The 92mm crank is from EN40B Billet; the forgings wont do that kind of stroke. If you check the pics in my garage you will see the manufactures sheets; Firm was DKE in the UK shortly after to become Arrow Precision. They dont get much better than that. If you contact them it would cost you well over £4K now from them.
The bungs are the blanking off of the oil ways in the same way that the XK cranks have them. This allows for superior oil flow with cross drilling.

 

xjr5006, where do you race the XJR5?

and what class(if any)?

will you and team make it to USA for some races?

we got some awesome tracks ,like Daytona in late Jan/Feb vintage stuff!

i'm now in Austin TX where the new F1 track is now open. they have races for many types of cars.

Circuit Of the Americas,(COTA).

 

I have raced XJR5 #006 all around Europe since 2000 in Group C revival races. Lots on pics on the net usually as 40 or 140. This is the Miami GP winner. If you are willing to look you will find pics a way back on the Group 44 site on FB. Lovely car but now is giving away too many years too much weight and power to the turbo cars like the Merc.
We actually race these cars as they were meant to be raced, maybe harder, with no quarter given and none expected. I can promise you that to beat soe of the later cars I have had to drive the wheels of the old girl more happy than I became happy with of late.
Hoping to put out an XJR12 soon, 150Kgs lighter 150 BHP more power + more advanced suspension, aero etc etc.

 

Another new bit made for the engine:-

Valley plate to delete the dizzy and locate the coil packs.













Looks like a real nice bit of kit to me.

 

As a newcomer to this forum (my jag interest has been on idle for some time) I remeber a guy who was active on Jag-lovers.org. He installed 2 Whipple/Lysholm twin screw blowers on his pre-HE headed engine. That mill for sure made over 500 hp's.

Sorry if old news, I didn't look through all 20+ pages of this thread

 

not to be facetious, but that valley plate and ignition system propbably cost more than my whole car!

but never the less absolutely beautiful.

 

merc-man ,OP was reffering to N/A Jag V12s.

i'm sure a properly done forced induction engine could make 500 or more!

 

Quad turbo forced...

http://www.benzboost.com/attachment....6&d=1357219372

http://www.turbocare.co.nz/jaguar-v1...rbo/#more-1898

 

care to estimate the cost of that level modifications??

$100K or more,just engine,not whole car.

 

Nice new TWR head castings, Project 800BHP+ & 10,000RPM is on track, well it will be when finished, lol

 

great pix, please keep us up to date (at your conveinence ) with the machining processes! thanks again.
ron

 

love the cam covers

 

i like how the exhaust ports are raised higher and shaped for better flow!

be nice to see a Grp 44 head is done in comparision to TWR head.

the last of 44 competition cars was 1987(hauler driver would stop by my shop) to show more of the car in trailer,Daytona FL.
did your team have the molds from the 80s, or did you have new ones made,possibly with more R&D into them?
at a recent interview with Bob Tullious he mentioned his heads were cast and machined in California, I wonder were those molds are now!
anyhow lookin good.

 

Just a teaser pictures of the first side of the headers I'm making

 

So very very difficult to get equal length primaries squeezed in a standard engine bay.
But when the inlets are not equal does it matter for the exhaust? Maybe a spread of power is also preferable to peaky power too. Just getting rid of the cast iron exhausts will release 30-50 horses.

 

Will yours go in the standard engine bay?

and how much is it costing you to produce them?

they look good by the way!

 

Having the luxury of Gp 44 CA heads (I guess more than anyone else) and now the late TWR heads to put side by side with modded 7L Lister heads I come to the following conclusions:-

The Group 44 heads are the nicest castings but were designed for the best flow from the 6L engines running 1.8 inlet valves. They can be hogged out a bit more to take 1.9 in the 7L versions (I have never come across a genuine 6.5L to know exactly what was in there.) There isnt really enough 'meat' in the castings to go much bigger on the porting.

The TWR castings have larger exhaust ports from the foundry and are designed with 7L in mind and even the 7.4L late engines. More machining work required as the castings aren't as fine in detail in many areas. There is clearly enough metal in the ports to make much larger ports for improved flowing on the larger 7L + engines. I find that the CA heads tend to run out puff at 7.5K even with aggressive camming and timing.

The Lister heads are well worked and have huge ports compared to Std but they just are not in the same league are the 'real deal'. Because the ports are relatively unfinished from the factory the costs of doing a nice porting job to get to the Lister standard and size is very high; there is also a risk of going through and junking the lot if you are not careful. Even with such care you could be a little unlucky and get a head with a touch of core shift! Been there, not good.

Couple of pics of the raw castings exhaust ports; note the dimensions (& remember this is before opening out and flowing) Then measure your own!

 

thanks again, looking good anyway!

just maybe when some ports are finished you can post pix, with a light bulb shining thru.

both inlet&exhaust, i have always been interested in engine air flow knowledge, i know there is more to it than cyl. heads,but it seems as tho they are the major link to power,(as always).

Ron

 

The Jag V12 is so very simple, The head is flat, the pistons work out themselves so the heads and cams are everything. I say the pistons work themselves out as when you are after serious power the cams dictate cut out depth in the pistons & the valves dictate the diameter, you need a cut by the plug and if the comp ratio is a tad too high you can have a further central bowl to lower it. Nothing more can be done. Certainly on a reasonably radical engine the valve cuts are so large and deep that little more is necessary to get the correct comp ratio. The top uncut part of the piston is at or about at the top of the bore to max squeeze.
On engines with cometic gaskets I run a piston height of +025-030 ie above the liner top. The assembled height of the gasket is (from memory) .053 so giving a clearance of appx 25 thou.
Cam timing is everything, the timing is advanced from std and I have taken 4 hours on occasions getting it correct to 0.5 of a degree on both A and B banks. I use a huge disc attached to the 7.25 clutch ring. The A is advanced 0.5 to 0.75 to the B; bit like a 427 cammer.

 

427 cammer Ford engine ,we are lucky to just see one here in the states, very rare engine!
Ford beat Ferrari at Le Mans, 427 FE side oiler. He was satisfied and race programs slowed down, along with expensive developments! woulda,shoulda,coulda!
Can-Am was coming on strong, and that cammer would have been a great contender, but ford never liked just a USA series, he wanted the world series.

1st cammer i seen was around 1967, in racer Pete Robinson rail dragster supercharged NITRO car. it was fast (cant remember much).
2nd was in Massachusetts Ford car dealer,late 67, talk was there was a 1967 Shelby Cobra, with a 427 cammer in it, drove 50miles, and there it was on the show room floor in all its glory! sales rep said it was a special order vehicle.