Holley Sniper EFI + HyperSpark (my way) in pictures in 1969-70 Technical Forum Posted May 11, 2020 · Report reply When we first installed it, it ran great for a couple of weeks.. then the 02 Sensor went out and i provided photo's to holley showing the 02 installation .. then Holley shipped me a new 02 sensor and it was running great... felt like a different power band especially up in the RPM. well i took her out one day just one more rip before i pull the Mallory MaxFire distributor and replace it with the HyperSpark setup.... and so ... once in a while ill hit the rev limiter and shift ... well it pulled very strong all the way beyond 8K... i shifted.. wholly crap that was a rush ... sun was going down pulled in the driveway ... and turned to park and notice a bit of smoke passing across the hood... yep no rev limiter... not sure what happened but the MaxFire seems to have lost its settings.. i guess ill pull her apart and see whats up when i have time... i run Evans coolant so it didn't look like oil or coolant burning.. and did not smell like oil burning or coolant etc. probably just a head gasket... everything internal is forged, H-Beam rods, internal balanced etc. i pulled the valve covers and checked the rockers and push rods, nothing is broken or loose up top...no unusual noises.. no smoke until it warms up a bit to temp.. then a slight coloration. another days project.... good times :-) sniper was one of the best investments i have made to my build. all that to say... i was planning on tuning after the Hyperspark ... so not yet.