I recently did some engine upgrades on my 03 XJR:
1.) Lower Crankshaft Pulley
2.) Ported Supercharger w/ 2.5 to 3.0 pulley
3.) Low Temp Thermostat
4.) Arden Supercharger Intercooler
5.) Johnson supercharger coolant pump
6.) Spark plugs
7.) 60K Transmission service

Before: Max POWER: 339.4 After: Max POWER: 351.0
Before: Max TORQUE: 316. After: Max TORQUE: 359.1

The car is lightning quick I MEAN LIGHTNING QUICK!

I only had the car back from the shop for about 20 miles before the check engine light came on (Color: Yellow). I will take it back tomorrow to have the codes read. One thing I that didn't have done was the ECU remapped but Eurotoys LTD said that after doing test that I didn't need it. eurotek offers it. The shop I went to didn't have the software . They probably can send it off to have it remapped. Does anyone have any idea what the issue might be? I will give you an update tomorrow with my findings.

 

my wild guess, 02 Sensor.....

 

The code was PO171. The OBDII said that Bank 1 was running lean. The tech checked all vacuum hoses and reset the code. He said if the check engine light comes on again he will do a smoke check on it to find the leaks.

 

May I ask how much the upgrades cost? They sound really impressive!

 

The lower crankshaft pulley cost $420 thru Phoenix Coachworks UK. The Roots M112 supercharger was bought thru Ebay $300. The 2.5/3.0 psi upper pulley and low temp thermostat was purchased through Eurotoys Ltd amount $283. The supercharger and upper pulley were sent to PSE Superchargers for machining & porting. The supercharger intercooler radiator was purchased through Eurotek Designs amount $1395. The Johnson CM32 pump was purchased through Buckhead Imports $175 at the time of install. Buckhead Imports in Atlanta GA did the install. A very professional group of people. The total install cost me $1775 including gaskets and seals for supercharger. I also included spark plugs and a 60k transmission service which was another $700. I also have a Borla full cat back exhaust system with a direct air charger. The car is night and day. Extremely quick! I am willing to guess that it will cover the 1/4 mile in the low 12's. Mid range in this car is Simply Devastating! From 50 to 70mph is where you really see all the improvements. You are really in the meat of the power band. I am willing to say this is a stop light drag king car. Look out for Dyno info on youtube within the next couple of days. You need to do these upgrades for real!

 

You might want to check out Eurotek. They're in New York. Here is their site. With the upgrades you got, I would say and ECU remap is needed according to what their site says. Let us know what they say.

http://www.eurotekdesigns.com/main.html

 

What is Eurotek's phone number? They do not have one on there site and no contact us info.

 

I went to the web site to check things out and I saw the phone number is at the bottom of their main web page, you just have to scroll down to the bottom and it's there

 

I believe I've finally solved the Check Engine light dilemma. I took my XJR to Buckhead Imports and they did a thorough check of the electrical system. They concluded that my battery was causing my engine to misfire which in turn gave a P0300 code. The battery had some dead cells. They did change out the crank position sensor, followed the wiring from battery to the alternator. There were no damage wires or melted grommets. The electrical flow from the battery was inconsistent.

 

No way that xjr gets into the low 12's with that minimal upgrade in hp. Matt Moran had a 80hp boost and his was mid 12's. Mercedes E63 does mid 12 with 507 hp