I find it hard to believe that you guys slam a Jag with a SBC engine but feel a rotary or diesel engines are ok. Seriously a friggin diesel.

 

If you haven't been in a German luxury diesel lately, check one out. They've come a LONG way since the 80s.

I used to think the same thing.

 

This has got off topic a bit.

But check out the Audi A6 biturbo diesel 1990kg 6.4l/100km (37US mpg) and 0-100 in 5.1sec

 

A diesel Jaguar XF is only 0.2 seconds slower to 60 mph than the 5.0 V8 XF and uses half the fuel. Over 500 ft-lbs at 2000 rpm is very usable.

If I handed you the keys to a new XF V6 diesel and told you to take a test drive you'd never know it was a diesel - as indeed my passengers thought it was a gas engine and were very surprised when I pulled up to a diesel pump to refuel.

 

I like your thinking. There is nothing like a V-12 that can breath. Too bad Jaguar never allowed there's too for us common folk.

 

A buddy came by in his '08 Bentley sedan - W12 twin turbo. Not as fast as I expected, although it's a huge car. Nice exhaust at startup (custom) and idle, but too loud on the freeway.

On topic: I would also put that powertrain in the XJS. Too pricey on eBay though.

Merc twin turbo definitely looks like the swap...

 

I know new diesels are much more efficient and more powerful these days but as a practical matter no-one is going repower an XJS with a modern diesel. The electronics package, engine controls, integrated instruments, and emission devices make repackaging into an XJS or any other car for that matter a hair shy of impossible.

My 6.7L SBC 450HP mid 12 second convert manage 19 MPG on a recent 500 mile trip. The best my old Merc 300SD could manage on long trips was 25 MPG with the injection rack adjusted so it wasn't a total slug.

Let try to stick to reality hear on earth. Back during the bad old days, (5 years ogo) when gas was nearly 5$ a gallon there was interest in economy SBC's, there were more than a few guys building "performance" 4.3 chevy V6's and 265CI SBC's. With the right gears and transmissions, performance was adequate and MPG was in the low 30's. That was an interesting time but with gas in the low 2$ range and the economy relatively good here in 'Merica big blocks and boosted LS engine are all the rage.

 

iscamerica,, you mention "stick to reality".

have you ever given thought that my reality and yours are different realities?

in a free thinking enviorment each generation has a different reality, that very thing is what makes the USA a GREAT country!

 

and if i did have an AUDI V12 Diesel engine , you can best believe i would make it all run!

i did my very 1st engine conversion when i was 16 yrs old, with some help from my best friend 16yrs old.

and YES we did not know what the hell we were doing, BUTT, we did it anyway!

a 1937 Lincoln coupe V12 , out with the 12 and in with a 1946 Mercury V8, and it ran perfrect!

 

1. Quite a few of the Zephyrs got V8's, Ford or Mercury.


2. If Chevrolet is beneath the "dignity' of a Jaguar owner, just get an LT1 sourced from a Buick Road Master or Cadillac Fleetwood Brougham.


3. I was just reading Road and Track. Getting hard to read that soft type
on glossy paper. But, as a long time Ford addict, I was drawn to the current GT40. A comparison of the Lemans racer and the civilian car.
Slick beyond bounds. But, Ford chose their V6. Well capable of way the h.. past 200 on the Mulsane straight!!!


4. Shelby's Terlinga place messed with Mustangs. One a race car powered by guess what, the V6. A guest pro driver was impressed.


5. Way the h... back, a guy that lived in a town down the road went to INDY and raced. His mount different from the Offy's. Cummins diesel.....


6. My son bought a well used, but well cared for 3/4, 4x4 Dodge pickup.
Cummins power. Mileage is way up there and it just clatters away and tows anything attached to it with aplomb....


Carl


Carl

 

Well, see it from this side: the V12 is a special engine. It is not an engine ypu get in every car on the road. Most common only in luxury cars, like Toyota Crowns (for the Emperor), Ferraris, Lambos, ... So it makes it a special engine.

A V8 on the other hand is basically the American Version of the European 1.6l 4 cylinder. Available im basically any car, no matter if small, compact, midsized or even some luxury... So it isn't anything special.

V8s are lovely engines. I enjoy my 3.2l Jaguar V8 in my XJ when it runs... But then again, the V8 is getting extremely common here now. Especially since muscle/pony cars are sold normally instead of via Grey Imports. Even Volvos were sold with a V8. The former specialty and rareness has gone.

