stock oil pump for hp use

[66dartman]

Should I be concerned about using a stock melling pump with a high pressure relief spring installed in it? I have read that the drive rotor needs to be pinned to the shaft, this pump was not pinned. Just wondering if anyone has an opinion on this.

 

[ta3834bbl]

small block or big block?

 

[moper]

I havent heard of pinning a shaft..havent had trouble with rotors tho either. As long as the cleances are good, a stock pump will work fine, unless you are considering sustained 6500rpm.

 

[66dartman]

It is a small block. The rotor looks like it is just press fit to the drive shaft. I have never even given this a second look in the past, but this is the first time I have put the high pressure spring in a pump, just thinking about when the oil is cold, if the rotor might spin on the shaft. The engine will only see occasional blasts to 6500.

 

[dgc333]

If you are only going to have "occasional blasts to 6500" why bother with a high pressure spring? Just run a stock pump. The high pressure spring is only going to put addtional load on the engine and suck up power.

 

[66dartman]

My target redline is 6200 with the cam I will be using and the experience I have had with 360 engines in the past is low hot oil pressure so I am going to try the hp spring.
I would rather have good hot oil pressure.

 

[318ute]

66Dartman has asked a question here which has me wondering also!

At what point in a build should I decide to fit a hp spring into a stock oil pump? or is it better to buy a high pressure oil pump?

Is there an accepted rpm, or bearing clearances that make it necessary to build in more oil pressure?

Sorry 66Dartman I don't mean to hi-jack your thread but this has rung my bell and I need to know!

Regards,
Steve

 

[moper]

I always run the HP spring. I'd rather have the extra pressure. With good clearances, the stock pumps will go to 65psi, which is on the hairy edge of the performance envelope at 6500. If over 6K on a regular basis was in the plan, I'd run a HV pump. It's still limited by the original pickup tube demensions, (ID) but it will get more oil and therfore more pressure at those engine speeds.