2 Simple Questions

Both are related to the Jaguar ('84 XJ-S V12)

1-The gas mileage on this thing is terrible, but cylindres are aplenty. What I want to do is buy a chip that could shut off 6 of the cylindres at the flip of the switch. Would this be possible? How much money? What kind of mpg improvement?

2-The airdam is all busted up. It's been cracked and bent ouf of shape for years. The cracked ends are held up by a piece of wire. The airdam also bottoms out on virtually every grade it encounters. But I'm worried that removing the airdam would reduce the amount of air flow into the engine and hence the engine could overheat more easily.

Attached is a pic of the front, you can kind of see the broken airdam in the pic (it doesn't look bad in the pic, but trust me-it's really beat). I'll try to take a better one in the meantime.

Thanks in advance. :)

i dont think u can turn off six cylinders with just "a chip" and a "flip of the switch" :(

[QUOTE=d-quik]i dont think u can turn off six cylinders with just "a chip" and a "flip of the switch" :([/QUOTE]
the guy who used to drive me to school in leb used to have a van that he could switch between 6 and 4 cylenders

[QUOTE=d-quik]i dont think u can turn off six cylinders with just "a chip" and a "flip of the switch" :([/QUOTE]
The technology is there, but how difficult and expensive it would be to install is the key. I use 'chip' and 'flip of the switch' in lamens terms, of course. ;)

[QUOTE=white devil]the guy who used to drive me to school in leb used to have a van that he could switch between 6 and 4 cylenders[/QUOTE]maybe the tech came with it?

[QUOTE=d-quik]maybe the tech came with it?[/QUOTE]
This tech is being implemented on Cadillacs and Chryslers. I'm sure there must be a third party somewhere...

I've never heard of a chip you can put in to do that. When they say the cylinders shut off, it doesn't mean that those just sit there and pump air, the cylinders all in a sense take turns in firing and not firing. So you need direct injection or individual injectors, and I don't think the jag has those. I would say you'd be better off selling the jag and getting some kind of toyota or honda that gets good mileage.

[QUOTE=johnnynumfiv]I've never heard of a chip you can put in to do that. When they say the cylinders shut off, it doesn't mean that those just sit there and pump air, the cylinders all in a sense take turns in firing and not firing. So you need direct injection or individual injectors, and I don't think the jag has those. I would say you'd be better off selling the jag and getting some kind of toyota or honda that gets good mileage.[/QUOTE]
For the few pennies it's worth I'd rather just keep it. ;) I'm not surprised I'm incapable of doing such a thing.
Thanks for the answer.:)


How about the airdam?

Try taking it off and see if it overheats. If it does, put it back on. :)

[QUOTE=Esperante]The technology is there, but how difficult and expensive it would be to install is the key. I use 'chip' and 'flip of the switch' in lamens terms, of course. ;)[/QUOTE]
Does the Jag use modern sequential EFI, or old-tech constant flow?

How could you modify the existing fuel distribution unit (or injectors) to selectively close off supply? It'd have to be V6, not cut off one bank. Without totally re-engineering it at obscene expense, I rather doubt it

Airdams can modify airflow up & through the radiator, instead of it flowing underneath. Also for reducing frontend lift at mega speeds. Seems you don't want to spend $$ on a replacement, so there's only one cheap way to discover whether removal might cause overheating .. :D

Obvious but rarely observed. Plan your driving; distance, traffic, distance v traffic, and lump errands together, etc. Some one might be getting 40 MPG but if they are constantly running around they're burning a lot of gas regardless of MPG. Keep the Jag for really driving and get a moped/scooter for errands. Nice Jag, btw.

Your airdam is probably bent backwards from all the impacts, maybe just pulling it out would solve problems. Try and find a good side-on front picture if a similar jag and compare profiles.

yeah, for selective displacement, you would need to mod a lot of physical components of the engine. however, you may be able to get a chip reprogrammed to increase fuel efficiency, but it would be at the cost of performance

Get a motorbike for around-town use and commuting, use the Jag for swaning about with as much pomp and circumstance as possible. :p

I would recommend getting a new air filter, something like a K & N