Blade,
If you're dealing with truly "heavy oil", then you must realize that there isn't a ball on the market that will allow you to hook the ball to any great degree. When the oil is that thick, the only thing to do is get the ball rolling early and find a direct line that allows the ball to find the pocket. However, realizing that this was the limitation of original particle technology, ball companies are starting to try to make balls that will actually move in the heavy soup. From what I've seen/heard, here are some balls that might be good for you:
Lane 1 Super Carbide Bomb--Most people never see enough oil to use this monster, but it is great when the lanes are ultra-slick
Visionary Granite Gargoyle--This ball offers more backend and a greater ability to open up the lane than most particles, plus it can be shined to achieve a skid-snap reaction if you so desire. This ball is inexpensive, hits a ton and is one of the best oil balls I've ever used.
AMF Angle Evolution Tour--It's not really an "open-up-the-lane" ball, but it offers a strong arc that doesn't stop once it's started. They're discontinued and were being sold dirt-cheap on several sights. If you can find one, do yourself a favor and pick one up.
Visionary Burgandy Gryphon--Have not seen this one myself, but, from the early reviews, it sounds like a great ball for the heavy stuff. They say that it offers a solid backend move as well, unlike the early, flat roll of most particles.
Hammer Vicious Particle (Original)--This ball is an eye-sore to look at, but it offers consistency and great hitting power. It can be swung more than most high-load particles and gives a solid, arching backend move.
As you certainly know, there are tons of balls out there these days. I'm sure other posters can suggest balls that they feel would be even better for the soup. Just remember that playing in oil is about getting the ball into an early roll and finding the pocket. Don't expect to be able to stand left and chuck the ball right on the heavy stuff, you'll only be disappointed.
Gene J. Kanak
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Bowling is without a doubt the dumbest, most pointless, most idiotic excuse for a game that has ever been invented. So, what time are we bowling tomorrow?