Meep-Meep
дворянин
Yesterday a young lady brings me a hurt 440 out of her expensive 70 resto mod Charger that she recently purchased. The engine has under 400 miles and suffered some major damage because whoever built it missed the mark on the details. One clearly missed detail is a rocker arm spacer on the other bank was in the wrong position.
Why do people run those crappy stock rocker arms and 5/16" push rods in anything but a stock cammed engine!?! Dual springs with high open pressures have no business under those rockers arms. Making rocker arm skewers with push rods should be a clue that those rockers are not up for the job when high spring pressures are used.
Also note a major factor in this failure was the retainer hitting the rocker. Hard to see here but the edges of the retainers where contact was made is present on most of them. She thinks the failure was her fault by taking it to 6000 RPM but it's not. A valve train that is substandard will become a secondary spring and tend to flex in unpredictable ways as RPM increases. Really bad things can happen at 6000 RPM and one must design accordingly.
After pulling the heads the news only got worse. Crack in #8 cylinder, the intake valve seat from #8 found its way in three other cylinders. A small hole in #3 piston. Initially I thought the failure was caused by the high RPM and the retainer hitting the inside of the rocker, possibly dislodging the keeper. While that is not impossible, the failure may have originated by the intake seat falling out. Anyone have any similar experience with 440 Source heads? Seats falling out that is. I have no idea what cam is in it but it has dual springs and it's a hydraulic flat tappet.
It's now my task to bring this back to life and make sure it can handle 6000 RPM under the foot of this young lady, who also has a Porsche 911S turbo. When I suggested this may have a hot cam and I can tame it down she says "oh, I don't want to loose that." Haha! OK fine with me. This thing will be Brandi proof!
Why do people run those crappy stock rocker arms and 5/16" push rods in anything but a stock cammed engine!?! Dual springs with high open pressures have no business under those rockers arms. Making rocker arm skewers with push rods should be a clue that those rockers are not up for the job when high spring pressures are used.
Also note a major factor in this failure was the retainer hitting the rocker. Hard to see here but the edges of the retainers where contact was made is present on most of them. She thinks the failure was her fault by taking it to 6000 RPM but it's not. A valve train that is substandard will become a secondary spring and tend to flex in unpredictable ways as RPM increases. Really bad things can happen at 6000 RPM and one must design accordingly.
After pulling the heads the news only got worse. Crack in #8 cylinder, the intake valve seat from #8 found its way in three other cylinders. A small hole in #3 piston. Initially I thought the failure was caused by the high RPM and the retainer hitting the inside of the rocker, possibly dislodging the keeper. While that is not impossible, the failure may have originated by the intake seat falling out. Anyone have any similar experience with 440 Source heads? Seats falling out that is. I have no idea what cam is in it but it has dual springs and it's a hydraulic flat tappet.
It's now my task to bring this back to life and make sure it can handle 6000 RPM under the foot of this young lady, who also has a Porsche 911S turbo. When I suggested this may have a hot cam and I can tame it down she says "oh, I don't want to loose that." Haha! OK fine with me. This thing will be Brandi proof!
