__________________
2003 996TT
1992 964 Turbo (sold) Holy crap are these expensive now!
1986 911 Cabriolet (sold)

I don't know why I do the hillbilly things I do.
Old 03-27-2007, 02:53 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #12 (permalink)
Reply

Thread Tools
Rate This Thread
Rate This Thread:

 


All times are GMT -8. The time now is 03:33 PM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.