Afr heads with PAC 8002 spring upgrade.
#191
Registered
MT 100 % correct but you'd think most going to different ratio would consider such such. If they don't urn they don't belong changing ratio. Although I have to be honest on lower hp builds 550 and less ive done it with no changes. But that's pure luck perhaps or just the way alignment worked out and nothing changed on valve tip. But I will say lobe profiles etc have changed much since then but regardless anybody who doesn't check pushrods length even on stock rebuild is asking for trouble.
#193
Registered
Duration itself, is in a way a mathmatical result of what a particular engine may need, to operate at a given RPM.
Just fooling around, but for example, plugging in a 4.25 bore, x 4.60 engine, (565ci),
a 236* intake lobe, would max out at 5952 RPM. Adding 3* at .050, would make it a 239*, and now, that is good until 6067 RPM. So, RPM capability went up 100rpm, just from the rocker change.
For that engine to achieve 107% VE, you will need a cylinder head that can flow 345CFM, at peak piston demand or 74* crank angle.
Just fooling around, but for example, plugging in a 4.25 bore, x 4.60 engine, (565ci),
a 236* intake lobe, would max out at 5952 RPM. Adding 3* at .050, would make it a 239*, and now, that is good until 6067 RPM. So, RPM capability went up 100rpm, just from the rocker change.
For that engine to achieve 107% VE, you will need a cylinder head that can flow 345CFM, at peak piston demand or 74* crank angle.
I thought you ran FullForce's 540 motor on the sim and came out with around 250 at .050" ?
#194
Registered
#195
Registered
http://www.offshoreonly.com/forums/g...9-years-2.html
#196
Geronimo36
Gold Member