Job # 2189 (MW) - Stage Two 7 liter Jaguar V12
Stoker engine rebuild incorporating very special Group 44 cylinder heads



Update report - November 5, 2017

Corey has been busy porting the intake manifolds for this special engine. The factory manifold has to be sectioned, effectively cut in two, in order to access the runners to port them.



Cutting away throttle body panel to allow access
to the intake runners inside the manifold
Prior to porting










After porting
Comparing ported and 'unported' manifolds




I am pleased to report that we are getting very close to wrapping up this special Stage Two 7 liter rebuild.



Cylinder heads now installed




























We have now fully assembled the cylinder heads and should be wrapping up this build next week.



100% custom valve train, designed and
manufactured just for this build
Heads now fully assembled




It is always fun when we are given a blank canvas and told to design and build an engine without compromise. The following sequence of photographs show the design and creation of a set of custom forged pistons for this special build.




Making a piston mold and marking
valve position
First a dish was machined in the piston top










Machining huge valve reliefs
From plastic mold, to blueprint, to finished article











Debris found inside the stroker crankshaft










Next task is to define and establish rod
side clearances











Machining new rods in order to achieve
desired side clearances























Cutting and installing the piston rings
Time to get the short block assembly underway










Note one piece RBR rear seal












Rods hung on pistons










Piston and rod assemblies installed











Installing the new oil pump












Timing chain assembly installed






















Oil pick-up plumbing assembled












Trial fitting external oil cooler and pipes









To be continued!





Block machine work, continued...



Indicating additional relief that will be needed
for full honing stroke
Block now machined for over-sized custom liners




Boring the block to accept the custom over-sized liners.



Custom oversized liners
Boring the block for the new liners









To be continued..
Factory bores were .002" out of round




Comparing the Group 44 heads to more traditional Jaguar castings has thrown up some remarkable flow test results. At about .450" lift, a standard V12 Jaguar intake port flows around 159 cfm. After our Stage One/Two porting and valve job, the standard V12 Jaguar intake port will pick up around 37 cfm, ultimately flowing about 197 cfm.

The Group 44 heads, with their completely different casting and runner design, plus of course larger valves, flowed an impressive 235 cfm right out of the box. Following our valve job, and blending the seats to the venturis, we picked up an additional 15 cfm, for a maximum flow number of almost 250 cfm - more than 90 cfm more than an unported V12 Jaguar intake typically flows.

These numbers are pretty spectacular!



Note difference between Group 44 ports (lower) and
the regular Jaguar fayre (above)
Surfacing the heads






















Blending valve job with venturis











Designing custom stroker piston by creating
a plastic model
This is a sample of typical Stage One/Two V12 flow
numbers (before and after porting)










Out of the box, the Group 44 heads flowed 38 cfm
more than even our ported standard Jaguar casting
After CJ valve job and venturi blend, the Group 44
heads flowed 106 cfm (@.500 lift) more than a
standard (unported) Jaguar casting!




I am pleased to report that we now have this very special engine rebuild well underway.

















Pulling seized cylinder heads using our special tool






















Group 44 heads will be used in this build. More
on this later...
Pressure testing the Group 44 heads










Preparing to bore out the block for the custom
over sized liners
Align hone in progress











Stroked forged crankshaft











Lightweight billet steel flywheel and special
RBR rear seal upgrade

Go to other CJ engine rebuilds