I named the thread supercharger repair but it's more. My car has developed the dreaded heater hose leak under the blower. Of course the blower needs to be removed and replaced ($2000) to replace the hose. So while the blower is separated from the engine, I's going to have it rebuilt, ported, and a smaller pulley installed. The blower work by Stiegemeier. Now for the question: What would be the consequences of enlarging the fuel injectors? Would the ECU need to be remapped? Would any other problems crop up that I should know about before the surgery? Thanks for any advice.

 

Mr. Weber,


First of all...Do you plan to Port the Engine someday soon? If not, you sure don't need to spend your Money Porting the S/C and No you don't need to change the Injectors.....They are Big enough to power your XKR...and with only the small Pulley change, you don't need the ECU Tuned......Also, $2,000.00 to change the Heater Hoses is a bit much......


Sounds like someone has gotten in your "Ear" and is working their way to your "Pocket Book"!!!!! I don't know who Stiegemeier is but they are guessing! There are better and cheaper ways to get this job done.....


By the way, what kind of a Car is it? I want to guess an XKR but you didn't say? Is there something wrong with the Blower?


Billy Clyde in Houston

 

Short version is that for a normal/mild pulley upgrade, the existing programming should supply more fuel out of the stock injectors.

With the smaller pulley on the charger (and/or a larger pulley on the crank), you are going to be able to move more air. That air will be measured by the air flow meter, and the ECU will therefore increase the duty cycle of the injectors to provide the matching fuel. This will hold true for as long as the injector duty cycle remains below a cap (of, say, 80%). The fuel pressure has to be monitored as well to make sure it remains at the normal 55psi, and does not drop off. One would think that if you buy this pulley from a known tuner, these tests would already have been done as part of the design. This scenario covers a large majority of street/mild upgrades, I believe.

As far as supercharger maintenance, you might want to do some research. Folks talk about replacing needle bearings, as well as restoring internal coating to minimize secondary flows. FWIW, I believe pulleys can be done at any time, with the supercharger in place.

 

Stiegemeier Porting Service is one of the best supercharger rebuilders in the US. The consensus of thought is that no ECU tuning will be necessary for the up-sized injectors.
Thanks.
Billy, $2000 for a repair of that hose is pretty standard, wait till you go looking!

 

Rich,


I don't doubt Stiegemeier is a good S/C rebuilder, I know they are! That's not where I'm coming from.....The question is why you would need to Port and rebuild your S/C? Is something wrong with it? Your Information finally showed a Photo of your (2) Cars and now I know we're talking about an 2004 XKR. Unless there is something wrong with it, like the Bearings are completely gone, about all that S/C could need would be to change the Oil......If you are trying to make more HP, Porting it is not the way to go! The small pulley will not help a great deal either as it is only a part of the deal.


I've done this trick to all 3 XKR's I've owned, including the one I currently own and drive. If you want to gain 45 to 60 HP and a whole bunch of Torque, let me know and I will tell you how! Also, you will need about $3,000. to get the job done right, maybe $3,500. now! I know this works as I have the proof in the Driveway...........


Billy Clyde in Houston

 

Ok, I'll bite, what did you do?
Rich.

 

How about posting your dyno runs. Before and after.

Btw no one of repute, except for Cambo, can do an ECU tune on a pre 2006 MY Jaguar.

 

rweber. I think you have the same engine that I have the 4.2 SC.

One thing you should do with the SC off is clean the charge coolers as they are likely to be carboned up with soft carbon deposits reducing their effectiveness drastically.

I did that and fitted an oil catch can to help reduce carbon build up.

I also installed a meth/water injection system for exactly the same reason as well as reduce heat soak on hard acceleration.

I did port my SC but in retrospect I believe that was a waste of time however no harm done at least just wasted money.

Also installed the smaller pulley and again in retrospect I should have gone with the larger pulley but still smaller than original.

I made my own stage 1 cool air intake.

I upgraded the SC pump and installed an additional SC radiator in series with the original along with twin 6" fans.

Installed 200 cel cats.

I also installed a Quaiffe LSD which is truly the best mod I have made.

I also installed a X-pipe in place of the front resonator.

If I had the money I would have installed a more powerful and later design super charger that was offered as a kit in this forum. That would have cost about $6k I think a while ago.

On the X350 at least the electronics were changed fairly substantially in the 2006 model year and reputable ECU tuners no longer cater for pre 2006 X350 model years.

The only reputable person that may is Cambo in this forum and even he says the gains for my car at least are minimal.

I am not aware what else can be done other than reducing weight.

Your car is I believe about 150 lbs lighter than mine.

 

How about the dyno print outs Billy Clyde?

"proof in the Driveway................" hardly definitive.

Just my opinion.