Good evening Jaguaristas!

I've just bought a 240. Yay!

Has any one tried to fit EFI onto a 240 using a triple weber manifold and these

https://store.jenvey.co.uk/throttle-...-vshort-tssxxi

At only 30mm wide, they are a lot shorter than any carb.

They would need some form of airbox, plus a means of idle control and vacuum for the servo, but otherwise, could this be a solution for fitting fully sequential EFI into a Mk2 engine bay without modifying the body or moving the master cylinder.

What do you chaps think?

 

Only one question. WHY?

 

Because he probably doesn't understand how a carburetor works and with EFI, the car will easily do over 200 MPH !

 

You will need long trumpets if you want any low down Torque.

 

Drivability is one good reason. Espcially during warm up the fuelling control of the SU's was poor and the S Type's were criticized as being sub par when they were new. With EFI drivability can be close to a modern car, and you will get better fuel economy and better emissions. There is a reason no car maker has used a carb in decades and they certainly "understood" them.

 

I have no issue with TB fuel injection as long as the inlet is properly flowed & the correct length for a decent torque curve & contains PROPER air filtration.

 

Buy a modern car then with EFI. Why do so many people buy a 1960s Jaguar then try and convert it in to a modern car. So many on here are changing the engine, changing the gearbox, changing the interior, recently we had a big discussion about RetroMods and a firm that had changed the body shape of a Mk2.
So I will say it again. WHY?
I am not a ****, purist, concourse car guy. I have a modern Jaguar XF Sportbrake to drive around in, to go to the supermarket, long journeys, take the the dogs out for a walk. I also have a 1968 S Type which I use to go to classic car shows, use as a wedding car and to drive to the golf club for a round of golf. My S Type has some subtle alterations such as wider tyre, up rated springs and dampers, electronic ignition and a header tank on the radiator to cover water loss but that is about it and as far as I would want to go. Driving a Jaguar Mk2 or S Type from the 1960s is a desire,sometimes a challenge always a joy so WHY do people persist in trying to convert them into a modern car.

 

Rob ~ You & I as you well know are basically on the same page. People must do as they wish but they are generally changing the whole character of the car & it's no longer a Jaguar. It belongs in a bitsa/silhouette class. e.g changing seats ~ they look wrong & their only real claim to fame is the safety of a headrest & better lateral support. I just put down my centre armrest & I'm wedged between the door & rest so I don't slide around on pretty savage cornering. A properly rebuilt S Type seat including spring bed if necessary on the driver's side & properly re foamed is extremely comfortable for a day's run. If they are really worried about safety they should mount an impact sensor & hide front airbags at minimum. There miles of space to do so out of sight.

 

Yep, all those reasons.

Plus its one job on an old car I've never done, convert to EFI and get in amongst the megasquirt stuff, its just a challenge I fancy.

Plus increased MPG gives increased range, which reduces trip to the petrol station which is useful for me since its not nearby and is a diversion from my usual daily route.

Plus, I reckon if Jag had access to EFI in the 60's they'd have fitted it.

 

Jag did have access to Lucas EFI but decided against it. One of the Mk2 prototypes was fitted experimentally in July 1959 with Lucas petrol injection. (Credit Taylor/Whyte)

Probably just as well. Those were early days of EFI.

 

I didn't know there was EFI around in 1967 for the 240, they had the PI used on the Triumphs, in any event, even if they had EFI they didn't narrow band O2!

I must go read up about trumpet length and the effect on torque.

(In my dream world I end up with an EFI 4.2 in the car and a long range Coombs style tank, 30mpg and 17 gallons would give me 500 mile range, I'd like that).

 

Keep dreaming. Even a fairly modern Jaguar XJ8 with a 4.2 ltr sensor crammed engine with fuel injection is only doing a combined 20 to the gallon.
Trying not to be negative but why not pull the original 2.4 Jaguar engine and put a 1.4 diesel injection from a Toyota which will give you 40 plus miles to the gallon. If you get the Turbo 1.4 it will be quicker than the old 2.4 XK Jaguar engine and has a lot more torque. You could save yourself a lot of time and effort if you bought the whole Toyota and ditched the Jaguar all together. This way you could have aircon and electric windows, crumple zones and air bags. Don't know why I did not think of this sooner.

