Rover with a turbo, or: How to build a reliable turbo track car. SPM S1, NASA ST3/4
#141
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Late 2016 he asked
"battle of the rule book nerds?
Or battle of the drivers?"
and
"Miatas are very fast, it would become a miata class!!
I have friends with 140whp miatas doing st4 times."
On the face of it, ST should reward cars with intrinsic balance given that all other mods are equalized. Instead of having a wild mix of cars in each class, it should in theory, distill down to the best platforms within each power to weight category. That the NA/NB are killer apps whether they are 16:1 or 8:1 means yeah, they are going to be crushing dreams as they did in PT.
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#142
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Seems like you don't even need to be a rulebook nerd in ST4. PtW cap. Make your car fast any other ways.
I mean I'm sure if you looked hard enough you could find some weird loophole. But its not like PT where there are a million combinations of the same car/same points.
I mean I'm sure if you looked hard enough you could find some weird loophole. But its not like PT where there are a million combinations of the same car/same points.
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Yep. My guess is that his car is wildly underprepped for the class (side mirrors, glass windows, no aero, no powerband tweaks, crappy shocks, minimal setup time, etc etc etc). He was asking "what tires will be popular" a few months ago, so he genuinely has no idea how to set the car up for the class, but he sees a 4-minute video of a competitive car, doesn't understand why his car isn't as fast as mine, and raises hell because he knows he has no chance. Not because the rules give me an advantage (they definitely do not), but because he doesn't want to spend the money or time or effort to be competitive. I'm being nice because we have several mutual friends and I have to race against him, but yeah, he is either Dunning-Kruger ignorant or disingenuous.
Oh well. Everyone I actually talked to at the track loved the car. The TT director in particular said something along the lines of "I'm glad you are giving everyone a target to shoot for" and he seemed to genuinely mean it. Even the guy who finished 2nd to me the entire weekend was ultra-friendly. Typical that the internet is where the crybabies go to air their dirty laundry
Oh well. Everyone I actually talked to at the track loved the car. The TT director in particular said something along the lines of "I'm glad you are giving everyone a target to shoot for" and he seemed to genuinely mean it. Even the guy who finished 2nd to me the entire weekend was ultra-friendly. Typical that the internet is where the crybabies go to air their dirty laundry
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#146
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Couple shots of the V2 ducting going into a customer's S1 build. Single box, sealed up to the radiator, separate box for the IC. Comes up to the mouth and seals there as well. Brake ducts are plumbed into the IC box where they'll get a high-pressure feed instead of trying to suck air from the front of the car.
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Also a pic of an early prototype heat shield. Something similar to this will make it into the full kit later this year.
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Also a pic of an early prototype heat shield. Something similar to this will make it into the full kit later this year.
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#149
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So for those of us following along, is that an OE sized radiator (frontal area)? What's the height of the radiator opening?
Also for my own curiosity, looks like the air dam comes off first with a row of bolts top/bottom, and then the bumper? How long does it take to get it from the assembled state in the 2nd picture to the ducting in the first picture?
Also for my own curiosity, looks like the air dam comes off first with a row of bolts top/bottom, and then the bumper? How long does it take to get it from the assembled state in the 2nd picture to the ducting in the first picture?
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Box is 1/8" ABS sheet and aluminum angle. Bumper can go on as one or two pieces, I typically leave the top part in place and just undo the airdam fasteners, but either one takes ~5min tops.
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And I'm guessing step one in proper ducting like this is ditch the stock cross beam? I see you replaced it in Rover with the grey beam, but it doesn't look like such a beam exists in the above, not needed or is the ducting frame strong enough to replace it?
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When the car actually works, you get to spend time on things like aesthetics.
First up was the flares. They work, but I did not like the bare carbon/kevlar look, and it did not grow on me. So out came the rattlecans. I ordered some real auto-grade spraypaint online, a full primer+base+clear system, along with some good sandpaper and a 3M respirator. $93 for everything.
My goal was to make them turn red. My stretch goal was to make it look the same color with a little layer of dirt on it. The final product exceeded my fairly lofty expectations.
Curing before install, fingers crossed.
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Pretty damn happy with this.
