OK guys,
so after almost one year the engine was built and dynoed today. However, we have an issue....
So as i said, i went with the 408 cleveland stroker kit and speedmaster 220cc 3v aluminum heads. All internals (valve train) that came with the heads have been replaced with quality parts.
Anyways, i bought 3v speedmaster intake as well to match the heads.
So long story short it made 422 HP at 4600 RPM and 482 lb-ft of torque at
same 4600 RPM
at 4700 RPM fall of on its face hard... It goes down to 429 lb-ft of torque and 384 HP
from then down it keeps dropping power. We never pushed it past 5000 RPM...
So builder thought it is ignition problem so we changed ignition and boom same problem at same RPM.
Changed spark plugs, wires, checked Fuel Pressure, cleaned fuel filter, changed 3 carbs ... Same problem at the same RPM
They said it should not be valve float since they checked the spring pressures and it is matching cam...
Suspected lifters issues but ruled that out later because it does not matter if its cold or warm engine pull it drops down at 4600 RPM.
You can tell that it wants to climb up higher but something is happening and it is falling on its face.
So the last thing it was suggested is to replace crappy Chinese intake.
It is the low profile speedmaster intake manifold.
Overall , i am happy with the build and 422 HP and 480 lb-ft of torques at 4600 RPM but i feel that it is much more capable than that
So i am planning to replace the manifold with again speedmaster highrise 3v manifold but i am not sure if I am going to have clearance issues with my hood.
Do you guys think that manifold could be an issue and what other intake manifold could fit these speedmaster 3v heads?
I am attaching dyno sheet.(nice Christmass tree )
Thanks
Alex