Hi Forum, I've been away for a while, having a blast with the XKR. My latest fiasco was going to Flagstaff and back with my son...for coffee. My wife is learning not to send me to Wal-mart for anything. No telling which Wal-mart I may go to. Anyway, I ordering/starting to mod out this week and I couldn't think of a better place to get expert opinions....you guys are AWESOME!!!! So here's where I'm starting:

1) Rear Diffuser from Mina Galleries (just think it would look cool on the XKR)

2) Exhaust from Paramount Performance..probably Quicksilver(I'd love to hear you guys weigh in on that)

3) Tune and upper and lower pulley from Eurocharged in Houston, (from all the hoopla about tunes and pulley mods, I get the impression you guys believed this is best place to go. Correct me if I'm wrong. Scheduling this for next month)

4) BMC filters ( I'm told they would work better than an cold air intake. (Please let me know if you agree/disagree.)

5) Killer Chiller. I believe Ghostrider said this would be a good investment if I was to do the lower puller, which I've decided to do. I have a question though, would I still be able to use my AC to cool the cabin and would the AC have to be running in order for the killer chiller to work?

6) Spacers. I have 19's on the car now, but am planning on getting 20's. I don't want to lower the car, but would like to push the wheels out a little. Maybe give it a wider, more aggressive stance. What size and brand spacers to you guys recommend? I do not want the wheels to rub.


Well, this is what I'm doing to the car over the next 30 days. I'm going to start ordering stuff as soon as I get you guys feedback. I think ultimately, I would like to get as close as possible to 700 HP.....but keep it a daily driver. Not even sure if that's doable, I'm not very mechanically inclined when it comes to cars. But I think that's a nice number when someone asks, "how much HP does she has?" That an my brother-in-law is always bragging about his 600+ HP 'vette. It would be nice, very nice to shut him up. Thanks forum. I look forward to your feedback.

 

Sorry, I needed to upload some "before pics" I guess. Well, there they go....Just an average, if there is such a thing, black w/charcoal interior XKR.

 

Think about a mild lowering and spacing, once you get the 20's, too. Very nice look. Was just at my dealer and the manager himself was very complimentary about the look... It will tighten up the ride a bit, but I personally like that, especially in the twisties. To each his own.

 

Hi Bruce, Thanks for the feedback. How far did you lower yours? Also, with the 20mm spacers, do you get any rubbing in/on the wheel well?

 

I have most of those mods and will fill you in when I have a little more time tomorrow.

Gorgeous car BTW!

 

Thanks MaximA, I appreciate it...looking forward to your post. And thanks...

 

I love what Max has done to his car to make it his own. Especially the HRE wheels--IMO no other wheels look as good on the XK. I'll be following your progress. You're in good hands with Max!

 

H&R spring kit lowers about 1.3 inches. With that, plus the 20mm spacers I rubbed slightly on driver's side rear. Turned out the rub was on some hang-over carpet from the trunk. Trimmed it and no more rub.

But do get an alignment after the install. My tech was able to get the rear end in spec after install, but it wasn't a snap. Front was easy.

Lowered, the car feels sharper, turn-in quicker, road feel better. But one man's road feel is another man's "too harsh for a Jag" ride. Probably would not do this if I lived in Detroit, but for decent roads or the track, I like the mod just for the driving, let alone the looks.

 

bklynchris,
Within a week or so, I should be getting a 2010XKR where I plan on doing many of the same modifications. I love the stance of forum member Ghostrider's car, complete with the Mina RS side skirts and front valance. But I'm smitten with this rear bumper/diffuser:
Jaguar XK XKR XKR s Rear Bumper | eBay
I like the body colored versions as opposed to the black/carbon fiber contrasting look (the blue car vs. the red one). I have everything reserved, just don't want to pull the trigger until the deal is done. Have fun and keep the posts coming, I'll do the same with mine (if and when I get it). Here is a more current link to the rear bumper/diffuser. (I don't like the exhaust tips as they don't fit the opening very well, and it's orderable without them for $400 less)
Jaguar XK XKR XKR s Rear Bumper Exhaust Tips | eBay

 

Here's a better look at the bumper with round tips as will come with the Mina exhaust that I have coming.

