Jag V12

Hi Guys
I am thinking of building a kitcar and putting a 5.3 HE jag V12 in it. Seen one I like, but... and its a big but... Does anyone know how long the V12 is, I know it weighs 300kg but I have to get it in the back of a Ford focus

 

indeed.
Can't help you with the dimensions, but this I gotta see. Nick please post updates if this project gets off the ground.

P.S. If the Jag V12 is too long, how about a small block V8?

 

I don't want to do a V8, already got one of those in the GT4 I am just googling jag V12, and it looks like they are about 34" long and a 3rd of a tonne.

 

Go with the Jag 12, make everything possible to fit the engine, it would be wayy cool to have that engine. If properly tuned they run great, and if you fit some nice headers and Webers it is a monster.

 

I think it will fit in the back of the Focus but how will you lift it in and out?

 

forget building one with a jag 5.3 V12 yourself, and buy this:-http://www.carandclassic.co.uk/car/C25240 and it comes with a spare engine.

The size you need is 36 inch long 34 wide and 34 high,[ without gear box, it can be made smaller by takeing off the air cleaners and pullys] they are very heavy [ 4 man lift] , i used a small trailer and lifted in on with an engine hoist one end and a JCB the other. what is the kit you are thinking of?
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Fork lift truck his end, gravity mine I guess, probably make a ramp and slide it out attached to a block and tackle.

Dunno yet, saw the lump and am buying it, figure out what to put it in next. I fancy building some kind of space framed chassis mid engined thing. Next I need to source a gearbox/tranny unit I can mate up to the V12, Once I have all the bits I can work on where I can put it all.

 

My car above came with a BMW 5 speed manual, if you need advice, i can give you the name of a good jag man in Surrey near you. If you want to have a look at my car you could bring your aircon unit, i would have it, if a deal can be done, just did not fancy the trip down to you.

 

I am in two minds about selling the aircon, I put it on ebay then pulled the advert, something tells me I should keep it with the car.
As regards the gearbox.. If the engine is in the middle the gearbox/back axle have got to be in one lump, a bit like the Gt4s, but not transverse.

 

Nick
keep the air con unit with the car, if you have to sell it you can bet your life the first question would be "do you have the air con that came with the car", i only wanted it as a spare, spare.
Good luck with the project and if i can be of help just shout.
Grant

 

Hi Grant
I now have my V12, its huge!!
However, i need to convert it to a manual flywheel. do you know whether the flywheels on straight six's and interchangable with the V12's?
My fly wheel is 345mm in diameter and has 12 bolt holes in the middle 92mm pcd

Also if anyone can help with the engine type..
number 8S 16503 HA

Any help would be awesome!
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You'll need a flywheel from a Series 3 Etype.

This is the LEAST of your problems.

 

and an inverted porsche transaxle if your going mid engined.

was a keen kit car person in my youth - you are about to climb a mountain - check you oxygen supply, altitude does funny things to the brain, before you know it you'll be saying "how hard can it be"...

 

Go on then Tim, whats the biggest problem?
I am going to build a spaceframe chassis, mount the V12 in the middle coupled to either a Renault UN1 or Audi/VW transaxle via an adapter plate. Running gear will hopefully be mk3 Granada.

 

Hi Nick
it's an HE engine looking at the fuel injection rail, it should have small spark plugs [ they are a nightmare to change as the thread seizes up as they don't get change often enough as they are hard to get at.
try Peter Godwin about the fly wheel [ he an ex. Lister jag mech] tel.01306 713399
Good luck with it and keep us informed.
Grant

 

I'll start by saying that I work on 12 cylinder Jags and own one.

Considering size and weight it is very underpowered, prone to overheating and leaks and very expensive to rebuild. The result is a not really attractive engine (compared to other V12's) that has a pretty unimpressive sound.

Unless you know the history of the engine you bought, expect to spend a lot to get it right.

