Rover with a turbo, or: How to build a reliable turbo track car. SPM S1, NASA ST3/4
12-11-2018, 12:19 PM
#181
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Yes, 175*F thermal bulb on the bottle. Will mount the bottle somewhere in the cabin, probably under the rear window.
New cage pics, picking it up from TC Design this afternoon. Rover's rear-half was done by TC sometime last decade, before I owned the car. I had Tony add the front half in 2011 after the initial N/A VVT build, but a basic Spec Miata cage isn't quite up to snuff for the pace of this car anymore.
Gone are the NASCAR bars in lieu of a GT3 Cup-style triangle bar with attachments to the rocker sill on both sides. These are gusseted in the center and they attach far higher up on the cage as opposed to the old bars. The A-pillar bar is now doubled up, along with a large gusset above that to support the bend in the A-pillar bar. This is a big improvement to frontal crash protection.
From the top of the new door bar, there's a second attachment from the cage to the firewall, coming into the same OEM gusset which transfers load from the main frame rails, as well as a new gusset at the top of the windshield.
OEM dash bar is deleted, curved cage dash bar is replaced with a gusseted straight bar. New roof bar as well (this is now standard in his SM cages but it wasn't in 2010).
Picking up today. This interior is still wearing the original 30-year old "coat" of SU Classic Red, so the plan is to do a fresh coat of gloss white.
New cage pics, picking it up from TC Design this afternoon. Rover's rear-half was done by TC sometime last decade, before I owned the car. I had Tony add the front half in 2011 after the initial N/A VVT build, but a basic Spec Miata cage isn't quite up to snuff for the pace of this car anymore.
Gone are the NASCAR bars in lieu of a GT3 Cup-style triangle bar with attachments to the rocker sill on both sides. These are gusseted in the center and they attach far higher up on the cage as opposed to the old bars. The A-pillar bar is now doubled up, along with a large gusset above that to support the bend in the A-pillar bar. This is a big improvement to frontal crash protection.
From the top of the new door bar, there's a second attachment from the cage to the firewall, coming into the same OEM gusset which transfers load from the main frame rails, as well as a new gusset at the top of the windshield.
OEM dash bar is deleted, curved cage dash bar is replaced with a gusseted straight bar. New roof bar as well (this is now standard in his SM cages but it wasn't in 2010).
Picking up today. This interior is still wearing the original 30-year old "coat" of SU Classic Red, so the plan is to do a fresh coat of gloss white.
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03-20-2019, 04:27 PM
#185
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Completely missed the recap for Buttonwillow apparently. 
We had a great field, 6 cars in S1. The cage updates in Rover dramatically stiffened the chassis, with extra attachments at the firewall, windshield header, rocker panels, and seatbelt towers, so much so that I was unable to tune out the push it created. The car now feels completely solid on track, despite the ~250,000 total miles on the shell, at least 20% of which are on track.
New interior is much brighter and nicer. No more dash, for now. The center switch panel is partially populated, it will change again soon as well.
My race 4 was cut short by a failed wheel bearing, the same one that was replaced after the Sonoma event back in September, which really annoyed me. I don't recall striking or bumping that wheel on anything this time around. I was quite happy to get the OEM hubs off the car entirely. I joined the MiataHubs train in November and they finally arrived after Buttonwillow.
Having put some hours on these, I can't say enough good things. They survived a monster curb strike on Sunday that bent two of my 6ULs pretty badly (the LR is over an inch out of round), and as an unexpected bonus, the knockback issues I've been chasing since adding the Superlite kit are gone. Completely eradicated, even after rattling the car over exit curbs and such. IMO, they are a must-have if you're building a car of this caliber.
Before Chuckwalla, I also made some big updates to the suspension, swapping the 1000/550s for 1100/600 and swapping the stock 11mm rear bar for a Supermiata 14mm bar. I always felt the car was a hair tight and I was compensating with a bunch of rake, but the cage made it a lot worse, so I took a big step towards freeing up the car. Ride heights stayed mostly the same, I pulled 3 turns out of the rear that I had added at Buttonwillow in an attempt to free the car up. It worked very nicely, I ended up going to the middle position on the 14mm bar and adding one click of wing and the car is totally dialed once again. The 1100s and cage upgrade have brought a level of stability and sure-footedness that I haven't experienced in another Miata before. It changes direction NOW, whenever you want, exactly as much as you want, but it's still forgiving if you goof up an apex or turn in a little early or late. It's so nice. So, so nice.
