Page 1 of 1
P38 4.0 Cam Lift
Posted: Fri Apr 04, 2008 3:55 pm
by TVRleigh
anyone know the spec of the standard x-bolted 4.0 LR P38 Serp Cam sharft.
Thanks
Leigh
Posted: Fri Apr 04, 2008 6:43 pm
by russell_ram
Yep,
RV8 4.0L
32/73/70/35 IVO/IVC/EVO/EVC 9.94mm lift @ valve.
fyi 4.6L
12/72/62/22 and 10.57mm lift.
Russ
Posted: Fri Apr 04, 2008 7:05 pm
by ChrisJC
So what would happen if you stuck a 4.6 litre cam in a 4.0 engine (or vice versa)?
Chris.
Posted: Fri Apr 04, 2008 7:59 pm
by CastleMGBV8
The 4.0 cam would appear to have livelier timing but has very little lift @ .391"
the 4.6 is softer and designed for torque which explains why it only produces 220BHP in standard High compression spec.
Leigh if your looking to get close to 230BHP I'd stick with the 4.0 cam and do a little work on the heads,
Suggest openening out the throats behind the valves to seat size as essential, bullet the guides and port match the ports and inlet to gasket size, you should already have waisted stem valves. Mill 20thou off the heads to give approx 9.75/1 and this should give you close to 230BHP.
Kevin.