Welcome to the final installment of this three-part series. In this post I will be wrapping up the series in which I have documented the installation and reasoning behind why I chose to do these specific upgrades. If you are new to the blog, or you haven’t yet read the first two parts… Please, click the links below to part 1, part 2 and get yourself all caught up.
In Part 1, installed a Unit 2 fab baffled oil pan and Spoon Sports rigid collars. (click link below to read)
In part 2, I installed Giro Disc front rotors, TI shims, and Carbotech xp12’s. (click link below to read)
And in this post (Part 3) I will be installing A 27WON Rear motor mount, 27WON “boost tubes”, and changing the transmission fluid from GM synchromesh to Motul gear 300.
Even though this series is three parts long and took nearly 6 weeks to fully get released, I did all these modifications/upgrades in just two days. In an attempt to not bore you by writing a 10k word essay about everything at once, I decided it was best to break it up into three parts. Also, to keep things interesting on the blog I sprinkled in some other content every other week (which is why it took 6 weeks to finally get to part three).
Here we go! On to Part Three.
Jumping right in, you’ll see below the 27WON RMM with the 90a durometer bushing and the Boost Tubes.
You may remember that when I first got the FK8, I immediately upgraded to the Hasport 62a rear motor mount but was underwhelmed. IMO the Hasport 62a rear motor mount wasn’t noticeable and I had even mentioned in my blog post: That I felt like the Hasport RMM’s that we had installed in Angie’s FIT and my 8th gen had a more noticeable increase in performance. Upon installing the Hasport 62a RMM in the FK8, I hardly noticed any added NVH. For some, this is a good thing and quite honestly, if you only daily drive your car and are looking for something to help reduce (not eliminate) wheel hop… The Hasport 62a is the way to go. However, if you are really beating on your car and are looking to completely eliminate wheel hop you will need to get a much higher durometer urethane bushing in your RMM.
Below you can see the 27WON Boost Tubes. I wanted to upgrade the intercooler piping for a few reasons:
- OEM rubber tubes are known to be a weak link and can actually rupture or tear under extreme conditions.
- Silicone (any brand) will not heat soak like the OEM rubber tubes and can help lower IAT’s.
- Silicone, especially the 27WON tubes (since they have wire wrapped in them) don’t expand as much and can increase spool time.
Of course, most of that is in negligible amounts and might not even be noticeable to some. But for me, because I was trying to only further postpone the inevitable overheating that so commonly plagues our cars, I was grasping at every straw possible.
Below you can see some comparisons between the 27WON and Hasport mounts. Right away you can see the Hasport mount has rubber at both ends and the 27WON only has it on one end.
There is no hiding the fact that the 27WON RMM is going to increase your NVH… But it will also greatly increase your performance as well.
You may have noticed that some of the pictures are shot with my phone. This is because while editing the pictures I took of the install process, I somehow managed to accidently delete them. SO, to get the pictures I have below, I had to jack the car back up, and remove all the metal/plastic under tray of the car just to get some pictures of the Boost tubes and RMM installed.
I apologize for not having detailed step by step pictures… BUT, 27WON offers very thorough instructions that are easy to follow.
This RMM is extremely aggressive! If you have any reservations about there being too much NVH… This motor mount is NOT for you. I will be the first to admit, when I first went to start the car after installation, I instantly regretted installing this mount.
Since then, however, I have learned to live with it. It is also true… after a few hundred miles the mount does “break in a little.” But boy oh boy, for the first hundred miles I seriously contemplated reinstalling the Hasport 62a mount that I had just removed.
The one thing that stopped me from reverting back to the Hasport RMM was how much better the car performed with the 27WON 90a RMM.
- Absolutely no more wheel hop.
- Braking was notably better.
- Car felt “tighter”.
- Throttle response was improved.
The biggest downside to this mount is the amount of noise/resonance/drone of the engine that will aggressively travel through the car above 4000 RPM’s. Below 4000 RPM’s the drone is there but not overbearing, and you can still have quite conversations in the cabin of the car.
I am also not a huge fan of the fact that it says “TOO SOON JUNIOR…” on it. I think it is a little corny, thankfully though you will never see it once installed.
Since installing the mount I have put about 1500 miles on the car. That also includes one track day where I was able to finally Sub2 are Buttonwillow. I still feel like the NVH is a bit much and there are things that have started to rattle more in the cabin. I did want to avoid this for a long as possible since the car is brand new and is exactly why I decided to get the Haport 62a RMM first.
Because of the crazy amount of NVH this mount produces, I have considered going to Hasport 62a mounts at all three motor mount locations. Hasport does make a full motor mount kit for this car, and I feel like I could benefit more from replacing all three mounts with 62a vs only replacing one mount with a 90a urethane.
As of now though, I have learned to live with it and like I stated above… The performance increase is worth the NVH byproduct.
Inconclusion, I am extremely satisfied with the improvements made to the car after installing the 27WON 90a billet RMM. It not only improves everything I listed above, but it makes the whole driving experience much more fun because you feel like you are driving more of a race car rather a daily driver. The mount gives the car character and although it may not be for everyone… It is great for me.
The RMM is so easy to install and is also relatively cheap that it wouldn’t even be that big of a “risk” for you to try it out. Plus, if you don’t like it, you can always resell it.
Now let’s jump into the 27WON Boost Tubes. As I mentioned above, I lost the pictures of my install process for not only the RMM, but the boost tubes too. Again, 27WON does provide unbelievably detailed step by step instructions to install all their products.
I bought the boost tubes as an attempt to combat overheating. You could say I was so desperate that I had drank the Kool Aid. I had really believed that the silicone tubes would help decrease the IAT’s thus allowing me to run hard for a few more laps. But, and I’ll admit I’m doing a little foreshadowing here… There were much more drastic measures that needed to be taken.