So I think replacing a rare engine with a common engine is not the right thing - though I have nothing against a V8 conversion if it is done properly. Instead, I would replace rare with rare. A V12 TDI is a rare thing. A W12 (well, actually a dual VR6) or a wankel is a rare motor. Again, rare = rare. Stuffing a 2JZ into it isn't special. The 2JZ is just the tubers choice. A Boxer 6 from Subaru with twin turbos would be neat, but it is too wide.

I like the idea of stuffing an LS1 into a 911 Porsche. Best idea ever!

 

A buddy of mine stuffed an LS1 into the BACK of an AMC Gremlin. Yep the back... So a LS1 into a Porsche can be done. Ohhh the purists are rolling their eyes now. My buddys Gremlin is gone but surely somebody has a picture of a lumped Porsche.

 

It is actually quite a common thing. Especially in the 996 with bad engines...

 

Porsche with LS1 power. Yahoo, let's go!


Circa the mid 60's I worked in LA. I hired a guy that had been fired, for good cause, by a competing company. He professed having reformed.


It worked out. Did his job well.


He latched on to an early Porsche. Blown engine. Out with the VW based flat four and in with a GM Corvair flat 6. Much better, in many ways...


He also had a boat powered by the "little hemi" a Dodge Red Ram. We conjured a "high rise intake". Welded up long runners to a plenum. Toped by a four battle carb. Poor idle, but lottsa high end. Great for towing skiers. Not me, though!!!


I think we missed a big marketing opportunity or two!!!


Carl

 

semantics...Until someone actually puts a modern v12 diesel in a XJS it's a fantasy...not a reality.

I dont think much of describing america's greatness or exceptionalism as just a function of free thought. It's thought and ACTIONS. Elon Musk is getting it done. Edison Got it done. JP Morgan got it done. John Rockafella got it done. Eli Whitney made something. "Free thinking" only gets you so far. Mike Tyson said..."Everyone has a plan until they get punched in the mouth".

So Ron...buy that diesel, wrestle it into the XJS and let it punch you in the mouth a few times. If you do you'll be amoungst the realists, until then you're just thinking.

 

NOW,NOW your Italian is showing!!

 

Nice

 

i am on the tail end of a v8 swap on my jag, been working on it on and off for probably the last 6 months. one could probably be done in a couple weeks with all parts on hand and time to work on it. built the engine over the winter, witch is a 4 bolt main 350 .10 over bore modified vortec heads (valve guides and seats cut to accept larger valve springs and lift) rocker studs and roller rockers. some very mild port work on the exhaust side (mostly profiled the guides and opened up around the guide a little) its got a gm performance lt4 hot cam in it. witch is a split duration .500 lift cam. this combo should be good for right around 400hp. i had the core engine sitting around put about 2k into the engine.

then the project sat around a bit waiting on me to get some time, then i worked on it a week straight yanked the jag engine shoved it in the car with a used will blow 700r4 using a set of jags that run mounts. engine sat right in place. i think if i built mounts from scratch i would have set the engine back a little further but i didn't really want to do the engine in out 10 times on this project so i wen't with the conversion mounts. everything bolted right up no real complains. the jags that run book isn't the best guide for a 93 xjs but i have some wiring schematics for the car wiring is pretty simple. the only thing i felt was garbage of the mount clips was for the trans linkage i threw that in the garbage and made my own.

in a weeks time i removed the old engine installed the chevy engine wired it all driver controls modified the drive shaft and built my exhaust system modified the fuel system all gauges work, shift linkage throttle ect. only thing i have left to do now is Finnish the cooling system and front engine accessory's should get its first test drive in a couple days.

i suppose i should mention that i am temporarily deleting the ac. my jag is a play toy to me not a daily driver. i will add ac back to the car later though after the car gets a good shake down and ironed out ill start collecting ac parts.

biggest problem i foresee is hood clearance i have not set the hood on the car yet but its going to be tight and there isn't a whole lot of intake manifold options for vortec heads. so i might suggest a good flowing set of aftermarket heads that use the standard intake bolt pattern rather than the vortec heads.

 

also if anyone is interested i have a good 93 I6 and transmission (car suffered from a electrical fueling issue before the swap) also have a new mass airflow meter fuel pressure regulator a few good used crank position sensors and various other parts ill be looking to put up for sale soon.

also if you need some parts like injector clips to repair your stock harness i have a big pile of that stuff too.

 

Interesting swap. My swap using an LT1 from a Cadillac Fleetwood Brougham challenged me. But, albeit imperfect, it is reliable and a ball to drive....


Carl