Yes, this can be confusing. I spent several months just finding information to make that simple "Biggie" kit for the intercooled cars. I will cover just four different styles of filters that are used by most Buick turbo owners.
The small Buick filters for the V6 have an 18mm thread and a small diameter sealing ring gasket. All of us can use these in the normal AC sizes of PF 47 and 52.
The large Buick filters for the V8 have a 13/16" thread and a small diameter sealling ring gasket. This is the AC size PF 24 and is the size I selected for my kits with a new adapter bolt used to change the thread sizes.
The large Chevy filters have a 13/16" thread and a large diameter sealing ring gasket.
The large Ford filters have 3/4" thread and a small sealing ring gasket. They are "almost" a direct fit, but the threads are just enough different where some filters will pull right off and some will seem like they fit. Too scary for me.
So, from this you can see the only filters which are direct mount for the Carb/Turbo cars would be the small Buick filters. If you desire to run a large filter, you will need to add some type of adapter system such as the one Fred is using. They only cost about $70 from Summit or PAW. You can get filter mounting adapters for Chevy V8 or for Ford filters, single or double filters too. You can even get ones to run your own turbo feed line, if you desire.
There are several things to consider when you go about changing the filter you put on your motor. Here is just a couple.
The GM style filters we use have an anti-drainback valve to hold oil in the filter after the motor is shut off. This is important for our turbo motors and some brands have better vlaves than others. Not all Ford filters have this feature and you will need to ask. If the parts store can't tell you, get the telephone number of the company from them and call.
GM puts the filter by-pass valve in the block or in the filter adapter, as it is on our V6. Ford puts the by-pass valve in the filter itself. And these by-pass valves have different pressure ratings. The one on our motors is rated about 10PSI and you can find in the Ford filters it can be 6-8PSI. Yes, this means that by using the Ford filters you can have two ways for the oil to by-pass the filter and the one in the filter is set lower than the one you already have. Again, you will need to ask about the filter you intend to use.
The small Buick filters for the V6 have an 18mm thread and a small diameter sealing ring gasket. All of us can use these in the normal AC sizes of PF 47 and 52.
The large Buick filters for the V8 have a 13/16" thread and a small diameter sealling ring gasket. This is the AC size PF 24 and is the size I selected for my kits with a new adapter bolt used to change the thread sizes.
The large Chevy filters have a 13/16" thread and a large diameter sealing ring gasket.
The large Ford filters have 3/4" thread and a small sealing ring gasket. They are "almost" a direct fit, but the threads are just enough different where some filters will pull right off and some will seem like they fit. Too scary for me.
So, from this you can see the only filters which are direct mount for the Carb/Turbo cars would be the small Buick filters. If you desire to run a large filter, you will need to add some type of adapter system such as the one Fred is using. They only cost about $70 from Summit or PAW. You can get filter mounting adapters for Chevy V8 or for Ford filters, single or double filters too. You can even get ones to run your own turbo feed line, if you desire.
There are several things to consider when you go about changing the filter you put on your motor. Here is just a couple.
The GM style filters we use have an anti-drainback valve to hold oil in the filter after the motor is shut off. This is important for our turbo motors and some brands have better vlaves than others. Not all Ford filters have this feature and you will need to ask. If the parts store can't tell you, get the telephone number of the company from them and call.
GM puts the filter by-pass valve in the block or in the filter adapter, as it is on our V6. Ford puts the by-pass valve in the filter itself. And these by-pass valves have different pressure ratings. The one on our motors is rated about 10PSI and you can find in the Ford filters it can be 6-8PSI. Yes, this means that by using the Ford filters you can have two ways for the oil to by-pass the filter and the one in the filter is set lower than the one you already have. Again, you will need to ask about the filter you intend to use.
....oh well...