It is somewhat of a pain to install the boost tubes, and this is because you will need to remove your battery and battery tray. It is necessary to remove the battery and tray so you can access the small silicone coupler that joins the aluminum intercooler pipe to the throttle body. This small rubber tube is the main one that ruptures and creates boost leak problems. Because of this I highly suggest NOT skipping that part.
Below you can see I have removed the battery, battery tray, and airbox. You will need to also unbolt and remove the aluminum intercooler pipe that runs to the throttle body. Removing it will allow you to easily access and remove the throttle body coupler.
Below you can see the small coupler attached to the throttle body. It is in a difficult spot to access, but it NEEDS to be done. The 27WON instructions go over the extremely specific orientation of the T bolt clamps for this area. They must go a certain way otherwise you’ll risk them rubbing on the water lines nearby.
Below you can see what the cold side tube looks like installed.
Below is what the hot side looks like installed. Because the 27WON tube is slightly larger than the OEM rubber one and I am running a KOYO radiator. I did have to trim/shave some of the plastic fan shroud to prevent any sort of rubbing that could have potentially caused a failure in the boost tube later down the road.
You can see below where I removed some plastic and rounded off the metal tab. Remember that the engine will move back and forth no matter how stiff the engine mounts you have. That movement would cause the boost tube to chafe against the fan shroud and metal tab, eventually creating a hole in the boost tube.
Below you can see more up close what I had to shave away. This is in no way the fault of 27WON! They have designed their product to fit a stock car. I happen to have a KOYORAD which is much thicker and therefore causes fitment issues for certain aftermarket parts. Hell, even the Acuity radiator hoses had to be trimmed to fit when I installed the KOYORAD. I am also not the only one to experience fitment issues after installing a KOYORAD. Nothing against KOYO either, there is just only so much space in our engine bays.
It is just the nature of the beast. The FK8 has so much packed into the engine bay that there just isn’t much “extra” space to work with.
Again, below you can see where I had to round off the metal tab sticking off the radiator to ensure there be no rubbing issues as the motor moved under accel and decel.
Overall, the Boost Tubes are a great install for anyone looking to take away the risk of OEM tube failure. They do also make the car spool a bit quicker due to the lack of flex/expansion of them. However, if you’re planning to get them to help aid in cooling… (again I’m foreshadowing) Get the intercooler too.
I did have these boost tubes installed during my last track day at buttonwillow. As the temperatures got into the mid 70’s there was just too much heat soak going on after a few laps. This was causing the car to experience IAT’s (intake air temperatures) in the 140 range, and that was at WOT (wide open throttle) in fourth gear too. 140 degrees wouldn’t be abnormal if you were sitting in traffic, but the fact that they were this hot while WOT is not a good thing for the engine. Higher IAT’s will lower timing tables which will directly affect power output. Clearly, the OEM intercooler is just too heat soaked (foreshadowing again) and can’t quickly shed away the heat.
Last thing I did was change my trans fluid. Previously I had gone AC Delco synchromesh, but after seeing how hot the transmission gets on track days, I opted to try something that was more aimed at “racing” rather than just an OEM GM trans fluid. The Motul gear 300 is substantially thicker and in my head because it is more of a motorsports-focused oil brand this means they engineered it to withstand the toll that motorsports put on cars. I have no actual data to prove anything or back this up. But in my mind, it makes me feel better, hopefully I’m not way wrong.
Changing the transmission fluid is simple on this car. It does however require you to remove the air box (which can be cumbersome). You will also need to remove the under tray of the car as well. For some reason I haven’t done a DIY for how to do this, but if you just Google “how to change trans fluid in fk8” you will get some reliable results.
I have done one track day so far with the Motul gear 300 and I didn’t have any issues. That being said, I never had issues with the AC Delco Synchromesh either. I only changed because I felt that Motul would be better in the long run for my transmission. Let’s not get into an argument about it, there are WAYYY too many variables when it comes to transmission longevity. Plus…. I’m sure you probably know someone that uses water in their transmission, and they never have issues (I’m only joking, please don’t try that)
Please do not reach out to me asking me a million questions about the NVH of the 27WON 90a RMM. If you must ask, then it is too aggressive for you. It’s brutal, it drones, it vibrates the car, and amplifies the engine noise drastically. If you aren’t about that life, then this mount isn’t for you and there is nothing wrong that. It’s ok that you don’t want your brand-new car to rattle around like some clapped out civic with a motor swap, I’m not even mad at you for it. But if you are truly trying to increase the performance of the car then this is the cheapest easiest thing you can do to enhance the car.
Final thought on the boost tubes… Don’t only get them. They are neat, but really don’t yield much gain when used alone. This can be said for really any intercooler tubing kit on the market. The intercooler is where you are going to see the substantial gains in air charge cooling efficiency and decreased IAT’s.
Coming up in a few weeks I’ve got some BIG cooling mods coming your way. I have already installed them and will be assessing them on Saturday April 16th at the speed ventures event at LVMS outside road course. If you are local to Las Vegas, come out and say hi! And you will also be able to see the BIG cooling mods I just installed before they go live on the blog.
Thank you as always for keeping up on the blog and taking time out of your day to read my subjective opinions, and valiant attempts to type out professional blog caliber posts. If you have any questions, concerns, or just want to say hi. Please don’t hesitate to reach out. Email: Billy@Functiontheory.com, Instagram: @Functiontheory, or just simply comment on this post and I will respond. I would love to hear what you have to say, it helps keep me motivated to keep documenting and posting.