For the 850 Turbo and 850R, one of the many common, cheap mods that enthusiasts will do is redistricting the airflow to the engine. The modification is a 2 part process of using the intake manifold from a naturally aspirated Volvo 850, and the throttle body from a Volvo 960. For this, you need an assortment of parts, most of which can be found at any local pick-n-pull, for ours we sourced all of the parts from LKQ Greensboro. The first step in modifiying the 850s throttle body with parts from the 960 throttle body.
Dirty, but cheap!
So crusty!
As you can see in the images above of the stock 850 throttle body, the plate in the center has a wedge attached. At wide-open-throttle this plate restricts the amount of air entering the engine. The 960 throttle body is the same size as the 850, but does not have these restriction plates installed!
To do this you will probably need a small assortment of torx / hex bits, a screwdriver, and some small wrenches (probably only a 7mm, I used a small set of pliers). I started by removing the sensor on the side of the throttle body on both the 850 and 960, just make sure to keep them separate! The bolts on the 960 sensor were much nicer than the crusty ones from the 850, and these also featured a torx head instead of a 7mm head.
The gross crusty bolts used to hold on the positioning sensor.
There was grime everywhere, but that's junkyard cars for you.
Removing the plates from the center was very easy, I found it works best to unscrew the bolts while the plate is being held at WOT. Once the 2 screws are removed from the center the plate will slide right out. Again the 850 had very cheap screws that bent and warped easily, so I used the screws that held in the 960s plate which were much higher quality.
The 960 throttle body plate un-installed from its housing
Installation is just as simple, just hold the throttle body open and slide the new plate in. Mine required a bit on brake cleaner and steel wool to remove the excess grime from the plate and bars inside the body. Once the plate is in I could re-attach the sensor to the side.
Total time for this project was only around 45 and the process was very simple, I would definitely recommend it to anyone looking to gain a small amount of performance for cheap. In part 2 we will be installing the intake manifold from the naturally aspirated 850 into the 850R.