Hello,

I have a xj8 2002 Vanden Plas edition with a healthy engine. I wanted to know what I can do to increase its power . Second question is what is the maximum tire width I can put .

Input would be appreciated, Thank you

 

The only really practical upgrade would be to buy a XJR. Engine swap would be expensive.

 

To echo above, there's almost nothing out there for these as far as just bolt out power. It's not a small block chevy. And it's even more sparse with the N/A engine. Intake and exhaust are about all there are, and the gains will be minimal. As far the tires, I find the 255's just fine, but you MIGHT get a little wider before rubbing's an issue, unless you're prepared to roll your fenders. I know there are some meaty rollers on a couple cars on here.

 

It depends on how far you want to go, if you had a spare $50K then you can do this

 

I saw where you originally posted in the wrong forum, and noted that you already had an air intake. Can you post a pic? I couldn't find an aftermarket one for mine so I customized the factory one.

Leaks are common in these intake tubes so sealing them up helps restore power. There could easily be leaks that go unknown of. If you have a complete aftermarket setup, that should solve this.

If you were going to spend any real money on a real power adder, I would suggest one or more turbos. There is plenty of room.

BTW, welcome and hello.

 

I believe he said in another thread that he just got this car. Perhaps he chose VDP for a reason that the supercharged model did not offer. I would rather have the VDP than the XJR, but that preference is based on passenger needs instead of performance.

 

Why do people want more power out of an XJ8.
IF YOU WANT MORE POWER BUY AN XJR!!!!


If you want the best performance from your XJ8 do all of your maintenance.

I recently did the secondary tennsioners along with new plugs and cam cover gaskets. There was a noticeable increase in power.

 

Why give the guy a hard time? He just bought the car. Maybe he wanted the Vanden Plas for whatever reason or maybe that is just whatever car he could get.

 

A can of BG44K restored power on my XJ8 a very noticeable increase. @Fast71SS do you know that there is a VDP supercharged combining the VDP and the XJR.

 

I know that now. That's really cool. I have seen VDP's in my comparison of next-to-nothing value Jags, but no supercharged (standard or VDP). If I could have my pick of any, it would be VDP because of the rear passenger leg room which makes children in car-seats much easier. I had to slide my seat up so far to accommodate them in my XJ8 that my knees opened the boot and turned on the uniwiper.

 

Would love to own a VDP SC.

 

They were also available as Daimler Super V8's in some parts of the world

 

If I sounded mean I apologize. Not my intent.
To convert XJ8 to a supercharged car you will need a replacement engine, a replacement transmission, an ECM and TCM for a supercharged car. There may be other things you need to exchange plus programming the new modules.

IMHO you be cheaper to find an XJR if you want the performance. I believe the suspension and brakes are superior on the XJR. If you want a supercharged VDP I think it would be more cost effective to put a VDP interior in an XJR if you cant find a SC VDP.

 

The new guy just wants more power from his VDP and I believe he is looking for bolt on performance.

I need a replacement jag, want a natural AJ16 in an X300, and would love the rear seat space of a VDP for the children.

Nobody is looking to add a supercharger.

 

I appreciate all the input. If I could afford the XJR I would have gone for that but I had to settle for what I could get at the time. Jaguars have always been a dream for me to get and now that I have one I want to make sure it's mint along with some power. I have changed the valve cover gaskit and plugs as well as a new air filter.

Thanks for all the help I will keep It as is for now since after all it isn't a racing car it's more for a long comfortable cruise.

If i have more questions about engine swaps etc I will get back to you guys!

 

Hammad, welcome to the forum

 

Welcome Hammad,

Just do the suggested maintenance, use the proper products, you will have a quality machine that turns heads & gets your blood pumping ! There's yet to be an issue w/ these cars that hasn't been solved here in this community during my 308 tenure ship. It's a great resource !

Godspeed

 

One thing you can do is reset the throttle cable, then perform a hard reset - do a forum search for both jobs, less than 5 minutes should put a grin on your face