A week after picking up the Bimmerfest long term review/project 328i in New Jersey we manage to put 900 miles on the odometer while trekking back to Massachusetts. Arriving back in MA early last week just in time to head to Turner Motorsport. TMS's facility in Amesbury, MA is 35,000 square feet of BMW heaven. In one location TMS packs a championship winning race team, Dynapack dyno, thousands of OEM and aftermarket parts and 4 service bays with factory trained techs. In a place that is use to rare an unique BMWs (they have frozen gray E92 M3 sitting outside) our project 328i in Melbourne Red still turned heads. We had a busy day planned with the F30 328i and after the initial buzz of having the F30 in the house died down we got to work.
2012 F30 328 on the Dynapack Dyno
It is common knowledge amongst BMW enthusiasts that BMW under rates their motors from the factory. Knowing what a car really puts down is key for real world shopping comparison of the F30 328i and the 335i. Plus it is fun to know what the motor is really putting down to the pavement and that's where the dyno comes in.
Tuner has Dynapack dyno system, unlike a rolling road style dyno (Dynojet or Mustang) a Dynapack bolts directly to the drive hubs in lieu of the wheels and the car weight sits on the "packs" (red boxes in the pictures/video). There are pros and cons to each system, Tuner has this style to tune race car. With the dyno rated to 1000HP and accustom to torture from TMS E92 M3 race cars I don't think our F30 328i set any dyno records, but we sure did beat the BMW factory rated numbers!
BMW rates the 4 cylinder turbo N20 engine in the 328i at 240hp and 260 ft-lbs of torque for the US. The N20 is the first 4 cylinder engine available from BMW for US cars in years. BMW knows they couldn't afford to screw up the engine in the bread and butter 328i, the most purchased configuration for the 3 series. It seems the engineers understood this and gave the N20 the required power and then some. After 12 dyno runs we got a best run of 250 horsepower and 275 ft-lbs of torque, and that is at the wheels! If we could dyno the engine at the flywheel we would have about 20% more power then BMW rates the motor for. To say that BMW has underrated the 328i horsepower and torque would be an understatement. This underrated power was most likely done to ensure that on paper the 335i reigns supreme in the power department.
What what does the F30 328i weigh?
With a big smile from the dyno runs it was on to find out how much the 328i weighs. Besides raw power number the next big performance number is power to weight. You can have 500 horsepower and get beat by someone with only 250 in a lighter car.
The nice thing about hanging out at a race shop is they have all these cool toys. TMS pulled out their race scales so we could figure out what our car weighs. There was a lot of apprehension around the shop about the weight. BMW has been packing on about 200 pounds for each new generation of car. If the F30 3 series grew another 200 lbs it was going to be hard to continue calling it a sports car.
BMW lists the curb weight for the 328i with a manual transmission at 3406 pounds but curb weights and real world weights are often worlds apart. I am happy to report that with 2.1 gallons of gas in the 328i it weight in at 3367 lbs. Not the lightest feather, but not a pig either. We weighed a E90 330i sedan for reference and with three quarters of a tank of gas it was just under 3400 lbs. Had both cars had the same gas the weights would have been just about even. Not bad considering the F30 328i is almost 4 inch longer then the E90 sedan.
Wheel Fitment Testing
One of the easiest ways to change the look of any car is swapping out the wheels. Ditching conservatively styled wheels and narrow tires for some aggressive wheels and wide tires can change the entire feel of the car. It is also a good opportunity to ditch the factory run-flats.
Properly sizing wheels and tires to a new car when you're upsizing the rim diameter and width and adding bigger tires can be challenging. To started narrowing down where we needed to be for sizes and offsets we tried a few different sets of 19" TMS has around. I had high hopes for the 19" E92 M3 Challenge wheels custom painted with a red ring that almost matched the car color. The fronts fit OK but when we put the rears on and lowered it down there was no way it was going to work, unless we were going for the truck look.
We tried a few more wheels and didn't find anything that was perfect but were able to get some number that will work for a set of 19" for the F30. We will be putting aftermarket 19"s on soon, stay tuned for exact fitments.
Up on the lift - We get under the F30
The final stop on our F30 exploration mission was on the lift. Despite many new things about the F30, on paper much of the F30 suspension was carried over from the E90. The F30 has a double joint strut suspension up front, the E90 has a double joint strut suspension up front. The F30 has a 5 link rear suspension, so does the E90. The real question was what about the suspension has changed. Oddly not much (detailed review coming soon), the control arms are beefed up in a few places and have slightly different bends here and there but I would guess in a pinch you could use an E90 suspension arm as a substitute in more then a few places. The most surprising was the use of steel in many places where the E90 benefited from aluminum. With BMW making so much effort in other places on the F30 to save weight using so much steel in the suspension and sub-frame was quite surprising. Was this cost savings, crash protection or something else has yet to be determined?
Continuing to poke around the underside of the F30 a few other interesting things stood out. Gone is the vacuum actuated exhaust valve, so no more "golf T mod". In its place is an electronic version, the life span on the valve was a big question mark for the techs at TMS.
Heading up to the front of the F30 328i there are two really interesting things. The variable sport steering rack has a absolutely massive motor on it, and it hangs down really low. The motor housing looks sturdy but the placement means it is going to take hits from anything you run over. Wonder what the car will be like with no power steering after running something over at 80 mph. Someone should make a guard for it, sounds silly but I bet after replacing one you won't want to risk paying for another one.
Just behind the steering rack is the other big surprise. The oil pain on the F30 N20 328i is plastic! It is likely a composite plastic of some sort but it has some give to it. Both the steering rack and oil pan have a large under tray cover over them but the cover is similar to a stiff felt, and only 3/16" thick at best. It is not the hard plastic cover you'd expect and isn't going to do much to absorb impacts. I could easily see something bouncing off the road right into the oil pan and cracking it. Unless you catch that right away, its game over for the engine.
There are another 10 or so interesting things that the TMS engineers pointed out about the suspension. We will have a complete F30 suspension and chassis review coming soon so stay tuned.
A BIG thanks to Turner Motorsport for the hospitality and use of their facilities. TMS has a F30 335i on the way so look for an in depth review of the TMS 335i soon.
Recent BMW News
Latest Forum Discussions