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Lend Me Your Expertise - Few Issues

sydking

By sydking,
in Engines & Forced Induction

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sydking Veteran

sydking

Posted
Posted

Gents,

I’ve got a few little issues that im seeking clarification on – Firstly, Rb26, -9s.

So, Car was tuned with the BOV blocked ( Stock 32 GTR BOV’s)

To cut a long yarn short…. They were unblocked yesterday and Vacuum lines plugged in ect

Way home the car felt real doughy, Had to mash the pedal to get the boost ramping up and was revving out to 7k+ with ease… 2nd gear ect, just felt like it needed much more work to get it up and going

As beforehand quarter throttle would see the boost ramp up real quick, couldn’t go over 6k and keep the car straight, First gear used to be non existant as now I can get upto 5k ish – Its behaving much more like a NA

EBC is still getting the boost to the set 16 PSI – Just feels it’s coming on much later in the rev range.

BOV’s have been blocked back up – I.e. were the plastic caps were in place are now wooden chock and clamp - So there is nothing that’s changed in that respect

Car still feels the same ( ie doughy)…… Sound wise…. I can hear the BOV’s venting….. but backing off on boost it doesn't sound like it used to. am I correct in saying with blocked BOV’s I should not be hearing them vent…..

The only other thing that was changed was blocking the oil catch can and venting it back into intake… That should not effect anything.

Im thinking actuators are craking open to early and need to be wound up.

More then happy for someone to come take her for a drive as its hard to explain…. and maybe Ive just lost my mind.... But it sure feels different.

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GTScotT Grand Master

GTScotT

Posted
Posted

So let me just confirm a before and after here..

You had:

Rubber caps on bovs and no vacc lines connected.

Catch catch vented to atmo

Now have:

Wood chocking bovs????????? Vacc lines still connected

Catch can now vent to intake (like stock)

For starters you haven't returned it back to how it was. Secondly, the breathers being connected to intake changes your effective RON and your tune will now be out. The oil mist into the intake stream makes a big difference.

Please clarify the above before we speculate too much.

sydking Veteran

sydking

Posted
  • Author
Posted

Catch can was blocked with bottle caps yes. In place are now solid wooden blocks to fit the hole.

Catch can is a long horror story.... Basically was no return to sump... and no breather attached.... Was basically picking up oil and dumping is straight out of the bottom hole onto the ground... We couldn't block that off as is was causing Crank case pressure

So now the head drain to catch can is blocked off, So essentially the head drains back down like stock. and yes it is breathing back into the intake...

sydking Veteran

sydking

Posted
  • Author
Posted

is the PCV valve still in place and working ?

Will double check on that one... I think ive confused people with the catch can situation, It has to be a BOV issue.... Don't get me wrong.. Car still has its power.. just much later then what it was.

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