I am having a hard time getting my XJR performing like I heard and see everybody elses.

Per my watch timing, I getting about 7 sec 0-60, I have already changed the spark plugs, air filter, oil change, cleaned the driver side part thingy, and new fuel filter. All in all this has improved my time to 7 sec, but I do not hear the so call "WHINE" from the SC.

The engine roars when it goes into kickdown and that only happened when I adjusted the throttle cable.

Is getting to the bypass as hard as I hear, have to remove the entire supercharger? Is their a way to test it before I get to all of that? Can I reach some where and see if the valve move?

Thanks in advance.

SGB

 

the bypass is semi assessable if you remove the TB but to get it off the inlet has to be removed from the supercharger completely. The supercharger itself does not have to come off. I cleaned mine up nicely when it was off and did notice tht if you loosen up the bypass valve and pull it back it will tighten up the valve a lil not much but enough to hold it closed better.

 

Today while trying to locate the rattle, I had the rear tire off the ground (on jack stands). Popped the hood, started the car, turn off traction control and press the gas pedal, I hear the whine but it semi low, but I hear more of a roar, no bearing noise, just a nice clean roar.

So I am guessing my bypass valve it stuck open, the weekend I will remove the TB and see if I can pull of the plunger to close it some.

Thanks.
SGB

 

dont be so quick I even removed both silencer tubes on the stock intake and blocked em off and still couldnt hear it not til I did my new intake could I hear the blower scream

 

Removing the hood insulation made the supercharger more audible, although it could be heard above 5000rpm quite clearly before that too. Looking forward to hearing the difference with the lower pulley from Powerhouse

 

The insulation is not the problem, because I had the hood up. I was watching a youtude video yesterday and the SC is clearly heard, even with the windows closed.

I want to hear my too

 

Did you get to the bypass valve yet? Did it solve the performance issue?

My XJR was on the dyno a few days ago, and got only ~280rwhp, it may have the same problem...

EDIT: sorry, just found the other thread with the solution

https://www.jaguarforums.com/forum/x...-fixing-74803/

 

Its not a problem, that probably where mine was too.

That clogged ERG port was my issue, it is very easy to remove the TB, once you remove it look down into the mount on the engine and you will be able to see it.

I going to create a write up tonight when I get home. All XJ owners should check or have it check to see if it theirs are clogged.

ALSO, did you do the cable adjustment?