new to jaguar ownership myself.been looking around the site and just wondering what are some common power upgrades you guys are doing? also wheres good places to buy parts for our car?good brand names?

 

what xj did you get? xj8 or xjr?

 

crap, my bad its a 2004 xj8

 

Not much you can do to get more power. These are very well thoughtout cars and finnicky when it comes to tinkering on.

Personally, I would rather have reliability vs. a few more ponies.

 

The common thought on this is to jack up your radiator cap and drive an XJR under it! Other than that, change the fluids, filters and plugs, put really good tires on it and go have fun.

 

I would say exhaust, drop a k&n filter in it, other than that keep it tuned up, plugs and fluids. You could come to the midwest dyno tune day

 

I totally agree! And if that's not fast enough, jack up the radiator cap of the XJR and drive a ZR1 under it. If that isn't fast enough then start looking into mods.

 

haha fellas thanks i get the message.im totally happy with my new to me jag and its power.i was curious about what you guys were doing.looks like proper maintance should keep me rollin and happy.

 

Apologies - Didn't mean to come off as having fun at your expense. There is truth/wisdom to the responses. If you're looking on the used market at, let's say, an 04 XJ8 compared to an 04 XJR, the cost differential might be $5000 to $7000? Don't quote me, just guessing? There is a 100 HP difference between these two cars. So, another way of looking at it - can you add 100 HP to a stock 04 XJ8 for $5000 to $7000? Then, if you can, why would you do that and ba$tardize the XJ8, when you could have just bought the 100 hp for $5K/$7K in the first place?

Being on the technical side, the NA 4.2L motor is engineered very well for a 300HP engine. It is very difficult to find latent HP the designers left behind. I can tell you, there is nothing left in the intake air box leading up to the TB. There might be a few HP on the downstream side of the exhaust. You'll easily spend $2000 + (of the $5K to $7K) just on a performance exhaust to get maybe 10/15 HP. So, you'll find yourself looking to the engine internals hunting very expensive HP in head flow characteristics, or engine components that do not exist in the aftermarket.

So I don't come across as old/stuffy, I've chased HP in cars all my life, and found lots of it "in the old days", when designers really did leave HP on the table, but it just doesn't exist here, except that Jaguar designed one for you completely done called the XJR (or XKR in a coupe/convertible).

Then, if you really want to go fast, compare the price of a new ZR1 at around $100K to almost anything for sale. You can have HP by the boatload and 0-60 times that are among the fastest times on earth for the same price as a new XKR....if fast is what you want.

Apologies too for the length, but hope this helps clarify our sophomoric replies.

 

Everyone pretty much mentioned everything worth talking about, especially about the jags being tuned efficiently from a HP stand point. It's a case with a lot of drivers. I have an XJR and I would want quicker 1/4 mile times. Would it be fun, yes, but necessary, absolutely not. It's something about knowing that if there are tuning options for the car, you can always do them, even if you never do.

To answer your question, The only tuning companies I found were Minia Gallery, and Eurotoys. Both seem a bit $$$