Installation Time: Afternoon
November 04, 2019
A for AM but a C- for GMS
I initially ordered a GT350 TB for my 2017 GT. But I found out after the install that you NEED a tune if you want the GT350 TB To work at all. Even after the tune and extensive talks with BAMA, there was still surging.
So I decided to try this GMS TB next. It’s been a fairly disappointing experience. The first thing I noticed is that it doesn’t come with any instructions, which probably wouldn’t be a big deal because the TB swap is pretty straight forward. But the instructions would have been great in my case because I found out that it was also supposed to ship with an adapter cable because the plug on the TB doesn’t match the OEM plug (I’m still not sure why they chose to do that). GMS wouldn’t overnight the cable to me so I needed to uninstall it and go back to the OEM setup, tune and all. The adapter finally arrived And is installed so I’ll post an update soon. To his mod should’ve only taken 30 minutes at the most. But it took me several hours due to playing musical TB’s and changing the tune each time.
Aside from the adapter issue, the fit and finish of the GMS TB is nice. This is machined rather than cast, and it has a nice black anodized finish. It’s obvious that there were some opportunities to reduce the weight of it if they had done more machining, but I doubt the added weight will be noticeable. Just another example of where they chose a cost cutting measure.
There weren’t any other issues with the install. But I would DEFINITELY recommend a tune, regardless of what anyone else says. And I would recommend a CAI with it. If you’re going to remove one restriction, you might as well remove all the other bottlenecks for the intake.
If performance is on par with other TB upgrades I’ve seen, then this should improve the responsiveness of the engine nicely, and it’ll certainly make a difference that you can feel with the butt dyno.
But for the retail price, I can’t recommend this over the BBK. GMS has some work to do before they’re in the same league. If you can snag it on sale, then it may be a good option to try, but make sure you’ve got everything you need before you start the mod.