Ok i came up with this project after seeing the pricing for the oil cooler kits that are out on the market for our cars , and unlike some people i just did not want to put 900-1k into a oil cooler because i knew it could be done for less. This will not be a mile long , short and to the point !!! So on to the good stuff ,
Step 1: purchase the parts depending on where and how you want to mount it will determine the fittings ie: straight 90 degree , 45 degree and so on , and obviously the length of your lines. You can use steel braided or the ultra light black or plain rubber , it is your choice it will be close to $10 a foot. The size core you choose will also be your choice i used a 11 by 4 1/2 Earls super cool core. If you have a 335i you will have to make custom adapter fittings to tap into the oem housing purchase the oem plugs and 2 STAINLESS steel 90 degree -8 and cut the pipe end threads off , drill the oem plugs out to 3/8 inch and tig weld the fittings together all fittings and lines used are -8. Note
if this is a 335 application and not a 135 the custom fittings need to be clocked so that they are facing the drivers side of the car for clearance for the hood
Step 2: remove the cowl and the engine cover , next you will have to remove the oil thermostat remove the top t-stat housing bolt so the cover can be removed pull the t-stat and spring out and reinstall the t-stat cover and the housing bolt. once that is done the engine cover and cowl can also be reinstalled . next mount your cooler again location is your preference , obviously somewhere there is air flow !! run your lines and fittings! and make sure they are tight you do not want a leak
Below are a few photos of the install the one with my finger in it is the T-stat housing cover that need to be removed in the last photo you can see the t-stat and the spring . If there are any questions regarding this PM me and ill get back to you , like i said it is not super in depth ! Have fun .