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So ive tried severall options of drop base air cleaners and still no luck .My car is a 1980 olds cutlass supreme with a 455 installed with a performer intake on it.The best i can do is a modified tornado air cleaner base and a 2 inch air filter. I tried the jegs chrome cheapo and beat the heck out of it but it just wouldn't work with a 3 inch cleaner. i heard that the drop base for a 72 ls1 corvette would work so i bought one to try it out . I had to modify the throttle cable bracket and it actually came close to fitting with a 3 inch air cleaner and the top breather that summit offers. I did have the clearance but the base wouldn't fit tight to the carb as it hit the front fuel inlet . (chevy fuel inlets exit out the side ) I bet with some mods to the drops base you could get it to work but i didn't want to beat up the 100 dollar part so i opted to send it back. im not even sure how much better a 3 inch over a 2 inch would be. would love to hear if others have found a viable solution
Unfortunately i’m no help with the drop base air cleaner as my ‘80 Supreme is 350 Olds powered. I am interested in what you find out as it may find a 455 in the future.
How about some pics of your car, would like to see it. Mine is coming along slowly but looking to drive it this summer.
Keep in mind that installing a tall, higher flowing intake is kind of worthless if it forces you to run an air cleaner that becomes the flow restriction. Airflow into and out of the engine includes the ENTIRE flow pathway, from air cleaner inlet to exhaust tips. Any one of those can be the restriction.
When we built this motor and put the performer intake on it I knew it was going to be close but I took a chance on it . I really don’t know if the 2 inch air cleaner is a restricting point or not but always figured a little bigger wouldn’t hurt .
Doesn't the engine height change dependent upon which mount set-up was used when the 455 was installed?
OK, now you're just doing this to spin me up...
First, there are only ONE set of motor and frame mounts that fit the 1978-1988 A/G-body cars. Second, for the eight millionth time, if motor and frame mounts are used as a matched set, the crank centerline is in exactly the same place. The A-body mounts are shown below.
When I bought this car it had a 307 olds motor in it . I pulled that out ordered a set of motor mounts for a 307 olds and bolted them to the 455.
Every single 307 came from the factory with the 2328 so-called "big block" motor mounts. The frame pads for the 78-88 intermediates (and the 77-90 full size) are not the same as on the earlier cars. From 1973-on, every single V8 that Olds made used the 2328 mounts.
my frame pads . I’m pretty sure the motor is sitting where it needs to . Just a matter of minimal clearance with the performer intake . Question , is there a test I can do to figure out if my air cleaner is restricting flow ?
First, there are only ONE set of motor and frame mounts that fit the 1978-1988 A/G-body cars. Second, for the eight millionth time, if motor and frame mounts are used as a matched set, the crank centerline is in exactly the same place. The A-body mounts are shown below.
Nope, I wasn't trying to "spin you up" and had no intentions to rattle your cage, just politely asking whether or not the wrong motor mounts could have contributed to part or perhaps all of the OP's problem. Anyway, I hope your day gets better.
I just sold one at the Portland Swap Meet but see if a buddy has a covette LT1 base. They have a deep drop. Problem is they don't fit carter/edelbrock carbs without mods. Fits Holley double pumpers just fine.
Inlet air testing I saw somewhere showed that those top entry filter lids don't work well even when there is free air above them to flow straight in through the top. When the hood is closed tight to the top of those filter lids, they are worse still as the thickness with those pleats on top costs you about an inch of clearance that you could have used on a taller open element filter, which is a much better way of getting air in there. You will want to find the flatest top lid you can, the deepest drop base you can make fit, and the tallest open element filter that will fit and still allow the hood to close.
It will take some time and money to make that Corvette repop deep drop base bottom plate work but I managed to make one fit atop an Olds Qjet in a 1967 Vista Cruiser with a 455 and a taller-than-stock intake. I massaged it a bit with a ball pein hammer to get clearance where needed in a few areas. There was also a vent pipe in the drop base for the PCV system I had to relocate. The big interference was with the olds Qjet front inlet fuel fitting as you noted. You couldn't cut or hammer to make it fit as that inlet fitting wanted to go right through where the bottom of the filter element would be. Only way I could work around that was to remove the straight 2" cylinder housing the fuel filter and replace it with this fitting #2215 from quadrajetparts.com. You will need to bend up a new fuel tube or do some alternative hose material (AN for example) with a conversion fitting as needed at the ends. Lots of fitting work but it can be done and you will then be able to jam a reasonable sized filter element. I was able to get a 3" tall element in there, but you have a different vintage Olds so not sure what you will get.
