Fordy
05-05-2016, 21:03
So 4 years ago i built my engine and its undergoing a major rebuild, the more a strip the more i find worn or damaged,
Crank pitted on main journals,
1x Conrod bent
3x Inlet valve collets cracked in half and valve grooves elongated
Oil pump scored beyond believe was a refurb unit 4 years ago
8x Cam followers pitted
Camshaft pitted on lobes was reprofiled 4 years ago by piper 285
So my rebuild so far includes
New crank
Forged 77m wossner pistons, pec rods
Ductile liners
Head modified bigger inlet 36mm and exhaust valves 32mm, 3 angle seats yada yada, head skimmed to 73mm
Head CC'd at 41.5cc
Compression ratio atm up around 8:5-1 (Megasquirt fitted so not worried)
But with finding my cam pitted, I wonder if the 285 is really needed anymore?
Looking through as much as i can wouldn't a 5500327 BB cam be better suited?
My thoughts are, Bigger valves require less lift for same flow and I noticed the higher I rev'd up to 8000rpm at times the more often push rods got bent, got to admit flat shift was being used so probably didn't help :smokin: kinder lobe ramp rates happier valvetrain
SO
CatCam "BB" 5500327 OR Piper 285 blank?
Crank pitted on main journals,
1x Conrod bent
3x Inlet valve collets cracked in half and valve grooves elongated
Oil pump scored beyond believe was a refurb unit 4 years ago
8x Cam followers pitted
Camshaft pitted on lobes was reprofiled 4 years ago by piper 285
So my rebuild so far includes
New crank
Forged 77m wossner pistons, pec rods
Ductile liners
Head modified bigger inlet 36mm and exhaust valves 32mm, 3 angle seats yada yada, head skimmed to 73mm
Head CC'd at 41.5cc
Compression ratio atm up around 8:5-1 (Megasquirt fitted so not worried)
But with finding my cam pitted, I wonder if the 285 is really needed anymore?
Looking through as much as i can wouldn't a 5500327 BB cam be better suited?
My thoughts are, Bigger valves require less lift for same flow and I noticed the higher I rev'd up to 8000rpm at times the more often push rods got bent, got to admit flat shift was being used so probably didn't help :smokin: kinder lobe ramp rates happier valvetrain
SO
CatCam "BB" 5500327 OR Piper 285 blank?