Before i start I want to apologize. This is for a circle track car this time, not the Chevelle (sorry) but i know there is lot of people who know what they are talking about on here.

I just wanted to see if anyone has used a stock volume big block oil pump in their small block. I know it can be done just looking for experience. I want a little more volume but not necessarily go all the way to a HV pump. I was thinking that the stock SBC had 1.2 gears and HV had 1.5 gears and the stock BBC i think was 1.3?. I thought this would be about right in the middle and provide increased volume without being excessive.
We turn up to 7200 regularly and have used a stock SBC with sythetic oil and had no problems but there are times i wish we had another 10psi oil pressure. At operating temp on the track we usually max out about 55-60psi. I just thought maybe a little bigger pump would help get more oil into the motor.

I always used a stock Melling pump in my circle track motors. All you need to do to get your higher oil pressure is to get the high pressure relief spring, or do like I do and drive the pin out that hold the relief spring and then shim the spring with two #8 flat washers. Reinstall the pin and you now have a high pressure relief spring. BTW the motor that I built was a 350hp NASCAR Charger motor for a 3/8 mile short track and we ran between 5600 off the coners to 7200 going into the corners.

Good Luck.

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R.J.
1972 Chevelle
TC Member #1525
RJ's website updated 12-1 (http://www.buffnet.net/~airrj/)
2003 Northern Chevelle Gathering (http://www.angelfire.com/folk/canam/page35.html)

I guess we could do that to the spring. In one motor we have a HV pump and it runs upwards of 70-75 when it is hot and the one with the std pump that hits about 60. Just thought a little more volume would be the way to go. I guess in the long run we have had no problems with the std pump the way it is so maybe we should leave well enough alone. I mean we change bearings every 25 nights so we keep clearances in check.

The way I understand this topic is that a BB oil pump is smoother operating b/c it has more and bigger teeth on the two gears. This smoothness equates to less distributor shaft movement or deflection, if you will, and this makes timing, (or sparkplug firing), smoother throughout the rpm operating range...

And a BB pump will take more power to turn over so I would think real hard about making a change to one if I'm not having any serious oilling problem's now...

Hope this helps. pdq67