[NB] Review: Track Dog Racing Rotrex Supercharger Kit (2024)

NB2PNW

Join Date: Aug 2020

Location: Seattle, WA, USA

Posts: 29

I've seen a few excellent reviews of the Track Dog kit in this forum - but also many more replies requesting a few more. So here goes:

I installed the TDR Rotrex complete kit (purchased new) in late 2021. My options included the Rotrex C30-84 model with an 85mm pulley. Kit included the blower, blower bracket, pulleys (tensioner and idler), TDR intercooler and piping (combo of stainless + silicone joiners), SC oil cooler and plumbing/mounts, catch can and plumbing/mounts, K&N filter + silicone intake pipe, plus a bunch of impact-plastic ducting for radiator and IC airflow (and probably a couple of odds/ends I'm forgetting). I also got the MS3Pro PnP ECU, through TDR but drop-shipped from Megasquirt.

I also got some DW 1000cc injectors and a DW200 fuel pump - but that changed later on (more to come).

INSTALL:

Overall, I'd rate the install at a 6/10 for an experienced garage mechanic - involved and time-consuming, but the bible of directions that TDR sends is extremely clear and thorough. I only had a few "monkey-from-2001-space-odyssey" moments, usually resolved by re-reading the directions. Took me about a week of evenings, plus one solid thrash on a saturday, to get it mechanically finished. Some notable moments:

• As has been mentioned elsewhere, the intercooler is a VERY tight fit with both a rad (especially an upgraded one) and an AC condenser. In theory it all works, but after reading through the directions twice I made the command decision to delete my AC (also deleted my PS on this journey - more on that later). My life immediately got 1400% better.
• Similarly, TDR recommends install locations for both catch can and SC oil reservoir in close proximity to the cruise control can. I deleted that as well because... cruise control? In a Miata? Also I'm impatient (you probably gathered that).
• this kit is really well-engineered and put together overall. But there are a few little things that you'll find are just that bit less plug and play than a power-adder kit from a more established vendor from oh, I don't know, Colorado. This is a really nit-picky example, but the silicone intake tube for the air filter sat directly on top of the front stud for the driver's side coil over, thus creating a nice little vibration-driven drill that eventually opened my SC to unfiltered air. A replacement tube and a vacuum cap over the stud took care of it, but that shouldn't have been a thing.
• the guys at TDR were incredibly patient and helpful with my stupid questions (my mechanical ability at the time was maintenance, brakes and coil-overs). Seriously can't say enough good about the customer service from Gary and the team.

I'm glossing over a lot, of course - please feel free to ask questions below about the install itself.

TWEAKS:

Other than deleting, well, everything that makes the car comfortable and convenient, I made a few other changes. Most important was injectors. The DW1000s were (according to my tuner, who I'd trust with my kids and, more importantly, with my rotating assembly), said they were very difficult to tune for idle and cruise. I thought at first they were just too much flow for my application - but turned out the FIC injectors (also 1000cc) they recommended did in fact work better for the base tune.

In general, I'd say getting the supercharged motor to run right on the MS3 was a much bigger challenge than I anticipated. I had to change tuners after the first one just couldn't get the idle to stay put once the car warmed up. It would stall out constantly at stoplights. I can't say how much of this experience is the kit vs. the Megasquirt (vs. my weirdo car, who knows?) but I do know that my prior Miata - a 99 with a totally vanilla FM Voodoo kit on it, ran like factory with zero exceptions.

The only other tweaks to the kit itself were a replaced DW fuel pump (failed on me during a Miata club drive about 90m from home - yay) and an absolutely gorgeous custom airbox made by Rob at Flipside Customs in Renton WA. the guy is an artist with a TIG. Seriously. Oh, and I'm down to an 80mm pulley. Track Dog estimates about 1psi more boost per 5mm drop, which proved accurate for me. The smallest pulley they recommend for the -84 is a 72mm. So yeah I got one of those two, waiting for the next dyno session. After that, for more HP you'd need to go to a C30-94, which flows about 25% more air - but piles the power even higher in the rev range, so it's more for racing. So of course I'll probably be ordering one for my 90% road car very soon. Sigh.

