[Rovernet] 3.5 to 3.9?

[Kent Kinard]

Geff,
A 3.5 converted to 3.9 is a better engine than a stock 3.9 if you use 
thin aftermarket sleeves instead of factory sleeves when you overbore 
the block.  The thinner sleeves leave more meat in the cylinder walls.  
Use 9.35:1 pistons.  This assumes that your 3.5 is in good shape with no 
"disappearing coolant."

I do not like big cams on the Rover V8 as the base circle of the cam is 
small.  Most cams with higher lift require stronger valve springs and 
these cause more rapid lobe wear.  If you can find a cam with near stock 
lift and more duration that will help.  The ultimate solution to cam 
problems comes if you have $2k.  That will buy you an hydraulic roller 
lifter cam from The Wedge Shop...custom ground to your specs.

Larger valves and head porting should come before a bigger cam.

The stock ignition systems on Rover V8's are uniformly bad and cease to 
function at much over 4000RPM.  An aftermarket distributor, properly 
curved and timed, and a high performance coil will really wake up the 
stock engine.  For instructions as to how to wire the aftermarket 
ballast resistor to your SD1 with Lucas 4CU injection, read the related 
info at: http://www.team.net/TR8/tr8cca/wedgelab/
NAS SD1 engine, injection and ignition are identical to  TR8.

Roverly,
Kent K.

GeffMcCarthy via Rovernet wrote:
> Thanks, Dermot.  I also have read that the SD1 breathing is restricted
> severely.  A Vitesse twin plenum was advertised a few months back, and sold
> for £800!  I plan to investigate throttle body injection on an Edelbrock
> manifold, or similar.
m