I just noticed on a youtube video of a 2005 and 2007 SV8 that I am missing the middle plastic engine cover that sits around the aluminum intake plenum. I assume it is just cosmetic and not functional? Or does it have a practical function? I also need a spare tire cover and see one on eBay at a yard in Irving TX near where my son-in-law lives; maybe they'd have the engine cover too. I bet the Jaguar *********** would want big $$$$ for one.

 

I would not worry too much. The whine of the super charger is louder and possible heat dissipation is better?

 

Hi jackra_1,

I have moved your post to its own thread since it has nothing to do with air suspension issues.

Regarding the engine cover, search the forum for "heat soak." One of our members has demonstrated that the cover may be important, at least for the supercharged cars.

Cheers,

Don

 

I apologize Don. Thought I was responding to "Missing Engine Cover".

I have read those posts you mention. From the limited data I get the impression the engine cover is not terribly important but then my only engineering background is chemical.

 

OK, Thanks for moving it for me. I did a search and found several interesting discussions (those XFR guys really go for the Jagular when they get excited) but am still looking for the one that says the cover is vital.

However, from the photos I saw, I am missing more than just the plastic cover and I saw mention of "bags of insulation" that mine definitely does not have.

http://i237.photobucket.com/albums/f...psfipeuuj0.jpg

http://i237.photobucket.com/albums/f...psgeb2ms2v.jpg

I'll keep looking but from you experts, what all do I need to get back to stock and will I do any damage in casually driving it the naked way it is now? I already drove 600 miles from Houston to Arkansas without knowing the diffrence.

 

On the underside of my engine cover there is a foam layer covered with black plastic that is glued on.
Just looked more closely. Its pinned/clipped on no glue.

 

BMW and Rover (which uses a Jag engine) call it an "acoustic cover". That implies it is mainly for noise reduction. So, not "vital".

 

Hi jackra_1,

No apology necessary. I misunderstood and didn't realize your post contained a quote from Phil, and that it was Phil's post that digressed from the air suspension theme of the other thread. I've edited Phil's posts and moved his question about the engine cover to this new thread, and I've edited your post so the quote shows up clearly (for half-blind readers like me!). Sorry for my misunderstanding.

The post at the link below from 34by151 shows his research into engine bay temperatures and how the engine cover is actually helpful in resisting heat soak:

https://www.jaguarforums.com/forum/x...e4/#post721877


I'm sure that cjd is correct, that the primary purpose of the cover is noise insulation, but for supercharged cars his research seems to indicate that they also serve another, perhaps more important purpose.

Cheers,

Don

 

Very interesting reading Don.

If I read that post correctly once you are going above 45Kph/28mph the advantage of the cover disappears with regards to heat soak.

Below that there seems to be a noticeable advantage for heat soak.

 

What material are the covers that say supercharged? Are these normally exposed or are they under the U shaped engine cover on stock supercharged engines?

 

Let me see if I understand? When he speaks of "heat soak" he means the intake and intercoolers being heated by the increase in under bonnet temperature from the exhaust manifolds, cats, and the road surface when stopped? And that the engine cover with the insulation under it keeps the intercoolers and intake plenim from absorbing that heat and thus remain cooler than without the cover at low speed or stop and go driving? But that it makes little difference at crusing speeds when air flow cools the under bonnet temps to near ambient?

 

Hi jackra_1,

We may have to ask 34by151 to clarify, but if I understand his post, the speed-related data were not in reference to having the engine cover on or off, but at what speed heat begins to transfer down the transmission tunnel:


He doesn't deal with whether things are better with the cover on or off until later in the post, where he reports:


Cheers,

Don

 

Hi Guys,

Sorry I was not reading this thread till now.

To answer the big question, yes the cover reduces heat quite a bit however heat is only an issue when stopped or at low speed. Over 45Kph it makes no difference if it is on or off. Below that speed there is little (or none when stopped) air pressure in the engine bay. So the air rapidly becomes hotter.

The heat is hottest at the top (at the cover)

What the cover does is insulate the intercoolers and inlet manifold from the heat.
It does not prevent the heat just insulate.
In other words it delays the effect of the heat.

Also to note the longer the heat is present the longer it takes to cool down.
The is where the 45kph comes in.
Heat does not go down rapidly till you reach this speed

Further tests showed having the fans on full blast is about the same as 20kph.
Its just enough to keep it cool and for IAT to lower but if it is hot will take quite some time.

All that said unless your talking performance I would not worry about it at all
It does make a difference to those of us on the track though.

Also the source of the heat is the exhaust manifolds. Simply getting them ceramic coated will get rid of most of the heat in the first place.
Assuming this has been done you don't really need any further heat protection

Hope I have covered it all
Let me know if you need more answers

Cheers
34by151

 

Philwarner's castings
http://i237.photobucket.com/albums/f...psfipeuuj0.jpg

http://i237.photobucket.com/albums/f...psgeb2ms2v.jpg
are nicely polished, but they aren't the same as mine. Mine are smaller and boxier with "Supercharged" cast into the tops. What model is in the pic?

 

Aluminum or Aluminum alloy I believe.
They are normally under the engine cover and only the center piece is exposed. However in another post is states that the hood basically covers that when closed.

Thank you 34by151 for your explanation it now makes sense to me.

 

eBay item number:231093121577 There is one for sale on Ebay for I $94.95 used

 

Mine is a 2006 Super V8. Maybe these were part of the changes for 2006? Or maybe an SV8 VS XJR thing?

Are the intakes with the leapers on them all XJR? Perhaps the individual covers with "supercharged" are XJR too?

I thought mine looked like the ribs were for heat disipation, but perhaps they are just structural - they do hold water and catch dirt when exposed like that.

 

Searching the EPC it looks like all the part numbers supersede to C2C37017.

Searching part number C2C37017 at jaguarmerriamparts.com shows their price on a brand new cover is $115.31.

Searching the same part at gaudinjaguarparts.com shows their price on a new cover is $115.78.

I always compare the shipping costs but given your location you may save a few dollars on shipping from Merriam, Kansas compared to Las Vegas, Nevada.

Cheers,

Don

 

Thanks, that's the first one I'd seen on eBay. I see it is off an 04 or 05 XJR - if XJR individual covers are smaller and boxier I wonder if the top covers are the same.

There's a yard in Irving Tx that has the spare tire cover I need and I'll see if they have an engine cover for less, but first I am calling the car lot in Houston where I bought it. The lot's mechanic told my friend that he had replaced the supercharger gaskets, so they might have laid the engine cover aside somewhere. They also lost the grill growler between the time they took photos for their listing and the day I picked it up and have not responded to emails asking about that so it is definitely time for another call.

 

Thanks, Don,

At those prices It hardly makes sense to buy a used one for $95 even with free shipping, but then again, this will never be a show car and it is under the bonnet so I'll be the only one seeing it.