Going back to a OE style standard volume oil pump and pick up. Which one of these 2 oil pump is a OE factory replacement for my 94 Z? Im going to pick one up from AutoZone. Its a Melling unit, but I didnt know which one of these 2 pumps was the one I needed.

m - 155 - 3/4 screen inlet

m -55 - 5/8 screen inlet

 

They changed from 5/8" to 3/4" during the 94 year. I'd just go with the 3/4". But...I would get a Melling Select 10554 instead. It is a better/stronger casting than the M series and it comes with a steel collared drive shaft and 70# spring you can install.

 

3/4 inlet? Is that the same size inlet that a HV pump would have. I have the oil pickup from the HV pump. Wonder if it will size up?

I noticed there is an high pressure spring option. Good idea? Any draw backs?

 

There might be 5/8 HV pumps but that does not matter. I always use a new pickup. Use the high pressure spring. No drawbacks.

 

does the melling performance oi pump come with that 70lb spring or is it purchased seperately?

 

I think I already answered that. It comes with a standard and 70# spring.

 

Just FYI, Melling has gone back to the older heavy duty casting on their oil pumps, for the last 8 months or so all the M-55A pumps which we use on most builds have been the HD casting. The steel collared pump drive part on it's own is a part # IS-55E