Visual difference between a 2.8 and 4.2? Just checked out a rust free 73 california car

Hi, I’m not sure what else to task. I checked out a 73 XJ6 today, and I’m new to jags completely. I have owned british cars before, but not a jag. Popped the hood… triple carbs from an XKE, supposedly? Also, it was originally an automatic, and the original owner converted it to a manual trans.

What’s it worth? Here are some photos:

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If you mean a 4.2? and a 2.8 ? Look at the rear of the cylinder block. You won’t see a flat plate bolted on the back face of the block facing the firewall. That’s because the 2.8 is a shorter stroke engine so the block isn’t as tall.
The plate is basically trapezium shaped held in place with 1/4” UNF bolts.

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Yeah, sorry, 4.2. Did you check out the photos? Manual trans S1. Rare? Desirable? Valuable? How much?

I really wouldn’t have a clue, sorry I’m in England. I think a manual adds value, it does over here. The triple carb set up is unusual on an XJ6. But think it would only make the car worth a bit more if somebody had a pair of the original SUs and manifold to fit to it.
The triple carb manifolds have a value as lots of people like to ditch the lovely twin Stromberg set up on thier E types.

Another tell tale may be the tacho? I think the 2.8 might have a higher rev limit due to the shorter stroke?
Being a converted car may weigh against it as far as value is concerned.

Yes, I think a 2.8 has a 6000rpm and a 4.2 a 5000rpm. Also ask if it has an overdrive! Ordinarily there is a little switch on the top of the shift, if it’s a retrofit it might have some other arrangement. Paul.

Nice to see. Interesting.
Some enthusiast got a hold of it at some point down the line.

sure. To me it is.
…not going there again. To me it is.

Definitely worth putting out there for someone to bring back to life and save.
Not enough of these around.

Perhaps I am out of line as I have no affiliation, nor do I know if he would have any interest, but there is a reputable and kind fellow, an apparent professional mechanic, who seems to focus on S1 XJ6s and has a genuine love for them on BringaTrailer bringing them to life and flipping them. Goes by RoyDestroy.

For some reason my intuition brings him to mind. It would be neat to see him bring it back to life and make it available to the public. He is also in California. Perhaps he’d have an interest.

This could become a neat car.

The tach is 4.2, not 2.8. The gearshift lacks overdrive switch, possibly relocated. Engine looks like 4.2, certainly not 2.8. Value? Imposdible to say. Needs a lot of work to look tidy again.

Someone loved this car, Rob - why does he sell…?

Mileage is a factor, and does it run? Some background checking may be interesting - it might possible be factory optional, shown in the car documentation. What gearbox is fitted? The triple carb set-up is arguably the most powerful version of the xk engine - which may be attractive…

If you want to keep the car; take it - if you want to sell it on it may not be worth buying…

xj6 85 Sov Europe (UK/NZ)

Looks like a dog to me; obviously converted from auto as console is different in a manual and pedals are wrong(too wide). Also, as mentioned, if o\d fitted, should have switch in top of gearlever, if not, simple round knob. Would be valuable if original, but IMHO, looks like it would cost more to tidy up than it would ever be worth. Also, as mentioned , triple carbs are worth money, but depends on whether the inlet manifold is E Type or Mk10\420G. The difference is the E Type manifolds “step downwards” as in , when viewed from the front the carbs are lower than the inlet port, whereas the Mk10 ones are level. This is for clearance in the low bonnet of the E Type. The Mk 10 setup won’t fit an E Type.

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Totally agree with OldJagNut. Recently I knocked back a series 1 XJ6 with manual transmission. Price was $AU2500 but I worked out that it was a conversion done with a MkII box and whatever else was available. Shame as I would happily pay $5000 for an original manual car, no matter how bad the condition.

No matter how bad? There’s a 2.8 mod in france that I didn’t buy, it is a bit rusty (doors,…) but the clutch is said to be new and the engine is alright. €2500. the seats look like new and it is rock bottom base condition except radio… quite cool. Problem is, I cant weld.
This one above would make a cool race cat!

Yes you can - you just don’t know it yet!

I had the same problem until I took myself off on an introduction to MIG welding course. All about technique - not difficult, just practice, practice, practice.


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That must be quite a late series 1 car, I can’t tell from shots if it is SWB or LWB but the SWB is apparently preferred.

Triple carbs nice to have, worth an extra 20hp and the manual box will make it feel more sporty and quicker. Both items have value by themselves. It could be a really nice driver, with some money to spend but no old XJ6 is ever a AAA investment and that ones quite non original.

If it has an overdrive in there at all, original overdrive cars had a lower ratio rear diff which may or may not have been changed with 'box. But a 4 speed on auto diff ratio was another factory option so perfectly OK to use.

The value is mainly gauged by body and trim condition, mechanicals probably less important so use those to judge value. A bad body will cost a lot more to fix than an engine or gearbox. Interiors expensive too.

Honestly, to make that nice will probably cost more than it’s worth but thats ok if it’s a hobby or leisure activity.

I recall teddycan. Aposter here, way back. a nucleur engineer. He taught himself to MIg. Fixed some real rust buckets…

Were i twn years younger, i’d consider taking on the car. Looks very interesting…

WAG. $3500.


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Welcome Rob, from another Rob.
The small outboard headlights indicates this is a USA spec car, in which case it would be a 4.2 Liter as we never got any 2.8’s here. You can look for the engine size on the right hand side of the engine block.
It would have been originally automatic and had 2 Zenith-Stromberg carbs.
It has the S2 trunk release.
Side marker lights too, some cars for other countries did not have those.
There were rubber covers on the front impact bumperette things, I believe for '73 USA only, as my '74 USA spec S2 has a full width rubber cover over the bumper.


I’d be surprised if it was a 2.8 in California. It looks like originally imported into the US and to my knowing the anaemic 2.8 litre scrooge version was not even available for the US market. Tach and engine are 4.2 litre as well.

The stickshift box transforms the car a lot. Obviously someone was after that in the past, as the triple SU setup is not easy. In general, manual gearboxes are sought for, but the original boxes were mostly overdrive boxes. It looks as if your car has been treated to some throw-in solution, however. The non-original pedal box is one give-away.

The California climate has left the original and valuable interior to be rescued it seems and the body looks very good except for the rubber strips over the doors - are they just glued or screwed on? Usually, there’s rust around the eyebrows, along the window edges, lower edges of the hood behind the wheels, inner and outer sills. The bit of surface rust along the rear quarter panels and the rear valance is easy to fix.

Would make a very interesting project for restoration to original outer appearance.

Good luck


75 XJ6L 4.2 auto (UK spec)

So far as I know, no 2.8L XJ6’s (or 2.8 anything else) were exported to the USA.

I might pay $500 for it. It has a tremendous amount of negative worth right now, and only hazy potential postive worth.

I had my original 14,000 72 xj6. A wonderful car even years later…
If you are in the states and those upgrades were done…its even better BUT, The car is not worth much.
I LOVE THEM, But if its NOT RUSTY and really clean, 5 grand? Maybe? remember its not original.
I personally love that , but its a very small group.
Buy it if you love it and drive it and enjoy it.