Skidmark,

You might consider an entirely different option. You don't have an xk8. If you are going to cut into the hood, why not consider installing a set of vents that will set your car apart from all other xk's, including the xkr? Grantley design sells these vents that look pretty slick. These attach with an adhesive provided by them. The vents can be held in place, until set, by a set of clamps shown in the link below.

INMHO, putting vents on your car to make it look like an XKR is kind of like the guys in the seventies that would trick out their V6 Mustangs with chachkis and paint to look like a Boss 302, one of the baddest muscle cars of that decade. They didn't really fool anybody. Again, this is IMHO.

I plan on putting these vents on my XKR just to look different from other XKR's.

Sealey Suction Clamp Set 6pc Holds Trims & Badges RE006 | eBay

 

I'm just doing it because I think the cosmetic enhancements to the XKR look really good, and are relativly easy to do. Not trying to fool anyone, I will leave all the XK8 badges and markings intact.
Checked out the Grantley hood louvers and I like the OEM much better, but thanks for the suggestion! I may do the louvers or I may not, still up in the air on that one.

 

As quoted by Xenophobe
I'm not arguing with you, I agree and so does Jaguar.
Here's the actual press release from Jaguar,

(See Avos Post Below)
Thanks Avos It was there when I left Yesterday.

 

The picture didn’t show, so I took the liberty to highlight the part of interest:

 

Some engineering material or something similar from Jaguar would sure be useful in settling the question of what the louvers' design rationale was. Anyone have access to that sort of thing?

 

Ok.

So I was more right than everyone else.

Oh, and I'm still seriously considering the purchase of one of your twin screw kits, however the new harness for the Chevy motors is leaving me undecided on what I want to do to hit past 550hp.

 

I missed this, simple answer is yes, easily removed



And I will still disagree the vents do anything (OK they do little) to reduce lift.
I don't think anybody was disagreeing you had read it somewhere, the disagreement was the validity of the statement, Jaguars bit of literature blurb is just salesman BS, like has been said, the XK8 is no slouch and not that far behind the XKR, so why does that car not have the vents and rear spoiler. Then again it also says they are for cooling, at the end of the day we could argure/debate this until the cows come home...... So lets just agree to disagree

 

Personally I also believe it mainly aids in extra cooling. The R has an extra radiator for the intercooler circuit, that in itself already hinders airflow compared to the 8, and next to that the (h)eaton also heats up that radiator.
I can see that by getting air out of the hood at that place could aid in more down force, but am also no aerodynamics specialist. The cows are going to have great day out on this one ;-)

 

I can attest to the idea they aid cooling, but by how much exactly, I can't be sure. When I am sitting at a red light or in a traffic jam, the car in front goes all wobbly through the heat haze pouring up out of the vents.

 

I spoke to a custom BMW shop owner yesterday where they outfit cars for racing and he said that unless a speed in the 200mph zone is achieved hood louvers do little to reduce any lift forming under the hood.

 

Yeah, they pretty much are that far behind. The comparison is really night vs day.

While the XK8 can go really fast, the XKR is much faster.

The XK8 (especially the early ones) came with pretty crappy wheel size... Not that the 8" wide Pilot Sport A/S is a bad tire on a 17" rim, it's just not a good wheel and tire combination on a 4k lb car especially if you're driving very fast on very mild twisties. Also the much more slack shocks and softer bushings are more for comfort on an XK8 that don't do it justice in those situations. Also, having nearly 1/3 more HP really helps the XKR when it comes to helping it be more nimble.

It took me all of a couple of weeks to find the limits of the XK8. It wasn't really hard reaching them. I've yet to even come close to the limits on the XKR.

And all the people saying "oooh, it's almost as fast..." forget to add the part "in a straight line...".

The XK8 handles and drives well for what it is. It's a FUN car to drive. I know when the rear tires are going to break lose, it's very controllable. When you feel the tires flex it's exhilarating but it's not a trait you want when driving really fast. The 290-ish HP rated 4.0 is anemic for a vehicle in it's weight class.

The 4.2 SC is nice, but it's still a bit underpowered for the chassis, IMO. Somewhere in the 425-450hp range would really shine, or maybe slightly shorter gears in the rear would help a bit as well. I dunno as I don't know the ratio, but seeing how it's a GT car, I would think they're on the taller side... anyway, back to topic.

Of course, we all know that the hood louvers were added for one reason alone, because it makes the car look much more aggressive and a visual cue that spending the extra $$$ is worth it.

As for the need for extra cooling, that's BS. How many cars that come in both a non-supercharged and supercharged version that has hood vents to compensate? Seriously... lol

 

16 inch OEM rims on a XK8? Where'd you see that?

 

Oh, wait, I guess they're 17 inch. My point still stands though.

 

Do you have the Part# and price for the hood louvers??... considering this on my vehicle.

 

200 MPH sounds about right to me....only another 40mph and what about $20K invested to get there right, XKRacer and Avos?

"I need a car that fast to get to work on time" - Bill Cosby

Skid, skid, skid....just break down and get an XKR man.

What are you afraid of?

If you are going to go fast you might as well go Super Charged fast.

Anyone have a good Silver XKR coupe they want to give Skid a good deal on?

Skid did you already put the louvers on or is that your mock up photo.

For my money if I was going to do it I would put them closer to the windshield....like the E-Types were...always enjoyed seeing those from inside of the car....can't see them inside of the XKR unless your head is higher than the top of the windshield....just saying...after all you did say you weren't trying to fool anyone, you just like the look of them....try it....move your mock up to the same position as on the E-Types and see if you don't agree with me.

As for the lift vs. cooling argument who cares?

They look great!

Isn't that 90% of why we buy XK's?

cheers,

jj

 

They were installed about four weeks ago, and yes the signature pic is real. The louvers were placed within 1/3" of the factory position to avoid cutting thru the hood supports and increase the odds of a successful outcome. Cutting finished metal is a risky thing. Less metal to cut thru the better.

I test drove an XKR and found the high pitched impeller sound unpleasant. The car I have now is almost as fast as the XKR I test drove. A Jag tech who drove it said it's the fastest XK8 he's ever driven. It's very thirsty, too. I think its performance may have been enhanced by some means. Chipped maybe, or something else, not sure.

 

Skid;

Great job on the vents man....brave cutting through the hood.

Sounds like you had an extra noisy XKR....try another one....there are solutions for that....there is a company in Florida that I got a treated Super Charger from last year for the MINI that greatly reduces SC whine....not to mention XK Racer's top secret twin super charger mod (at least I haven't seen it on anything yet) and Avos twin screw super charger.

cheers,

jj

 

What did you pay for the louvers?

 

Got the pair of them from salvage for $80 including shipping off ebay.

 

good deal. thanks!