The intake system is pretty restrictive and is a lot of the reason for the poor performance. I would throw it out and go with downdraft Webers if you can afford the cost and increased height.

I once dreamed of a project like you are describing and I assembled many of the components (including the Webers and manifolds). After a while the insanity passed.

Good Luck, if you go forward I hope you'll document it and keep us informed.

 

Hi Grant
It has standard plugs , N9YC - Unipart GSP4362 plugs, I pulled them out to see how it last ran, and everyone looks OK, the oil is clean, and it turns over, albeit you can feel loads of compression - and thats without oily bores.
The motor had only done 70k miles, so not a lot for a big lump like this.I checked the only resource I could find and it seemed to suggest that this engine is a early pre HE block (the 8s in the engine number?)

Thanks for the tip re flywheel. I will post a blog somewhere when i ger started. This weekend i am starting by making a 10th scale model so i can mount the V12 and check for stresses etc..
Cheers
Nick

I have always wanted to make a car from scratch, so now's the chance - the regs around registration are pretty tough now, everything has to be TIG welded, and made from CDS tube. I am also going to cast my own body, the idea to make something that resembles a ZONDA C12. I was thinking of doing a Lambo, but there are too many of them around

I have drawn rough plans for the chassis, will hoefully order up some bits of steel next week (subject to wife permitting).

 

The early engines are prone to dropped valve seats (from overheating), have low compression ratios (cylinder heads are flat, combustion chambers are in dished piston tops.

 

I was told that the pre HE engines are the best for tuning, due to the flat cylinder head?

 

Not sure why that would be so.

 

Nick i was told the same about tuning. Are you sure that's your eng. no.[ above the fly wheel] they usually start 7p. what size socket fits the plugs?
that's defo. a HE fuel rail that your engine has got, pre HE had round rails not square.

are you planning on going the fuel inj. route? this is very complicated, if you are i would recommend you buy a whole donor car,so you can use all the ancillaries, wiring loom, ecu etc. , i bought a 26,000 mile car [ disable driver's car]for under £1000 used all the parts i need and sold the rest on e-bay. its fantastic to have a whole car, if you need a spring, grommet, fuel pump whatever it's just there.
If it was me though, i would go the 6 Weber route, As 2NA said, much simpler, better looking and better sound, the down side is a kit for a V12 is about £3000

 

Hi Grant
Yep, that the engine number.
The plugs are standard n9ys, with the standard socket size (same as my GT4). The distributor is an early lucas opus with the ceramic disk (same as mk3 etype?)
Maybe the rail has been transplanted at some time?
Started designing the chassis today, 1/5 scale using wood so far when scaled up I will need 30 odd metres of the stuff for teh whole car, and I still have a bit to go. But it looks quite rigid.
The pattern I am using is below. I intend to modify this design to fit the V12 Renault UN1 transaxle and mk3 Granda running gear, I have a freind in the metal business who can get me the CDS for the chassis but I will hve to upgrade my MIG to a TIG so I am told.

I like the idea of a donor V12 jag, there have been a few wrecks selling on ebay recently - eyes always open!
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I haven't been idle, I have spent the last few weeks collecting bits to make a car. Yesterday I picked up the Audi transaxle and all the ECUs to get the engine running. I have also been stripping down the V12 and getting 30 years of dirt off the various bits.
Today I made the gearbox adapter plate template out of 13mm MDF, it all fits togther quite well. I need to get an Audi flywheel and clutch though. I also need to get the Audi/VW starter motor to fit, so there will be some work there to modify the V12, should be OK though.
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hi Nick
Great to see it's coming along nicely.

see if you can get a gear reduction high touque starter, they are much smaller and it could be a big ask for a standard VW group one to turn over the V12 fast enough [ you might try the British starter comp.] they sell the for most cars inc. Ferrari, good luck with making it all fit, you are a much braver man than me.

 

Such a facinating thread. Please keep us updated! It would be cool to see it to its end result.