[s-cars] 1.9 Bar Wastegate Spring

[Mark Strangways]

It's amazing how inaccurate the butt dyno actually is.
I think most people will perceive spiky torque curves as more power. That is 
not usually the case.
I was not really commenting on the 1.9 BAR spring, just the effects of 
adjusting the WG spring.

A higher spring rate will solve some WG creep issues as will cranking the 
spring seat down.
The ECU software should be optimized to play well with an adjusted WG 
spring, otherwise the two can tend to fight each other. The WGFV may try to 
lower the boost pressure too soon due to the spike caused by the spring 
being screwed in to much. Then since again the spring is tight, it will slam 
the WG closed faster causing this spike again... over and over.

YMMV, just my insight on it.

Mark
----- Original Message ----- 
From: "Dave Forgie" <forgied at ae.ca>
To: <s-car-list at audifans.com>; "Mark Strangways" <StrangConst at rogers.com>
Sent: Wednesday, December 27, 2006 11:23 AM
Subject: Re: [s-cars] 1.9 Bar Wastegate Spring


> Mark:  I can't disagree about the WGFV and ECU's roll in controlling
> boost levels.  However, I can say that I do like the 1.9 bar WG spring.
> It provides a lot crisper initial throttle response and, I think, more
> rapid boost rise. (Max is still limited by the ECU and WGFV).
>
> You might remember that I posted about our Vancouver club's DynoDay
> last March.  I ran the 1.9 bar spring on my first set of runs but there
> was a lot of spiking in the HP and torque.  Later in the day, I put the
> car back on the dyno with the stock spring - it made more horsepower.
> However, within a week, I put the 1.9 bar spring back in. It just felt
> better.  Mind you, this time I turned the adjustment screw all the way
> to the top (instead of 3 to 6 threads in with the stock spring). Worked
> a treat.
>
> The spiking problem is gone and being RS2'd throughout all this, the
> car pulls like a freight train.  I will not go back to the stock spring
> again. Ever.
>
> YMMV
>
> Dave F.
>
>>>> "Mark Strangways" <StrangConst at rogers.com> 12/27/06 07:39AM >>>
> I suppose my (drunken) point was, it's not the way to increase your
> boost.
> Let the WGFV and software do that.
> There are reasons to adjust it, but they are not to increase your
> boost.
> I have had to adjust mine when using TAP stage 3 software, otherwise it
>
> would overboost and cause the ECU to throw error codes. They the boost
> was
> in limp home mode which is no fun.
>
> I know what adjusting the WG spring can do, I just feel that the job of
>
> boost control should be left to the ECU and WGFV.
>
> Mark
> ----- Original Message ----- 
> From: "gsfent" <gsfent at bellsouth.net>
> To: "Mark Strangways" <StrangConst at rogers.com>;
> <s-car-list at audifans.com>
> Cc: <forgied at ae.ca>
> Sent: Tuesday, December 26, 2006 11:21 PM
> Subject: Re: [s-cars] 1.9 Bar Wastegate Spring
>
>
>> Mark
>> I have been running a shimmed WG spring for years. I pull max of
> 20psi on
>> my VDO. I do have an IA stage 3 chip, and a k24/26 turbo from 2B. Car
> has
>> over 200k miles and pulls like a freight train. When I hit 22 or 23
> psi, I
>> get the fuel shutoff, so 20 is max on my setup.
>> Regards,
>> Jerry
>> '91 200tqa
>>
>
>