Right the 2003-2005 was rated 390hp, the 2006-2009 was rated 400hp.

The major change there was VVT added on the 2006-onward engines, which does make a difference, especially when you try to squeeze more power out with a tune.

 

Thanks! Next question...If I have my old pulley cut off with an air whizzer can I press the new pulley on with a washer and grade 8 bolt? Or am I better off renting the puller installer tool?

 

I have read in this forum where some people have had success in heating up the pulley and then pressing it on "fairly" easily.

I still have my original SC which is in great shape so might well try this method
when I get around to installing the 1.5 pulley.

I actually have a Eurotoys 2.6 pulley on right now not a 3lb pulley.

On their website Eurotoys advertise a 2.5 lb pulley and not a 2.6. So maybe my invoice from PSE is incorrect?

 

I was eyeing off the Eurotoys 2.5lb pulley for my 2006 XJR. Still haven't decided whether the 1.5 or 2.5 would be best, I don't drag or race, just road use only.
I have 200cell cats, Xpipe, resonators removed & charge pipe.

Is the 2.5lb going to provide much more power over the 1.5lb?

 

no is the short answer .
1.5# seems to work best on and off road . according to what i have read .

 

Stupid question, why would a STR be quicker? I understand the wheel issue (easily fixed), but the X350 is lighter than a STR? When I have raced STRs, I only lost to one by a small amount due to it having NOS.

 

The 20" wheels really blunt the acceleration. Not only that the rolling circumference of the STR wheel/tyre combo is smaller than that of the XJR, regardless of rim size.

 

If you also look at the best times between X350 XJRs and STRs, the best times seem to have come from STRs although trap speeds are similar. That's likely due to the shorter gearing of the STR getting it off the line faster as Cambo says, but we've also got wider tyres standard. There has been a few STRs on this and the UK forum running high 12s without TS/NOS for a long time, whereas Cambo is the first X350 XJR to do that because of the tune. I bet if the tune was applied to 1320racers car which currently has the fastest time of either model, we'd see 12.8 at 110mph+ based on the data I've seen from the tune.

 

Is an STR heavier than an XJR??? Looks lighter to me...

 

The STR on paper according to all the specks I've read is 10kgs heavier than the x350 XJR . At 1800kgs STR and 1790kgs XJR both unladen weights , I'm guessing dry weights .

There is not much in it really !

 

My XJR weighed in at 1760kg with the spare & jack removed, 1/4 tank of fuel, no driver.

Any weight advantage is lost when you put a fat ******* (i.e. me) behind the wheel.

 

ha , priceless!
I'm the other end of the scales then ,
i hardly press the occupancy sensor .

it does look to be wet weights then .

 

I still have the Mina pulley in the box. I'm not sure if I want to do the job myself or take it in to the shop. The puller I have does not fit over the stock pulley.