SUPPORTING MODS:

They are numerous. I'll confine myself to only the stuff I did for safety, reliability and peace of mind while boosted:

• Cooling: TDR's radiator, an FM brushless fan kit with their "fan brain", a Supermiata/Qmax coolant reroute. For oil, I eventually got TDR's dedicated oil cooler with a thermostatic sandwich plate. The car has stayed rock-solid, temp-wise, on both road and track.
• Driveline: FM stage-1 clutch package, miata roadster shifter (seriously just the best thing ever) - that's about it. car already had an LSD.
• Brakes: FM Wilwood LBBC on the front; regular sport brakes in the back (but with stainless lines and new pads). All the whoa I've ever needed - though they did heat up on track and in hindsight I would have changed up to a more track-oriented pad. Super easy with the Wilwoods.
• Data - I got the Innovate PSB-1 boost/AFR combo gauge, which comes with a wideband o2 so it serves as my AFR analogue signal to the ECU as well. Also got their MTX-D oil-pressure and temp combo gauge.
• Air in/burnt gases out: I recently got a Skunk2 64mm throttle body installed - and then of course I broke down and ordered the Skunk2 intake as well. Because it's just so damn pretty. Go ahead, judge me. Also got a Racing Beat header and a full header-back FM stainless exhaust.
• Motor: nothing. Stock motor, 130k. Playing with fire here, I know. Forged internals are on deck for this winter. But for two years it has given me zero issues.

TUNING:

As said, I started with a smaller shop nearby and, while they did great with my old turbo car, they just couldn't get this one to run right. I switched to Drive Auto Sports in Everett WA and they have the car dialed. I bring it to them whenever I change, well, anything to do with fuel, air or spark. Long story short, they ended up getting 265WHP out of this little nugget on their hub dyno. Torque was still down in the 205-210 range, because supercharger - but that does reduce the strain on the internals as well.

DRIVING:

Mentioned my 99 turbo car a couple times, so maybe that's a good comparison point. My first reaction when I got the turbo car back from the shop (I had that kit installed professionally - the TDR kit I did mostly myself) was "holy mother-loving heck, that's a hecking big heck-ball of midrange torque!" (paraphrasing). That was not my reaction, in all honesty, to driving my current car for the first time.

There are a couple of important caveats - the 99 was my first truly "fast" sports car. So it made an impression as only your first time can. Also, in between the 99 and my current 2004, I owned a Porsche 997 turbo. Hard act to follow, especially in the torque department. So you won't be too shocked to hear that driving the TDR car was more, yay this is fun than sweetmaryjesusandjoseph.

That said, it IS fun. Like loads and loads of fun. And it is fast - blisteringly so. You have to learn to drive it differently. It's definitely not a stoplight car (especially where I live, near Seattle, where every other car comes from Fremont CA and runs on electrons. That bored Bellevue housewife next to you can run nines and doesn't even know it). But get it on the back roads, or on a more technical track and dear lord it is the most fun I have ever had on four wheels. The power is linear and smooth. It forces you to stay in the power band, which means a lot of heel-and-toe. But it rewards your practice with sublime corner exits that won't spin you into the Brown Bear parking lot (as my 99 once did when I was not paying attention at a roundabout).

TURBO VS SUPERCHARGER:

The age-old question. I don't have a good answer, I'm afraid. They're just different. The turbo car provided immediate grins as it piled on the torque at mid range and smoked the tires at the slightest provocation. The supercharged car is much more of a fine wine than a vodka and Redbull. She reveals her secrets gradually, and only after some effort - but they are secrets worth knowing. My extremely subjective opinion is that the supercharger is better (and it's not just that I remain bitter about selling the turbo car nearly 6 years later. I mean it's partly that. But still.) - it is so well paired with the car. It feels like a Miata, only more so. If I wanted a torque monster, I'd have gone with a C5 vette (for less money, probably, all-in). But I love this little black Murder Hornet. I love it more every time I climb aboard.

If you want to know anything about my experience, give a shout below and I'll answer to the best of my ability. Thanks for reading my rambling!

Last edited by NB2PNW; 5th December 2023 at 18:56.Reason: Typos and more info