Oil Pumps High Volume vs Stock

Well before I take my Fiero on its 5000km run to Las Vegas and back I wanted a little bit of insurance that the heat would not cook a bearing. I have always installed high volume pumps in any 2.8 I ever rebuilt, but I never took pics of the pumps to show the comparison. So today when I took the pan off of my 88GT I decided to take some pics and post a quick right up. I put both pumps completely submerged in oil in a bucket and drove them with my drill. The stock pump produced a spout about the size of a dime coming 2-3 inches above the oil level. The High Volume pump produced a spout about the size of a quarter coming about 3-4 inches above the oil level in the bucket.

So here are the pics.

Note the much larger body of the high volume pump, this is to accommodate the larger pump gears.



Note the larger oil pump exit hole. These pumps don't supply any more pressure than a stock pump would put out, what they do is simply pump more oil so even when your engine is hot and the oil starts to thin or a bearing starts to wear, the extra volume of oil keeps your pressure up. I believe the max either pump will produce is 100psi before the pressure relief spring opens up. You can change to a higher spring however there really is no point in running a motor at over 100psi.



Next note the extra arm that is tack welded to the pick up tube. If you have ever had a pick up tube come off and had to drop the pan just to put that damn tube back in, this pump is worth it just for that simple fact. It is bolted in rather than simply pressed in. (you do have to press it in, but the bolt holds it from ever coming out)



One other thing, is that with a high volume pump, you can safely run 5w30 full synthetic even on an older engine that has oil pressure problems when running on the high side of your operating temp.

Running with this pump on 5w30 Mobil One, even on the hottest day and the car at over 105c (220F) I have never seen the pressure drop below 40psi even when I did manage to kill a main bearing due to excessive nitrous use and over revving.

This pump was purchased from a local parts store, it is a Federal Mogul High Volume Pump for the 2.8 Chevy V6. I will see if I can look up the part number for it. I don't have my receipt for it as I purchased it a long time ago and it has been sitting on my shelf waiting to go into a motor.