Jaguar : Jaguar XKR set 2
(Scroll down to the pictures and look at the 4th picture on the right. BRG rear bumper with round exhausts)

 

No need to think about spacers if you are going to get new 20" wheels. Just order the correct offset for the wheels to move out.

From pictures, it seems to me that most available springs, Mina, H&R drop more than the advertised 1.2 or 1.3 inches. My thinking as of now is to simply cut the existing front springs for a moderate drop 0.75 - 1" at the wheel center. That would likely stiffen the front spring rates about 10 percent, more than enough as I think that the XKR already using springs that are too stiff for (particularly at the rear) ideal handling.

I would not touch the rear because there is no way for camber compensation there. The slight lowering on the front should give better turn-in, better visuals as it would introduce a slight forward rake in the stance of the XKR, which would result in an other extra 0.5" drop at the front lip, given the degree of rake.

Also, if you have the adaptive cruise, be prepared for having to have the dealer readjust it if you lower the car. I've seen at least a couple of posts on these forums indicating that the lowering will throw the adjustment of the bumper-mounted radar unit out of whack. The bumper has to be removed for the calibration.

 

Chris:

If your going to order new 20" wheels, contact Ian Pavelko at Fastco.ca. He made my 20" wheels for my XKR with a exact fitment. He can also advise on fitment for offset to bring the wheels out a bid for a wider stance, when looking from the rear end.

See this thread.....

https://www.jaguarforums.com/forum/w...-brand-112076/

Also take a look at my Braelin 20's on my Jag XKR Portfolio Edition.

Jaguar XKR W Braelin BR02 2009 Slideshow by sonewmexico | Photobucket

 

Those are very nice... I thought I had a direction I wanted to go, now I have to put that diffuser in the equation. I have a black XKR, but no carbon fiber on it. I'm thinking to go with the with the black one (red car). The body colored one does look better and I would go that way if I had a different color car. I'm going to think it over for a day or 2 and will let you know if I decide to go for it. I'll keep the posts coming. I want to mod out pretty quickly here....for the summer. I must truly be a bid kid. LOL

 

Definitely better with the round exhaust tips I agree. I'm going with the Quicksilver exhaust, so the tips are pretty big....98mm I think. Those would look pretty good with that diffuser

 

Great advice axr6. So I guess my plan of attack should be getting the offset wheels first, then seeing if spacers are needed. I'll also look into cutting the spring as opposed to lowering it. Of the two options, lowering or cutting the spring, does any one take away or add to performance (handling) more or less than the other?

 

You have one gorgeous XKR...let me tell you...That car is a thing of beauty!! I checked out Braelin's site and the other post. Great deal for on the wheels. There is a custom wheel shop here is AZ that everyone raves about. I think I'm going to check them out 1 day next week and then make a decision. The Bralin's are in contention. Thanks for the info.

 

Generally, when you lower a car stiffer springs are needed as the total available travel for the shock absorbers (struts) are greatly reduced. In the case of the XKR I believe that the stock springs are more than stiff enough to sustain at least 1" of lowering without any risks of shock bottoming. As I stated, when you cut one turn out of an 8 turn spring, your total spring stiffness will increase about 10 percent. So, IMO, plenty enough.

The issue I am having is that the springs that forum members have used (with the exception of Ghostrider and the coilovers of MaximA) appear to lower the car more than what I would like. They leave very little available shock travel. I looked up Adamesh of UK that supposedly sold 15 and 25 mm springs but all I had seen on their website was the 30mm being the least. So, if I want less I have to cut my own. I do not worry about messing up the springs because if I do I can always purchase a new set of stock springs for about $82/spring. That is a cheap experiment, as far as I am concerned.

The reason I do not wish to lower the back because the rear wheels have non-adjustable camber. Some member (SoCalBabe) reported nearly 3 degrees of negative camber after lowering, which is WAY...WAY too much. It will eat the inside tire edges and will be far from ideal in street use because the tire surface will not be sitting nearly flat on the pavement.

