Oil pump
TECH Apprentice
Joined: Feb 2005
Posts: 384
Likes: 0
The factory 1997 pump should be a standard volume + 3/4" pickup. However, this doesn't really matter -- you can replace it with whatever you want. I would recommend that you at least replace it while you're in there -- they are relatively cheap.
I bought the Canton 15-242T pan with a 20-013 pickup for the Melling M155 pump (standard volume, 3/4" pickup).
I'd recommend the GM "white" high pressure spring, as well as the Melling oil pump driveshaft with the metal coupler. You'd have to order the spring, but the coupler can be purchased at your local auto store for around $5. (The factory coupler is nylon/plastic, which is prone to breaking.)
This was the cheapest place I found the Canton pan/pickup - pretty quick delivery: http://www.carshopinc.com
I bought the Canton 15-242T pan with a 20-013 pickup for the Melling M155 pump (standard volume, 3/4" pickup).
I'd recommend the GM "white" high pressure spring, as well as the Melling oil pump driveshaft with the metal coupler. You'd have to order the spring, but the coupler can be purchased at your local auto store for around $5. (The factory coupler is nylon/plastic, which is prone to breaking.)
This was the cheapest place I found the Canton pan/pickup - pretty quick delivery: http://www.carshopinc.com
TECH Apprentice
Joined: Feb 2005
Posts: 384
Likes: 0
I believe these Canton pickup part numbers to be accurate, but please double-check before using:
20-010 Standard Volume 5/8" pickup (M55)
20-013 Standard Volume 3/4" pickup (M155)
20-020 High Volume 5/8" pickup (M55HV)
20-023 High Volume 3/4" pickup (M155HV)
20-010 Standard Volume 5/8" pickup (M55)
20-013 Standard Volume 3/4" pickup (M155)
20-020 High Volume 5/8" pickup (M55HV)
20-023 High Volume 3/4" pickup (M155HV)
TECH Apprentice
Joined: Feb 2005
Posts: 384
Likes: 0
Nothing, as far as I know.
You see, the early LT1's (like my 1994) had a standard volume pump with a 5/8" pickup (.625") -- the equivalent of the Melling M55 pump. Somewhere within the 1995 model year, they switched to a standard volume 3/4" pickup (.750"). As such, I believe your factory pump is the equivalent to the Melling M155.
There's also the M55A, which is a standard volume 5/8" pickup with a HIGH PRESSURE release spring.
There's a lot of debate as far as the pros/cons of upgrading to a high volume pump. I couldn't personally recommend running one, but that's really up to your own discretion.
Hope I'm not confusing you.
You see, the early LT1's (like my 1994) had a standard volume pump with a 5/8" pickup (.625") -- the equivalent of the Melling M55 pump. Somewhere within the 1995 model year, they switched to a standard volume 3/4" pickup (.750"). As such, I believe your factory pump is the equivalent to the Melling M155.
There's also the M55A, which is a standard volume 5/8" pickup with a HIGH PRESSURE release spring.
There's a lot of debate as far as the pros/cons of upgrading to a high volume pump. I couldn't personally recommend running one, but that's really up to your own discretion.
Hope I'm not confusing you.