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Upper right is the 2-stage that was applied when the car was resprayed in 2012, lower left is the flare I rattlecanned myself. It might be a couple shades off, but it looks spot on from 3ft.
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Going to pull all the decals later this week and clean it all up, it's been long overdue for a little spit and polish.
![Party Kitty](https://www.miataturbo.net/images/smilies/birthday[1].gif)
First up was the flares. They work, but I did not like the bare carbon/kevlar look, and it did not grow on me. So out came the rattlecans. I ordered some real auto-grade spraypaint online, a full primer+base+clear system, along with some good sandpaper and a 3M respirator. $93 for everything.
My goal was to make them turn red. My stretch goal was to make it look the same color with a little layer of dirt on it. The final product exceeded my fairly lofty expectations.
Curing before install, fingers crossed.
![Name: 2Ft0BKul.jpg
Views: 65
Size: 46.0 KB](https://www.miataturbo.net/attachments/build-threads-57/230493d1683052353-rover-turbo-how-build-reliable-turbo-track-car-spm-s1-nasa-st3-4-2ft0bkul.jpg)
Pretty damn happy with this.
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Upper right is the 2-stage that was applied when the car was resprayed in 2012, lower left is the flare I rattlecanned myself. It might be a couple shades off, but it looks spot on from 3ft.
![Name: AwXJCtZ.jpg
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Going to pull all the decals later this week and clean it all up, it's been long overdue for a little spit and polish.
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Yanked all the decals, gave the car a Mothers R3/Goo Gone bath, and re-stickered. Looks better than it has in a long time. I pulled the dash out late last week, cleaned up the rats' nest of wiring from two different ECU/motor setups, and installed the passenger seat as well.
The quick shorty exhaust I built when I first slapped the car together dumped right under the gas tank, so I finally got around to fixing that as well. No muffler... because racecar.
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Bullet (Emilio's S1) and Rover on the starting grid for Race 1 on Saturday
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Feels like I forgot something
The quick shorty exhaust I built when I first slapped the car together dumped right under the gas tank, so I finally got around to fixing that as well. No muffler... because racecar.
![Party Kitty](https://www.miataturbo.net/images/smilies/birthday[1].gif)
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Bullet (Emilio's S1) and Rover on the starting grid for Race 1 on Saturday
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Feels like I forgot something
![Party Kitty](https://www.miataturbo.net/images/smilies/birthday[1].gif)
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#158
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I don't run sound days at Laguna. I don't particularly like the track as an HPDE course and it's very hard on equipment, so if I want to go, I race with NASA in June when they have their 103dB weekend. Last time I had a Laguna-compliant exhaust on Rover was 2012. I know how to build compliant exhausts, an 18" Magnaflow and a 90deg exit will do the trick down to 90dB, but quiet cars suck.
With the open pipe, it's in the 97-98dB range, still quieter than every Spec Miata out there.
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#159
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I don't run sound days at Laguna. I don't particularly like the track as an HPDE course and it's very hard on equipment, so if I want to go, I race with NASA in June when they have their 103dB weekend. Last time I had a Laguna-compliant exhaust on Rover was 2012. I know how to build compliant exhausts, an 18" Magnaflow and a 90deg exit will do the trick down to 90dB, but quiet cars suck.
With the open pipe, it's in the 97-98dB range, still quieter than every Spec Miata out there.
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--Ian
#160
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MRLS was a blast. I went out for the morning sessions on Sunday and noticed that I had nearly gotten a full clean lap in B with a passenger, so I kicked the passenger out (sorry dude!), turned the camera on, and was able to capture a fairly clean 1:39.4 in full S1 trim. 215whp, 2400lbs, 245/40 Maxxis RC-1s. Stinking fast given the setup. With the holdups in 5 and 11 I'm certain there's a 1:38.9x in the car. The entry speed into T6 scared me so bad I instinctively lifted. ![Party Kitty](https://www.miataturbo.net/images/smilies/birthday[1].gif)
The car ran all weekend with only a couple minor hiccups. I gave a bunch of rides, typically lapping in the 1:41-1:42 range.
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The car ran all weekend with only a couple minor hiccups. I gave a bunch of rides, typically lapping in the 1:41-1:42 range.