I need some help :headscratch: , I have a set of Comp Cams stage 2 grind number XE270AH PART # 102600. Lift is .55 Intake & .55 Exhaust , duration Intake 234 Exhaust 238
My question is if this cams are used on a 5.4 Lightning motor does the Piston will need notch for valve relief? my first though is no because piston on 5.4 sits lower :tu compare to its little brother 4.6 :scared1:
I'm asking this because I bought a Ford Lightning GEN 2 with a MMR 1000 engine with bad motor (previous owner though cracked block). when a took apart engine I found the problem (the 2 freeze plugs inside the timing chain cover were popped out) so engine is on process of being rebuilt.
Engine does have the Manley rotating assembly with spherical dish piston -18 cc
I notice when I remove engine heads I notice a slight marks on piston & valves :headscratch: like they hit each other (a very slight marks) on one side they look like intake valves were hitting and on the other side the exhaust valves were hitting.
It seems to me that the timing was not set right or the chain stretched or the chain main tensioners failed or all of the above.
I called MMR and they told me that those cams will fit with those pistons and that 5.4 can take cams with aggressive lift compare to 4.6 because piston sits lower in the hole....
Have any one have or know about the issue? please advice , have plans to put back same cams.. :scared1: when engine is ready..
My question is if this cams are used on a 5.4 Lightning motor does the Piston will need notch for valve relief? my first though is no because piston on 5.4 sits lower :tu compare to its little brother 4.6 :scared1:
I'm asking this because I bought a Ford Lightning GEN 2 with a MMR 1000 engine with bad motor (previous owner though cracked block). when a took apart engine I found the problem (the 2 freeze plugs inside the timing chain cover were popped out) so engine is on process of being rebuilt.
Engine does have the Manley rotating assembly with spherical dish piston -18 cc
I notice when I remove engine heads I notice a slight marks on piston & valves :headscratch: like they hit each other (a very slight marks) on one side they look like intake valves were hitting and on the other side the exhaust valves were hitting.
It seems to me that the timing was not set right or the chain stretched or the chain main tensioners failed or all of the above.
I called MMR and they told me that those cams will fit with those pistons and that 5.4 can take cams with aggressive lift compare to 4.6 because piston sits lower in the hole....
Have any one have or know about the issue? please advice , have plans to put back same cams.. :scared1: when engine is ready..
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