 

Why? I don’t know. Is there a rational reason for doing anything with our old cars? They are very pretty, but is it worth the effort? But then why do most things, apart from the fact we find some fun in it all? Apart from that, for me, all my Jaguars are part of the family and also, as an engineer, I get to play at guessing what Heynes and co might have done next with the cars if they’d had the opportunity. As such, I’d not rule out fuel injection.

SU carburetors are probably the best carburetors that anyone has ever made. Up to the late 1970s, they were also better than fuel injection. Overall, for power, driveability, economy, emissions they were the tops. When Jaguar used an alternative, it was a one-trick-pony when the one trick was essential.

In 2021 you can do better with fuel injection. However, any significant ‘upgrade’ to our cars should be sufficiently Jaguar. Glyn has already wisely written that there are some essentials to make the best of the FI. It needs: sufficiently long inlet tracts, ideally more than 300mm even for a revy 2.4; one or more large paper element air-filter(s); large plenum(s). And all those have to be fitted into precious little space. Have a look at the system on the AJ6/16 engines; it’s a neat design fitting everything into a bigger space than available in a Mk2.

Individual throttle bodies are a significant complication to the problem that I’d avoid. The manifold from a series 3 XJ6 should bolt to your cylinder head, but it’ll ‘overlap’ the inner wing and steering column. I’ve heard of people turning them upside down. Still it’s not the greatest manifold ever. It might be possible to cut it through the runners and attach your own suitably curved inlet pipework to the remnants on the flange end. And improvise from there.

 

There was EFI available in 1959 from Lucas. Don't run open trumpets. You will drastically shorten engine life. Forget 30mpg. They did not have narrow band O2.

 

Peter. Surely there is a tuner in the UK that provides (single) TB fuel injection & a properly tuned & flowed inlet manifold for the XK engine? Obviously the head should be flow benched as well.

 

Glyn, The close to off the shelf systems that I'm aware of fall in two groups. One uses a manifold similar to or the same as Weber carbs. They take individual throttle bodies (even ones that look like Webers). They seem to be pretty good, but are aimed at and most suitable for C, D, E-types. They have enough space. The second family, which I know less about, use throttle body injection inside SU carbs. It will simplify tuning and fit in a compact saloon, but obviously doesn't gain all the potential of EFI.

Incidentally, the Lucas system of the 1960s was electric in that it used an electric pump, but I wasn't aware of them developing an electronic system to the level of testing on a car.

 

Yes. I've seen both. Just wondered if anything else was available. The ones grafted into SU's did not over impress me. Yes I've had a look at the old Lucas system. Aston also messed with them but every car I know they tried on has had them removed as highly troublesome.

The straight-port cylinder head was only fitted from the 240 onward making it capable of a genuine 100mph.

 

Don't be quite so fast to dismiss 30 mpg! I have fitted Mesasquirt EFI to my 3.8 S Type, along with the distributorless ignition. I used carb adapters to replace the dashpot and piston of the SU with a fuel injector, otherwise the throttles/ manifold is as original.

I drove my car from Calgary Ab to Vancouver BC across the Canadian Rockies, which if you've ever driven it is a roller coaster profile of going up and down the mountains. It's ~ 1300 miles return and I averaged 29 mpg (UK gallons). I expect if I was on the flat at sea level I'd be able to achieve 30 mpg.

 

In mixed cycle use you will not achieve 30 MPG even with a system that shuts off all fuel flow on coast/zero throttle. It would be a misleading claim plus the fact that the 2.4 has to work too hard to achieve any sort of decent performance.

 

Mixed use is different of course, but the impression I got upthread was the wish was for 30mpg highway cruise economy. And that is possible.