June 16 - Finishing the Bottom End

Our newly modified oil pan arrived via UPS yesterday so we now had everything we needed to complete the bottom end of the engine. We trial fit all the components to make sure everything fit together and turned the crank a couple times to make sure our clearances were good.

We had purchased an ARP oil drive shaft. Not only is this shaft extra strong, but it is thicker in the middle than on the ends so the retaining clip can't slide down when the distributor is removed. The retaining clip fits on the shaft and prevents it from coming out of the oil pump.

  
 

The oil pump went on easily but we realized after the fact that we should have bolted on the oil pickup before installing the oil pump. The lower oil pickup bolt was very hard to get to once the oil pump was installed since the main girdle extends right under the pickup tube. But I was able to get in with a small open-ended wrench once I got the bolt started.
Once we had the oil pickup bolted in place, we installed the washers and nuts on the main girdle. For all our bolts, we used blue locktite threadlocker to make sure they won't come off.

The main girdle fits on top of longer than normal main cap studs to provide extra strength to the bottom end of the engine. Since this was purchased from DSS at the time we purchased the short block, it had already been clearanced (cutouts machined out of the girdle to avoid interference with the rod bolts and crankshaft) and fit perfectly.

Once the main girdle was torqued down to spec, we installed the DSS windage tray. This is made from machined

 
  aluminum and bolted right to the main girdle. The windage tray prevents the oil in the pan from being churned up by the crank. This improves oil flow (since less air is sucked in by the oil pickup)  and provides a small increase in horsepower.

We used 3M adhesive on the oil pan gaskets and installed then installed the pan. We ran into a minor

problem with one of the bolts. Because of the clearance requirements of our beefier Sportsman block, there is not a lot of space around the bolt holes at the back of the pan. One of holes was too close to the pan to allow our ARP bolts (which have a flange around the hex head) to fit. We found a socket head cap screw that did the trick, and finished the bottom end of the engine.

In order to allow the valve covers to fit over our larger than normal rockers, we had to remove the oil baffle and cut down the baffle support posts inside the covers. To prevent oil from splashing out through the crankcase vent, we found a rubber PVC gasket with a built in oil baffle. This was installed with 3M adhesive inside the oil filler (which has the vent for the crankcase). Hopefully, this will do the trick.

The crankcase vent will be connected to an external overflow tank (to catch any oil that might leak out) which has an integral breather.