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 Forums > Porsche Forums > 911 / 930 Turbo & Super Charging Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered User
 
Join Date: Jul 2006
Location: Burton on Trent UK
Posts: 65
Question 1 bar wastegate spring or not??

I have searched this forum but as I am based in the UK I thought it worth asking.

I have rebuilt the engine, turbo and gearbox on my 85 930 and I am wondering if it is worthwhile me fitting a 1 bar wastegate spring.

How much extra BHP can I hope to get?

How much risk do I have of engine problems?

It is a ROW car and I run it on 97 octane fuel.

The car is used on the road and not on the track.

I think that the CIS will cope with the extra air the 1 bar boost will generate and automatically compensate in terms of extra fuel so I believe that I shouldn't have any problems.

Any advice or views would be welcome.

Many thanks

Steve
Old 05-18-2008, 08:52 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered User
 
Join Date: Dec 2007
Location: London, UK
Posts: 6
Surprised no answers here.
Maybe try on rennlist, lots of 930's running 1 bar there.
Old 05-25-2008, 08:55 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered User
 
Cowtown10's Avatar
 
Join Date: Nov 2007
Location: Calgary AB
Posts: 242
I am running a 1 bar in my 84 930.
I asked the same question on this forum and received lots of mixed feedback.

I have since talked to 2 reputable local shops a very well known shop in California and one in Kansas all have the same professional opinion that is "good to go".
Make sure the diaphram is in good shape
__________________
Q
2002 996TT
1984 930 Turbo (gone and missed)
Old 05-25-2008, 09:05 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
wcc wcc is offline
Registered User
 
wcc's Avatar
 
Join Date: Aug 2005
Location: Michigan
Posts: 3,334
You need to upgrade your intercooler first.
__________________
Bill
Old 05-25-2008, 10:29 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Registered User
 
Join Date: Jul 2003
Location: Glorious Pac NW
Posts: 2,840
Don't bother changing the spring. You can achieve the same result with a manual boost controller that costs about $50, without having to dismantle the wastegate or buy a spring. You can also change the boost level back down (e.g. on hot days) without needing to dismantle the wastegate.

An MBC can also prevent premature wastegate opening at low boost levels - e.g. before the "correct" setting - because the wastegate doesn't "see" any boost until the MBC opens and lets it through.

I was told that each .1 bar is worth about 12-20 HP, but also that there are better ways to get the same power with less stress on the motor - e.g. a better turbo and intercooler is worth about 100HP at factory boost level, but intake charge temperatures will be lower, due to better cooling (intercooler) and less heat imparted (better compressor maps).

You might want to bear in mind that US readers are used to octane ratings calculated as (MON+RON)/2, sometimes known as the "Road Octane Number". Don't confuse this with the RON used in the formula above, this is the "Research Octane Number" - which UK filling stations post on the pump.

With a 930, you should pretty much always use the highest-octane rating you can buy. Especially if you're going to increase the effective compression ratio by increasing boost. This was well illustrated by the most useful graph someone (else) posted here recently:

__________________
'77 S with '78 930 power and a few other things.
Old 05-25-2008, 03:26 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
A fellow Pelacanite
 
NathanUK's Avatar
 
Join Date: Nov 2006
Location: UK
Posts: 2,002
Garage
To run 1bar you need to either change your turbo for a K27 variety or upgrade the intercooler. Ideally you should do both...

You also need to check your AFR's at WOT, not just idle...
__________________
1981 UK 930. G50/01 shortened, 964 3.8RS Fibreglass Body Kit, 18" Alloys 8.5" F & 10" R, 225's F & 285's R, Special Colour Metallic Blue Paint, FIA Sparco Evo's, A/C and Air Pump removed, Electronic Boost Controller, GHL Headers, Tial46 WG.
Fitting - New service kit.
Needs Fitting - Innovate XD-16 Kit, Kokeln IC. Stephen's K27 HFS, EVO Intake Assy & his Modded USA Fuel Head.

1983 UK 911 3.2 Carrera Sport Coupe. Black, Black Leather with Red Piping, Black Alloy Gear Knob, K&N Air Filter Element, Turbo Tie rods.
Needs Fitting - K&N CO Sensor, Round A/F Dial Gauge, Factory Short Shift Kit.

http://www.danasoft.com/sig/Iamnotanumber.jpg
Old 05-27-2008, 03:03 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #6 (permalink)
Registered User
 
Join Date: Jul 2003
Location: Back in B'ham, AL
Posts: 3,416
No 1bar spring.

.8 is good and safe enough.
Old 05-29-2008, 01:21 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #7 (permalink)
Crotchety Old Bastard
 
RarlyL8's Avatar
 
Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,563
Garage
Of course a shop will tell you 1bar is good to go. They'll also sell you the springs and rebuild your engine after it dies an early death.

Talk to the folks who have run 1bar for many years without issue and see what they did to make it safe.
__________________
RarlyL8 Motorsports / M&K Exhaust - 911/930 Exhaust Systems, Turbos, TiAL, CIS Mods/Rebuilds
'78 911SC Widebody, 930 engine, 915 Tranny, K27, SC Cams, RL8 Headers & GT3 Muffler. 350whp @ 0.75bar
Brian B. (256)536-9977 Service@MKExhaust Brian@RarlyL8
Old 05-29-2008, 08:48 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #8 (permalink)
Reply

Thread Tools
Rate This Thread
Rate This Thread:

 


All times are GMT -8. The time now is 05:35 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.