In this installment we test a Scorpion exhaust system from Bavarian Autosport, which is seen here nestled inside the Khoalty carbon fiber rear diffuser.

Project M3: Part 15 – More exhaust testing and weight reduction

by Pablo Mazlumian

Today we move onto a new exhaust system we got for the car. Until now the car had been expelling exhaust fumes through a Magnaflow exhaust, which took care of sections 1 thru 3 of the exhaust system (in other words, header-back). Don’t get us wrong—for a car with factory headers and cats, this exhaust is great in both looks, sound, and a little bit of weight loss. For a car like ours, however, which runs VAC headers, it wasn’t the right combination.

The reason was more about the drone between 2200-2700 RPM. It’s a small window, but an often-visited one. Yes, we could have tried having Modified by KC weld on some dead-end, drone cancellation pipes to cancel out those frequencies, but it was going to be a trial and error labor that we couldn’t coincide the time for. We may still try something like this in the future, but for now we wanted to find something off the shelf which could work for the average Joe running a similar header set up.

So we contacted Bavarian Autosport. Until now, Bav Auto has primarily been our go-to place for factory parts—after all, they’re practically the cheapest around and been around so long they’re great to deal with. These guys do sell a lot of other performance parts, however. Two of them we’re featuring today—the Megan Racing section 1 and 2 performance mid-pipe and the Scorpion Exhaust Systems section 3 muffler. Bavarian Autosport happens to be the master importer of the latter.

Please note, as mentioned in Part 14, the car has been baseline-tested with the Megan Racing performance mid-pipe already on the car due to time constraints. In this part we will be dyno-testing the rear muffler only.

The Megan Racing sections 1 and 2 Performance mid-pipe from Bavarian Autosport features two resonators. The factory unit only has one resonator on one side. It retails $688 from Bavarian Autosport and was designed to be a direct O.E. replacement.

We’re also testing the Scorpion exhaust from Bavarian Autosport. The company happens to be the master importer of Scorpion Exhaust Systems. It retails $599. It, too, is a direct replacement to the O.E. unit.

When compared to stock, the Section 2 portions of the exhaust look similar, except for the small resonator on the factory unit and the H crossover. We’ve decided to measure and weigh everything for you.
Page 1 of 9 Next Page
Bookmark and Share
Wednesday, October 12, 2016 1:23 AM
Nice. Thanks for the weights. I imagine you could feel a reduction of 20lbs at the rear. What's funny is that the lighter your car is the more you notice weight and CoG improvements. I removed so much from my car (carbide hole saw FTW!), that my Bilsteins are now damping the car perfectly. This was unexpected to me. Not only does removing weight increase all handling metrics, it can also change the frequency of chassis vibration, which seems to give it a nice feel. Otherwise you would need to increase compression damping, which is not usually doable with most suspensions.
Wednesday, October 12, 2016 4:42 AM
There must of been some weight savings with the intake?
Wednesday, October 12, 2016 10:07 AM
Love the 8 series! I know it's big and heavy, and I can't speak to its reliability, but it has such nice lines! If it had a modern S85 or S63 powertrain, it would be a beast! If I had money to burn...
Pablo Mazlumian
Pablo Mazlumianlink
Wednesday, October 12, 2016 10:23 AM
@ginsu: yeah makes sense when you're lighter--it's a greater % drop given the same weight drop. That's interesting about the shocks. One thing I forgot to mention was that the rear muffler and battery (36 lb total weight loss between the two) are behind the rear axles, so that should help in high speed cornering, rear grip specifically.

@smoketreegarage: You know, I did think about that while writing this up, but couldn't find any numbers. I'll have to weight the intake plenum against the whole stock setup--I'm sure there was some additional loss there.

@sethulrich: Yeah it is a beauty of a car. S85 V10 would be unbelievable in that thing, or shoot you could even go on the cheap and turbocharge an S52 3.2-liter off of an E36 M3 :)
Wednesday, October 12, 2016 8:13 PM
I'm betting the urge to turbocharge your bmw will be impossible to resist. Nice ride, I love the m series, and how bmw goes full overboard with the accessories and the power to match, you know their 1000cc sport bike has cruise control!?
Pablo Mazlumian
Pablo Mazlumianlink
Thursday, October 13, 2016 10:32 AM
@theneil: the urge isn't quite there as long as I've got the Supra. I've contemplating supercharging it--again, while I've got the Supra. If I would sell the Supra then for sure this car would be seeing some boost. I don't care what car it is, I at least need one heavily boosted car, ;).
And yes that new BMW crotch rocket is unbelievable.
Sunday, November 27, 2016 1:49 AM
This exhaust lacks a true crossover, of course it's not doing a proper job scavenging. I would toss it into the trash and get something with a proper X pipe.
Pablo Mazlumian
Pablo Mazlumianlink
Monday, March 06, 2017 5:22 PM
TheAxiom, you are correct. We need some sort of cross-over. I will be putting back the stock section 2 and testing right away.
Anonymous User
Anonymous Userlink
Tuesday, March 14, 2017 3:13 AM
Post Comment Login or register to post a comment.

MotoIQ Proudly Presents Our Partners:

© 2018 MotoIQ.com