My rods are still on the table.

Not enough time

 

Looking at the build page on the ClassicJag page makes me wonder if they're doing test fits. Clearly they're going for horsepower, but as XJR5006 pointed out in another thread, the main caps have weak spots that need to be addressed in high HP applications to prevent them from cracking, and the little stress risers near the center nuts on the main caps clearly haven't been smoothed over in the pictures.

 

also there is a difference between caps of 1st photos and the second engine photo!

1st one are BL (British Leyland), second pic could be custom material No markings!

i know that Grp 44 went to machined STEEL on later engines!

back in 1964 i worked for GE (General Electric Vietnam era), lot of special war materials and one of the Tool&die guys made a set of Berriliam main caps for me!

Chevy V8 gold color! often wonder where they are today?? probably scrape, nobody knew what thet were!

 

Def a difference, and from all accounts the OEM material is simply Chilled Grey Cast Iron for rigidity/low expansion... (but susceptible to fracture).

I can't say for sure, but I wonder if those caps were made just during the British Leyland years.

A quick google search looking for the V12 bottom end shows 2-3 different (OEM I think) caps.

BL Logo caps:
http://classicjaguar.com/cj/7917mw12.jpg
http://classicjaguar.com/cj/121016mw10.jpg

Non-logo-ed caps.
stage2v12

Best Engine Oil ? XJ12C

Solid looking later 94 engine caps:
6.0 V12 Engine (race) » Tom Mackie Racing

If these ARE all OEM caps, #1, why the differences? #2, are the 94' caps better?, #3 why hasn't classicjag addressed the issue on the example HiPo engine.

 

Never seen those main caps

 

those look good, most likely steel , and lighter weight than factory!

 

Great work, I smell the work of the 'Man from Melbourne'........NA Lutz. a great engineer, best, JW

 

My 6.7L is being built by Norm, and what I have done was with his guidance.

 

warrjon ,are you using custom main caps??

 

No stock main caps, I talked to Norm about it and he used stock main caps on all his HIPO V12's most of which made 600+hp

 

This is awesome.

Are you keeping the transmission stock?

I have an 89 XJS and am getting ideas on what I can do. I never looked into it that much. I am sure a lot of work is custom because not a lot of XJS owners are modifying the engines ( well at least I thought that before I joined the forums, ha)

 

I already have a 4L60e installed behind the 5.3L with 3.58 rear gears. I'm lucky I have the guidance of Mr Lutz as I head down the big V12 route.

 

If you decide you would like to add a transmission that provides more "grunt" at the lower end and a 4th. speed Overdrive, I have a kit that allows for the installation of the 700R4 transmission (mechanical shift as u have now...no need for the coax cable as in the later4L60e)...requires the shortening of the drive shaft and rebalancing. The 2:88 provides plenty of speed and grunt without changing the differential gears. Call if you are interested at 559-313-5410, Best, JW

 

Classic Jag finished up their reshaped HE heads. I don’t know much about the shape, what do people think?


2240

 

Very similar what I did to my chambers, except RH side of the intake valve seat, that looks very thin in the casting

 

.

NICE work, excellent! should run withe best!

altho just an opinion, seems both valves are slightly shrouded, relative to Pre-HE/flat chamber!
plus many chambers have the sparkplug facing the inlet valve, so as to cool the electrodes.

ron