The best solution that I have seen is by MaximA, using the coilovers, which are fully adjustable for ride height. Still, he has 2.2 degree camber in one of the rear wheels, which is still too much. Also, I am not a fan of the much stiffer rear springs the set came with. After experiencing the first loss of traction under cornering/accelerating, I am more convinced than ever that the overly stiff stock springs are the cause. Softer springs would provide better tire traction at the rear.

I have not seen the spring configuration off the car, only on the car. The only thing that could pose a problem with cutting the stock springs if the spring-ends would be flattened. That would be difficult to reproduce in my home garage. From the looks of it, that is NOT the case but, I have to reserve the final say until I actually take it out hopefully this week.

Also, I have done this before successfully on two cars, one being a Lamborghini for which no aftermarket lowering springs were available. In those instances I cut all 4 springs as I had suspension adjustments to compensate for the effects of lowering.

 

The Mina quad exhaust tips are fabulous that is what I have on my 2012 XK vert. When I got the Mina exhaust system, those are the tips that came with it.

 

Ralph,
I am getting the Mina exhaust for my car, and the tips are nicer than the angled ones shown. It should look quite similar to the photo of the BRG coupe with the round tips.

 

Here are my thoughts and I'm happy to give you more information if you like.

1) Rear Diffuser from Mina Galleries (just think it would look cool on the XKR)

I ended up ordering the stock rear diffuser as the Mina part just didn't fit correctly and I couls see through the CF at some points. I'm just extremely picky and maybe this will be OK for some but I want my CF perfect as possible. I also didn't like the fiberglass end pieces as they would chip much more easily then the bendable factory pieces. Mina makes good parts and has great service but this part was not up to the my standards.
.
2) Exhaust from Paramount Performance..probably Quicksilver(I'd love to hear you guys weigh in on that) This really depends on what you are after and expect in sound. Some have said Quicksilver is perfect in sound, others to loud. I think that if you have the standards exhaust, get the center resonators replaced with an X-Pipe and go from there.

3) Tune and upper and lower pulley from Eurocharged in Houston, (from all the hoopla about tunes and pulley mods, I get the impression you guys believed this is best place to go. Correct me if I'm wrong. Scheduling this for next month) Your just going to need the upper pulley(don't think there is a lower pulley for '10+) for 1.5lbs which will net you 11lbs of boost max with the the tune. I'm very happy with the results from Eurocharged and their service has been good as well. I got around a 73HP gain total with pulley and the tune.

4) BMC filters ( I'm told they would work better than an cold air intake. (Please let me know if you agree/disagree.) The XKR already has cold air induction as its pulls air form the lower two intakes on the front of the car. I added the BMC filter after my tune so its hard to tell if it made a difference. Now the dealer did overwrite my tune a few weeks ago and I ended up at the track with no tune and BMCs. The car was about .7 MPH faster in the 1/4 mile but who knows if that was environmental factors such as temperature and humidity or the filters. I have no doubt they flow better then the stock paper filters but think they are probably good for 5-7HP

5) Killer Chiller. I believe Ghostrider said this would be a good investment if I was to do the lower puller, which I've decided to do. I have a question though, would I still be able to use my AC to cool the cabin and would the AC have to be running in order for the killer chiller to work? Not sure about this but since its steaming in south Florida during the summer I must have A/C

6) Spacers. I have 19's on the car now, but am planning on getting 20's. I don't want to lower the car, but would like to push the wheels out a little. Maybe give it a wider, more aggressive stance. What size and brand spacers to you guys recommend? I do not want the wheels to rub.

Get wheels with the proper offset and you will not need spacers. Soon as I get to the office I'll dig up the offset of my wheels. They sizes are 20x10 fronts and 20x11 rear. Depending on the style of wheel you want you might end up with custom wheels so make sure the offset is spot on. I just looked at my offset and its ET45 front and ET40 rear. That brings the tires out as much as possible while still clearing the arch. Keep in mind my car is lowered ~1.2 inches so at stock height you may get a way with a little more.