Another dyno session, 454 w bm 420 megablower
#11
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Im surprised that it kept pulling so high w stock 525sc cam, talking to eddie young he was too. Mike do you think its possible all 3 motors had bigger cams put in at one point? It wasnt neccesarily done climbing at 5900, i just didnt want to see how high it would rev before something bad happened!
#12
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Good stuff! Love seeing the 454's make some power.
its possible the engine pulled higher because of the larger blower. The 177's start giving up in the upper rpm. Most dyno pulls with them show the boost starting to drop off at higher rpm.
stock flat tappet cam is a 228/236 114lsa .530/.551. Timing event wise, IO=5 IC=43
EO=57 EC=-1
in comparison, a 500efi cam is
230/236 114lsa .598/.610
IO=6 IC=44
EC=57 EC=-1
valve timing at .050 is close.
seat durations differ a bunch though
Stock flat tappet 298/306
500 efi roller 292/298
advertises rpm range in cranes catalog
stock flat tappet 525sc cam 2800-6600rpm
500efi roller 2000-5800
roller setups are nice, but for what they cost , might make someone rethink the gains vs cost. Theres plenty of oils on the market with lots of zinc. Theres lifters with edm holes and or oiling grooves cut in the body to help prevent issues. Roller lifters these days arent without issue either.
A billet roller cam, some good lifters, beefy pushrods, easy to spend 1500 bucks or more. Where as a flat tappet can be in the 300 dollar range. Flat tappets also dont need big spring pressures to control that massive roller lifter from ski jumping over the nose . Just had this convo with a buddy who has a pair of stock 420's in his 30ft velocity Last weekend. Engines run great. Eventually he wants to refresh. Tight budget. Sounds like hes leaning towards sticking with flat tappet setups, a pair of eq or dart iron heads to replace the tired oe heads, and continuing to boat.
its possible the engine pulled higher because of the larger blower. The 177's start giving up in the upper rpm. Most dyno pulls with them show the boost starting to drop off at higher rpm.
stock flat tappet cam is a 228/236 114lsa .530/.551. Timing event wise, IO=5 IC=43
EO=57 EC=-1
in comparison, a 500efi cam is
230/236 114lsa .598/.610
IO=6 IC=44
EC=57 EC=-1
valve timing at .050 is close.
seat durations differ a bunch though
Stock flat tappet 298/306
500 efi roller 292/298
advertises rpm range in cranes catalog
stock flat tappet 525sc cam 2800-6600rpm
500efi roller 2000-5800
roller setups are nice, but for what they cost , might make someone rethink the gains vs cost. Theres plenty of oils on the market with lots of zinc. Theres lifters with edm holes and or oiling grooves cut in the body to help prevent issues. Roller lifters these days arent without issue either.
A billet roller cam, some good lifters, beefy pushrods, easy to spend 1500 bucks or more. Where as a flat tappet can be in the 300 dollar range. Flat tappets also dont need big spring pressures to control that massive roller lifter from ski jumping over the nose . Just had this convo with a buddy who has a pair of stock 420's in his 30ft velocity Last weekend. Engines run great. Eventually he wants to refresh. Tight budget. Sounds like hes leaning towards sticking with flat tappet setups, a pair of eq or dart iron heads to replace the tired oe heads, and continuing to boat.
#13
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Good stuff! Love seeing the 454's make some power.
its possible the engine pulled higher because of the larger blower. The 177's start giving up in the upper rpm. Most dyno pulls with them show the boost starting to drop off at higher rpm.
stock flat tappet cam is a 228/236 114lsa .530/.551. Timing event wise, IO=5 IC=43
EO=57 EC=-1
in comparison, a 500efi cam is
230/236 114lsa .598/.610
IO=6 IC=44
EC=57 EC=-1
valve timing at .050 is close.
seat durations differ a bunch though
Stock flat tappet 298/306
500 efi roller 292/298
advertises rpm range in cranes catalog
stock flat tappet 525sc cam 2800-6600rpm
500efi roller 2000-5800
roller setups are nice, but for what they cost , might make someone rethink the gains vs cost. Theres plenty of oils on the market with lots of zinc. Theres lifters with edm holes and or oiling grooves cut in the body to help prevent issues. Roller lifters these days arent without issue either.
A billet roller cam, some good lifters, beefy pushrods, easy to spend 1500 bucks or more. Where as a flat tappet can be in the 300 dollar range. Flat tappets also dont need big spring pressures to control that massive roller lifter from ski jumping over the nose . Just had this convo with a buddy who has a pair of stock 420's in his 30ft velocity Last weekend. Engines run great. Eventually he wants to refresh. Tight budget. Sounds like hes leaning towards sticking with flat tappet setups, a pair of eq or dart iron heads to replace the tired oe heads, and continuing to boat.
its possible the engine pulled higher because of the larger blower. The 177's start giving up in the upper rpm. Most dyno pulls with them show the boost starting to drop off at higher rpm.
stock flat tappet cam is a 228/236 114lsa .530/.551. Timing event wise, IO=5 IC=43
EO=57 EC=-1
in comparison, a 500efi cam is
230/236 114lsa .598/.610
IO=6 IC=44
EC=57 EC=-1
valve timing at .050 is close.
seat durations differ a bunch though
Stock flat tappet 298/306
500 efi roller 292/298
advertises rpm range in cranes catalog
stock flat tappet 525sc cam 2800-6600rpm
500efi roller 2000-5800
roller setups are nice, but for what they cost , might make someone rethink the gains vs cost. Theres plenty of oils on the market with lots of zinc. Theres lifters with edm holes and or oiling grooves cut in the body to help prevent issues. Roller lifters these days arent without issue either.
A billet roller cam, some good lifters, beefy pushrods, easy to spend 1500 bucks or more. Where as a flat tappet can be in the 300 dollar range. Flat tappets also dont need big spring pressures to control that massive roller lifter from ski jumping over the nose . Just had this convo with a buddy who has a pair of stock 420's in his 30ft velocity Last weekend. Engines run great. Eventually he wants to refresh. Tight budget. Sounds like hes leaning towards sticking with flat tappet setups, a pair of eq or dart iron heads to replace the tired oe heads, and continuing to boat.
#16
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Im running a 236/245 114 LSA hyd roller, seat duration is slightly less than the stock 525sc flat tappet. Installed at 110icl, power was still climbing at 6200, but fizzling off. Next dyno session, installed on 114 icl, pulled to 6500rpm, never saw it nose over