Depends on the motor and the filter. If you have a real 57 235 block, then that motor uses a bypass filter. Notice the id of the oil feed lines, small. So what happens is that the bypass style filter bleeds a little oil from the mains, filters it, and then dumps it back into the pan where it is immediately diluted by dirty oil. Now, using the bypass filter will not bleed enough pressure to lower the over all pressure to the motor in any noticeable amount.
Now, install a remote spin on filter and use the largest id lines you can find. Now you are bleeding way to much oil pressure from the mains and you will lower the oil pressure in a noticeable amount.
Stock bypass filter, use the correct size lines, you are all set. Aftermarket spin on filter, yes you can use it, just make sure there is restriction the size of the id of the stock lines somewhere in the return, either by using a small id line, or some have used soldered and drilled fittings, and you are all set.
That being said, if you have a later model 261 motor that is set up for full flow oil filtration, then you can use the after market spin on with the appropriate full flow hoses.
Last edited by Dragsix; 07/16/2019 7:23 PM.
