Jag V-12 Engine
- FRANK BASILE
- Old Hand
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Re: Jag V-12 Engine
I have a feeling that the box behind the V12 was more akin to an FMX .
OZ-E-Rodders Rod and Kustom Club Member #31
- fredeuce
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Re: Jag V-12 Engine
Frank , all SIII V12 Jags had the Turbo 400.FRANK BASILE wrote:I have a feeling that the box behind the V12 was more akin to an FMX .
The SII is where you can find both the Turbo 400 and the Borg Warner 12 boxes.
Cheers, Fred
fredeuce
- FRANK BASILE
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Re: Jag V-12 Engine
Thanks Fred . I had pre S111 .
Frank.
Frank.
OZ-E-Rodders Rod and Kustom Club Member #31
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Re: Jag V-12 Engine
Correct me if I'm wrong, but I understood the jag 6 was heaver than a sbc or sbf, marked it's territory (like most pommy engines did) & wasn't renowned for economy.
I knew a bloke who owned a transport business. He put a sbc in one & assured me that it was gutsier, (is that how you spell "had more guts"?) handled better and was more economical. (Gotta say it sounded better too!).... oh, and he could park it in the driveway without a tray under it

...... Not that jag 6's have anything to do with the original question....
I knew a bloke who owned a transport business. He put a sbc in one & assured me that it was gutsier, (is that how you spell "had more guts"?) handled better and was more economical. (Gotta say it sounded better too!).... oh, and he could park it in the driveway without a tray under it


...... Not that jag 6's have anything to do with the original question....

- steve the ford guy
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Re: Jag V-12 Engine
Im only a novice on jags, but just about every jag sedan that friends and acquaintances have had were fitted with 350 sbc motors, except for the odd one out that had a 308 Holden, I have a former friend in the local area, he has two jags, both have sbc's. If someone told me sbc's were a factory option I would believe it. 

- torana68
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Re: Jag V-12 Engine
it was the high performance optionsteve the ford guy wrote:......................... If someone told me sbc's were a factory option I would believe it.
wanted : chrome reverse 15" Ford pattern
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Re: Jag V-12 Engine
torana68 wrote:it was the high performance optionsteve the ford guy wrote:......................... If someone told me sbc's were a factory option I would believe it.










I've got a mate who's getting a v12 restored. I'l show him that post. Should get him going



- fredeuce
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Re: Jag V-12 Engine
That's right. When those conversions were done the front ends would sit considerably higher than with the Jag 6 and so the springs need to be changed or lowered to get the ride height the same. The 2.8 litre versions (compared with the 4.2)are a lighter engine with lighter springs and don't need this change.MickD wrote:Correct me if I'm wrong, but I understood the jag 6 was heaver than a sbc or sbf, marked it's territory (like most pommy engines did) & wasn't renowned for economy.
On my SI with SBC some years ago now on a steady trip to Melbourne with Holley 650 spread bore and 2.88:1 final drive I achieved 23 mpg. I don't think the 4.2 XJ6 ever got close to that.
fredeuce
- steve the ford guy
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Re: Jag V-12 Engine
Ask him if the v12 bolts straight up to his jags sbc mounts.MickD wrote:torana68 wrote:it was the high performance optionsteve the ford guy wrote:......................... If someone told me sbc's were a factory option I would believe it.![]()
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I've got a mate who's getting a v12 restored. I'l show him that post. Should get him going![]()
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- Whippet2
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Re: Jag V-12 Engine
back in the late '90's Peter Reeves from geelong built a speedway super sedan using the jag V12 i remember he bored it out and used holden 202? pistons it made over 500hp but only ran for a few seasons before a road accident ended his racing (head injury), i beleive the car still sits in a shed somewhere in Geelong.
- fredeuce
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Re: Jag V-12 Engine
That's interesting. A mate of mine who lives at Drysdale in around year 2000 had a XJS v12 he picked up that he thought was being set up as a sports sedan for circuit racing. From memory this was equipped with a Ford toploader and 9" rear. Don't know what happened to that one.Whippet2 wrote:back in the late '90's Peter Reeves from geelong built a speedway super sedan using the jag V12 i remember he bored it out and used holden 202? pistons it made over 500hp but only ran for a few seasons before a road accident ended his racing (head injury), i beleive the car still sits in a shed somewhere in Geelong.
fredeuce
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Re: Jag V-12 Engine
Whippet2, fredeuce.. might this be the Geelong car Peter Reeves built.. full tubular chassis with a Winters quick-change rear-end, Willwood brakes etc.. the main feature of this XJS is up front.. A 5.3 pre HE V12 drinking methanol via S.U.’s and fitted with a dry sump conversion.. The owner advised me that car has dyno sheets evidencing over 500hp. The other two images, kindly provided by Reg Lee, is of course, the Utting & Lee T-Altered from South Aus.. that later ran in HE form as a Rail





'36, or is it ?, Ford pickup ( one day..) an' a 'A' hangin' in the rafters ( or was.. the rope broke )
- Whippet2
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Re: Jag V-12 Engine
yep thats the speedway car i was talking about, my uncle used to pit crew for him and assisted in the building of the car.
- turns
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Re: Jag V-12 Engine
I drove an XJ6 as a daily for 5 odd years. I didn't live with the 4.2 for very long. I gave it the floatation test and fitted a 350 Chev and was shocked by the weight difference to be honest. The Chev donk sure livened things up and made the whole car better to drive (after the height adjustment). The car hauled arse with the Chev in it and was diabolical in the wetMickD wrote:Correct me if I'm wrong, but I understood the jag 6 was heaver than a sbc or sbf, marked it's territory (like most pommy engines did) & wasn't renowned for economy.
I knew a bloke who owned a transport business. He put a sbc in one & assured me that it was gutsier, (is that how you spell "had more guts"?) handled better and was more economical. (Gotta say it sounded better too!).... oh, and he could park it in the driveway without a tray under it![]()
...... Not that jag 6's have anything to do with the original question....

As an aside, I drove an HG Brougham for years prior to that. Both of these model cars offer good parts for hot rodders especially the front suspension set ups. There are obvious track width differences but many people over estimate the weight difference between the HKTG and XJ Jags. My Jag weighed in at 1700kg prior to the engine swap from memory which is less than my current Commodore. The Brougham was a similar weight (a bit less). Just my experience, do your own math for what works.............
The pics of the V12 in mgyxjc's Jag is super neat and car porn in my opinion

There was a Holden panel van years ago owned by John Strachan (he owned the Chrome Exchange at Arncliffe) that had a Jag v12 and running gear - called Alley Cat.
Cheers Turns
"Normal is an illusion. What is normal for the spider is chaos for the fly"...............Morticia Addams
- angliadon
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Re: Jag V-12 Engine
Alley Cat still lives, the restoration is nearly complete and it was at the Van In at Hervey Bay last month. Still running the V12 but now with Injection instead of the 6 SUs.
Angliadon Member OZERODDERS President Northern District Rod & Custom Brisbane. QLD ASRF State Secretary.