VS sc V6 unstable idle issue

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vHell83
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Re: VS sc V6 unstable idle issue

Post by vHell83 »

0081 wrote:The stock throttle body has 2 connections one before the one after the blade.
As the LS throttle only has one most people drill and tap the ubend on the flange where the throttle body bolts to or if you have an adaptor on the stock ubend you can drill and tap that
Do you have an image of such being done?

Cheers
vHell83
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Re: VS sc V6 unstable idle issue

Post by vHell83 »

vlad01 wrote:where does the PCV inlet connection go now that there is no connection on the TB?
Eco TB has 2, one goes to the canister the other to the PCV.

LS has one large 1 for the PCV only.
0081
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Re: VS sc V6 unstable idle issue

Post by 0081 »

vHell83 wrote:
0081 wrote:The stock throttle body has 2 connections one before the one after the blade.
As the LS throttle only has one most people drill and tap the ubend on the flange where the throttle body bolts to or if you have an adaptor on the stock ubend you can drill and tap that
Do you have an image of such being done?

Cheers
Which one the larger ubend drilled or into an adaptor bolted to a stock ubend?
VX L67 Getrag
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Re: VS sc V6 unstable idle issue

Post by VX L67 Getrag »

The best source of vacuum for any main things like fuel pressure reg & map if fitted for any of the players out there is the lower intake manifold!
MAGP
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Re: VS sc V6 unstable idle issue

Post by MAGP »

VX L67 Getrag wrote:The best source of vacuum for any main things like fuel pressure reg & map if fitted for any of the players out there is the lower intake manifold!
Shouldn't that be "the best source of manifold pressure (+ or -) is ...."
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Re: VS sc V6 unstable idle issue

Post by vlad01 »

MAGP wrote:
VX L67 Getrag wrote:The best source of vacuum for any main things like fuel pressure reg & map if fitted for any of the players out there is the lower intake manifold!
Shouldn't that be "the best source of manifold pressure (+ or -) is ...."

yes thats correct, critical for a MAP based L67 and for the fuel reg, not ideal for the brake booster or PCV, though they still work as they have both check valves but there is room for failures, faulty valves or blowing off hoses. Also for the PCV and booster there is more time in vac conditions and stronger vac when connected to the elbow between TB and SC inlet and even in part throttle there is good vac, while the LIM is actually under some boost.

So sum it up, at idle there should be no difference between the 2 (unless the bypass fails) , but part throttle the elbow wins hands down for vac. Thats why the factory has the booster and other vac operated connected there except the fuel reg.
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vHell83
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Re: VS sc V6 unstable idle issue

Post by vHell83 »

0081 wrote:
vHell83 wrote:
0081 wrote:The stock throttle body has 2 connections one before the one after the blade.
As the LS throttle only has one most people drill and tap the ubend on the flange where the throttle body bolts to or if you have an adaptor on the stock ubend you can drill and tap that
Do you have an image of such being done?

Cheers
Which one the larger ubend drilled or into an adaptor bolted to a stock ubend?

The u bend being drilled.
vHell83
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Re: VS sc V6 unstable idle issue

Post by vHell83 »

vlad01 wrote:
MAGP wrote:
VX L67 Getrag wrote:The best source of vacuum for any main things like fuel pressure reg & map if fitted for any of the players out there is the lower intake manifold!
Shouldn't that be "the best source of manifold pressure (+ or -) is ...."

yes thats correct, critical for a MAP based L67 and for the fuel reg, not ideal for the brake booster or PCV, though they still work as they have both check valves but there is room for failures, faulty valves or blowing off hoses. Also for the PCV and booster there is more time in vac conditions and stronger vac when connected to the elbow between TB and SC inlet and even in part throttle there is good vac, while the LIM is actually under some boost.

So sum it up, at idle there should be no difference between the 2 (unless the bypass fails) , but part throttle the elbow wins hands down for vac. Thats why the factory has the booster and other vac operated connected there except the fuel reg.

My vacuum setup was all joined up into one with t pieces. So map (when it was running) boost gauge etc all coming off the front of the manifold. While pcv had its own and boost tree not in use.
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Re: VS sc V6 unstable idle issue

Post by VX L67 Getrag »

Yeah pcv is built in under plate of charger & the brake booster runs off the back of charger u bend before throttle along with the heater vac hose!

But yeah my bad lim is positive & negative pressure (not just vacuum) thanks for clarifying that!
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Re: VS sc V6 unstable idle issue

Post by 0081 »

vHell83 wrote:
The u bend being drilled.
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