On oil
pressure, experts recommend 7 to 10 psi of oil pressure for every 1000
rpm of engine usage.
7 psi
+ 6000 rpm = 42 psi
10 psi
+ 6000 rpm = 60 psi
Do NOT use the Mopar Performance oil pumps! They use 21 hp! That's SEVEN more hp
then the stock pump uses! The stock pump has more then enough
pressure/volume for any hi-po application.
The stock oil pump for your car is fine, and so is the pick-up after the above modification is performed (for better oiling over 3000 rpm and 3 hp). Mopar had a few different pump/pickup/pan combos over the years and its easy to screw things up in a hurry. Just order a replacement pump for your year/engine and you will do fine.
Make sure you're using Mobil One oil- a synthetic motor oil will make more hp than a regular oil (frictional gains). Also, synthetics don't break down from heat.
I used to drag race motorcycles. Ran a 73 Z-1 900 with velocity stacks, open header, extra weight removed, rejetted carbs, sprocket change, and race fuel. My average e.t. for the quarter was 10.8 with Castrol 10w30. If I used Mobil 1 10w30, I consistently averaged about 10.65. This stuff is slick.
Robert Meier
Oil Pans & windage trays
Speaking of oil, a good baffled oil pan can help keep the oil in the pan where it belongs. Without one, the crank whips the oil up and costs hp. On a 440 Mopar V8 this is good for 15hp at 6000 rpm! Costs range from $160 to $400 for a good oil pan. The pan pictured above is from Mopar Performance (P4349146), it can only be used on 82-88 2.2 engines (and you must use the 82-86 pickup and oil pump) and will no longer be sold soon. You can always do what I did and make your own!
What your looking at is a factory 2.5 oil pan with a Moroso windage screen welded into it. It's a pain to install the pan when the motor is in the car but hey every bit counts. (pn 22912)
Got tired of killing myself trying to get oil pan off and decided to try something different, this is what's on the K-car now.
Dave St. Louis has a
pretty trick pan he built for his 16V Shadow.
2.5 SOHC and 2.2 16V owners can remove the balance shafts in the oil pan and pickup 10-14 hp for free- they are for secondary order vibrations and are not needed for normal operation. I have done several turbo and non-turbo cars with no ill effects. Some people have voiced concerns over this mod saying the shafts are need to control vibration, to which I respond that's nonsense! Did you know 88-95 2.5 Dakotas don't come with them? There is no room for them in the truck oil pan!
Just drop the oil pan, remove the 6 bolts holding the balance shafts in, cut the chain attached to the front of the crankshaft and remove it. Plug the oil feed hole, which is located next to the number 1 main cap, with a pipe plug (you will have to tap out the hole), reinstall the oil pan and your done.
Another bonus is less engine noise and a pan that holds another quart of oil.
WARNING!!!!
YOU
MUST PLUG OFF THE OIL FEED HOLE TO THE BALANCE SHAFTS
OR LOSS
OF OIL PRESSURE AND ENGINE DAMAGE WILL OCCUR!!!!
True story about balance shafts! Just learned this one from a retired Chrysler engineer- Seems the only reason the 1990-1993 2.2 Turbo III & VNT motors had balance shafts was that the guys on the assembly lines were forgetting to install balance shafts on the 1989 2.5 motors after a holiday!! It's true! The block would come down the line after a holiday or weekend and the assembly line guys would forget to install the shafts in the first couple of engines causing massive oil pressure loss.
The fix?
Install balance shafts in ALL the TURBO ENGINES as of the 1990 model year.
Oil pump passage massaging-
...note that the oil pump hole is oval while the one at the surface of the block that it mates to is round... ..take a die grinder and make the one on the block match the one on the pump... ...Ed Peters swears there is a 5-6 hp gain since pump does not sap as much power due to better oil flow.....I tried it on my carb Horizon and MAYBE picked up .10...
Angelo Taylor
