💁 Incredible Unknown Facts About The Jaguar XK Engine | Ultimate Guide 👀

[@Anatoli50]

Some context as to how the different displacement versions of the XK engine felt to the driver in operation would be helpful. As a lifetime owner of XK’s I can share that the smaller displacement versions would rev higher, and felt more sporting, despite making less power and torque. The 3.4 liter version was the Le Mans winner. The 3.8 revved up noticeably quicker than the 4.2, and was best matched with the manual transmission. The 4.2 produced more torque and thus was the best motor to have behind an automatic transmission. The Jaguar built 4 speed full syncro gearbox available beginning in 1965 was much better driving in traffic than the hoary old Moss box introduced in 1949. The Moss box began life designed for a lorry, and was the only gearbox commercially available that could handle the prodigious torque of the 3.4 XK engine in 1949. The later GM sourced auto boxes were far better than the earlier Borg Warner units. The clutch was also improved substantially for the 1965 model year. Not mentioned is that the XK engine owes much of its longevity to the robust 7 main bearing bottom end and race car like huge oil sump capacity. The long stroke design makes more torque at lower revolutions, thus promoting engine life in normal road driving. In the 1970’s the factory production boring machinery was wearing out. This coupled with labor problems meant that tolerances and quality fell considerably for customer cars. Ford ownership has been criticized, but Ford invested heavily in modernizing Jaguar and can be credited with saving the company at a huge cost.

[@pkthorntonrestorations]

Very well pointed out, thank you!

[@classehermansson5849]

Yes and yes to all of your reply. The only thing I made a comment about was the oil pan on the engine was the newer type. The D-type version had a try sump that feed oil by a separate tank. And the XK 6 is a long bore engine, and therefore never going to rev high. Its all about torque and gears.

[@christianloepfe179]

​@@classehermansson5849Except the 2.8 litre Version needs to reved up!

[@mikejfranklin7000]

Nobody mentions that the XK engine is a hemi! I am even older than the XK engine and I only recently learned that it has so-called hemispherical combustion chambers!

[@robharding5345]

Great workmanship, those engine rebuilds are very impressive, Love all things jaguar.

[@pkthorntonrestorations]

Thank you very much!

[@paulwells4203]

You must have needed a strong drink after your customer tried to bend the tach needle on the newly rebuilt engine... Subscribed

[@pkthorntonrestorations]

Not for the faint hearted! It was all good in the end and the engine is still going strong! 💪 Thank you!

[@richradley2706]

Thank you. Very good job

[@pkthorntonrestorations]

Thank you too!

[@richardlewis5316]

I had several XJS in the 1980 which also had the V12 engine! Beautifully smooth and powerful and did about 15MPG - but worth every gallon!!

[@pkthorntonrestorations]

I know the feeling, great long distance driving engine the V12 is!

[@n1352-m1i]

so you set the valve gaps with the head off... do you occasionnally find any change in the clearance after the head is torqued down onto the block ?

[@pkthorntonrestorations]

It makes no difference, in our opinion. We always do them on the bench, recheck once in car, while the engine is cold. Hope that helps!

[@videomaniac108]

These engines are mechanical pieces of art.

[@pkthorntonrestorations]

Well said, indeed!

[@jasongarcia8996]

Hello. What solution would you suggest for a car that has all matching numbers except the head. Is there a 'M' version or something that I could substitute in absence of the original head which may have been removed because it was warped or failed. Any ideas would be amazing?

[@pkthorntonrestorations]

There’s not much you can do without the original head. Just enjoy the car! Drive it, break it, repair it, enjoy the memories

[@453vae]

Enjoyed the History here.. Have you fitted the new 123 Bluetooth distributors to any of the XK engines? JMD

[@pkthorntonrestorations]

Yes that’s what we use and they work a treat! ✔️

[@453vae]

@@pkthorntonrestorations Maybe you could do a video on the 123 distributor being fitted and setup in the future. I know alot of the MK2 Jaguar crowd are looking for this.. JMD

[@pkthorntonrestorations]

@@453vae great idea and why not! Will get it done

[@TS50ER]

That will be the XK Scorpion-Injection Model.

[@pkthorntonrestorations]

Literally! The cylinder head for our race car comes from the Scorpion tanks 🦂

[@thomasmulhall4873]

Every Abarth has a scorpion in it...at least, in spirit.

[@jharloe]

What oil would you use ? I know what the book says but oil sae has changed over time

[@pkthorntonrestorations]

Millers 20w50 👍

[@classehermansson5849]

They use the same construction of oil pan that the "new" 3.4 XJ6 engine Jaguar used from 1975 and forward, and of course the 4.2. Not slushing around oil, so the oilpump always got some oil to pic up. I have got a 3.4 from 1975 to my special build and some of the things that the engine builder proposes to his customers is for me a little bit "overselling parts"....but thats just the new world.