Quantity
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Price for each
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$19.96
Your savings
-
20%
Inlet ‘Banjo’ Fitting for 1"-20 threaded castings. Converts inlet position from front to side or side to front. 5/8-18 thread is used on 3/8" diameter fuel lines. Allows easy positioning of fuel line.
No machine work required, banjo conversion kit contains everything you need including gaskets. Banjo fitting design allows use of most OEM short- style fuel filters. (Note: Mercury marine filter #2254A is longer than our other short filters and is not recommended for use with this banjo fitting. Use #2254 screen filter instead as it is a shorter fiter.)
Quantity: 1
Replacement gaskets available:
#2232 (white/clear gasket, need 1)
#2233 (Red/fibre gasket, need 2)
1" inlet fittings are found on all 1972 and later automobile and truck Quadrajet carburetors.
1" diameter inlet carburetors can be identified by the location of the inlet gasket, it will be located at the very forward edge of the inlet fitting. After installation of the 1" inlet fitting on the carburetor, the inlet gasket is not visible.
Inlet air testing I saw somewhere showed that those top entry filter lids don't work well even when there is free air above them to flow straight in through the top. When the hood is closed tight to the top of those filter lids, they are worse still as the thickness with those pleats on top costs you about an inch of clearance that you could have used on a taller open element filter, which is a much better way of getting air in there. You will want to find the flatest top lid you can, the deepest drop base you can make fit, and the tallest open element filter that will fit and still allow the hood to close.
It will take some time and money to make that Corvette repop deep drop base bottom plate work but I managed to make one fit atop an Olds Qjet in a 1967 Vista Cruiser with a 455 and a taller-than-stock intake. I massaged it a bit with a ball pein hammer to get clearance where needed in a few areas. There was also a vent pipe in the drop base for the PCV system I had to relocate. The big interference was with the olds Qjet front inlet fuel fitting as you noted. You couldn't cut or hammer to make it fit as that inlet fitting wanted to go right through where the bottom of the filter element would be. Only way I could work around that was to remove the straight 2" cylinder housing the fuel filter and replace it with this fitting #2215 from quadrajetparts.com. You will need to bend up a new fuel tube or do some alternative hose material (AN for example) with a conversion fitting as needed at the ends. Lots of fitting work but it can be done and you will then be able to jam a reasonable sized filter element. I was able to get a 3" tall element in there, but you have a different vintage Olds so not sure what you will get.
Quantity
1+
10+
Price for each
$24.95
$19.96
Your savings
-
20%
Inlet ‘Banjo’ Fitting for 1"-20 threaded castings. Converts inlet position from front to side or side to front. 5/8-18 thread is used on 3/8" diameter fuel lines. Allows easy positioning of fuel line.
No machine work required, banjo conversion kit contains everything you need including gaskets. Banjo fitting design allows use of most OEM short- style fuel filters. (Note: Mercury marine filter #2254A is longer than our other short filters and is not recommended for use with this banjo fitting. Use #2254 screen filter instead as it is a shorter fiter.)
Quantity: 1
Replacement gaskets available:
#2232 (white/clear gasket, need 1)
#2233 (Red/fibre gasket, need 2)
1" inlet fittings are found on all 1972 and later automobile and truck Quadrajet carburetors.
1" diameter inlet carburetors can be identified by the location of the inlet gasket, it will be located at the very forward edge of the inlet fitting. After installation of the 1" inlet fitting on the carburetor, the inlet gasket is not visible.
Good info i wish i wasn't so quick in sending back the lt1 drop base . I may get this fitting and rework the fuel lines then keep an eye out for another drop base. if it all comes together i will revisit this thread with the results Thank you
April 20th, 2024, 12:06 PM
Inlet ‘Banjo’ Fitting for 1"-20 threaded castings. Converts inlet position from front to side or side to front. 5/8-18 thread is used on 3/8" diameter fuel lines. Allows easy positioning of fuel line.