[@hueyhoolihan582]

too bad your shop is not over here in california, because i'm in desperate need of a rebuild (the block is cracked) on my 3.4l xk engine in my mkii. surprisingly, it managed to make it from here in california to ohio (3000 miles), including over a 12,000 foot pass in colorado, with the cracked block and a leadking head gasket.

[@pkthorntonrestorations]

They are incredible resilient engines! A well built XK engine can last over 3 decades without any major surgery. We would be happy to help, now we have a weak British pound against the US dollar 💵

[@hueyhoolihan582]

@@pkthorntonrestorations do you have a website and/or an email that i can use to contact you.?

[@pkthorntonrestorations]

@@hueyhoolihan582 yes certainly, reach out to us at [e-mail] 👍

[@thomasmulhall4873]

He is glad he is not in Ca. Ca has become a 3rd World craphole under leftist rule.

[@iamthebroker]

Hi guys, love your work. I have a 12/84 built xj6 with 4.2 xk engine. I’ve been told because my motor is Jaguar Plc engine (as opposed to Leyland ownership) the engine is much better as things reverted back to Jaguars original specs/materials used for either the heads or the blocks. I’m vague on the details but wondering if you know? Would much appreciate any info about the difference. Cheers Andrew

[@pkthorntonrestorations]

Hi Andrew, as far as we know the engines would be the same, the technology has moved on since the early days. You will probably have a big valve head which produces a heck more power than the early engines!

[@jorfedgonbol]

A Master class for Mk X owners

[@pkthorntonrestorations]

Thank you so much! 🙏

[@jharloe]

Jct or gct?

[@rogerpritchard]

My father Dennis Pritchard had a beautiful oplescent blue 1968 E-Type 1.5 series coupe 4.2cc. I can't remember the colour of the head. Would it have been gold? Thanks for the video, subscribed!

[@pkthorntonrestorations]

It would have been gold indeed! Fabulous motor cars! Thank you!

[@Philcopson]

4.2cc's??? Was it a toy?

[@pkthorntonrestorations]

@@Philcopson 4200cc or 4.2l, either or!

[@Philcopson]

@@pkthorntonrestorations Thanks, but I was only pulling Roger's leg. I was actually looking on line to see if anyone had ever posted any info, film clips etc on the 2.4 litre alloy block and 3-litre XK racing engines. Cheers, Phil

[@thomasmulhall4873]

Opalescent Blue is stunning! Enjoy

[@warrenwalker8170]

Nothing new here OF incredible unknown facts

[@gf4353]

Why does it not ever get mentioned that it is a true. HEMI engine. !!!!!

[@glennpowell3444]

You pull these engines up to power and then come off the throttle and let the gearbox turn it.They snap and snarl through the three SU carbs.Glorious.Banger racers loved them sadly.

[@pkthorntonrestorations]

Tremendous engine! So rewarding to build and enjoy ☝️

[@mrbeancounter90]

haha - Scorpion!!

[@pkthorntonrestorations]

Yup true story 🦂🇻🇪

[@Schlipperschlopper]

Sadly soon all gas cars will be banned in EU and USA! In France they have a new banning law for ICE cars called SCHLABOUBVE and in Switzerland the HESCHLAVVO law! In Scandinavian countries soon there will be a so called SMORVERBIDEN law. In Germany from 2027 the new BABVVO and TEBBVO laws by the green peoples party will bann all gas cars from public streets only exception will be professional commuter trips and state-certified transports)!!!!!!!

[@pkthorntonrestorations]

That doesn’t sound good! Let’s enjoy these cars until then.

[@jamesbrooks5442]

It won't happen too many enthusiasts

[@barrettoliver2009]

I'm so sorry to hear that , you are welcome in the UK anytime , we have existing " Historic Vehicle Exemption" so ICE passion will live on here !

[@adoreslaurel]

Lyons must have been off his meds when he came up with the 2.4 Litre, madness! reducing the capacity of this engine and turning it into a boat anchor. It could never have been a money maker and from a manufacturing costing point of view would have been his number one loser.

[@pkthorntonrestorations]

Maybe an Italian style tax saving strategic move? If cars were taxed based on cc, the 2.4l would have been in the under 2.5l class. Money in the bank! 🏦

[@adoreslaurel]

@@pkthorntonrestorations Yes, the old point 4, D squared N formula was stupid, why did they tax engines on bore diameter and number of cylinders?

[@bricology]

Nice video, but I didn't see anything that was an "incredible unknown fact". 🤷‍♂

[@pkthorntonrestorations]

Thank you, it’s all in there! 👍

[@markmathews6876]

where are the incredible unknown facts ?

[@pkthorntonrestorations]

It depends who’s watching 👀 for some viewers these are incredible unknowns facts 👍