Also added an OS Giken back into the mix. These are legal for S1 for 2019. We had originally opted to go to a 3.636 R&P as well, but Emilio tried that at Buttonwillow and said it was no bueno at all. We made a snap decision to keep the 3.9s, so I had three sets built up for myself and two other S1 customers. I thought this was a cool picture - about $6k in diff hardware just hanging out.
Chuckwalla was the first 70+deg event of the year, so I also re-installed my coolsuit and finally (FINALLY) got some real ducting into Rover. Same .050" aluminum ducting theory as the other cars I've posted pics of, just slightly tweaked to fit the oddball proto config that Rover has. I never say anything north of 195*F the entire weekend. I also, finally, screened the radiator. The IC and rad in this car are pretty beat up and will likely need to be replaced at some point, when I get to it, so maybe in 2021.
Fast lap. Went out on sticker RC1s in the cool air on Sunday morning and set a flyer. We were going about 2 seconds a lap slower than this in the wind/heat just 3 hours later.
Next event in 3 weeks at Willow Springs, then NASA in 4 weeks at Thunderhill. Can't wait to get on some R7s again.
We had a great field, 6 cars in S1. The cage updates in Rover dramatically stiffened the chassis, with extra attachments at the firewall, windshield header, rocker panels, and seatbelt towers, so much so that I was unable to tune out the push it created. The car now feels completely solid on track, despite the ~250,000 total miles on the shell, at least 20% of which are on track.New interior is much brighter and nicer. No more dash, for now. The center switch panel is partially populated, it will change again soon as well.
My race 4 was cut short by a failed wheel bearing, the same one that was replaced after the Sonoma event back in September, which really annoyed me. I don't recall striking or bumping that wheel on anything this time around. I was quite happy to get the OEM hubs off the car entirely. I joined the MiataHubs train in November and they finally arrived after Buttonwillow.
Having put some hours on these, I can't say enough good things. They survived a monster curb strike on Sunday that bent two of my 6ULs pretty badly (the LR is over an inch out of round), and as an unexpected bonus, the knockback issues I've been chasing since adding the Superlite kit are gone. Completely eradicated, even after rattling the car over exit curbs and such. IMO, they are a must-have if you're building a car of this caliber.
Before Chuckwalla, I also made some big updates to the suspension, swapping the 1000/550s for 1100/600 and swapping the stock 11mm rear bar for a Supermiata 14mm bar. I always felt the car was a hair tight and I was compensating with a bunch of rake, but the cage made it a lot worse, so I took a big step towards freeing up the car. Ride heights stayed mostly the same, I pulled 3 turns out of the rear that I had added at Buttonwillow in an attempt to free the car up. It worked very nicely, I ended up going to the middle position on the 14mm bar and adding one click of wing and the car is totally dialed once again. The 1100s and cage upgrade have brought a level of stability and sure-footedness that I haven't experienced in another Miata before. It changes direction NOW, whenever you want, exactly as much as you want, but it's still forgiving if you goof up an apex or turn in a little early or late. It's so nice. So, so nice.
Also added an OS Giken back into the mix. These are legal for S1 for 2019. We had originally opted to go to a 3.636 R&P as well, but Emilio tried that at Buttonwillow and said it was no bueno at all. We made a snap decision to keep the 3.9s, so I had three sets built up for myself and two other S1 customers. I thought this was a cool picture - about $6k in diff hardware just hanging out.
Chuckwalla was the first 70+deg event of the year, so I also re-installed my coolsuit and finally (FINALLY) got some real ducting into Rover. Same .050" aluminum ducting theory as the other cars I've posted pics of, just slightly tweaked to fit the oddball proto config that Rover has. I never say anything north of 195*F the entire weekend. I also, finally, screened the radiator. The IC and rad in this car are pretty beat up and will likely need to be replaced at some point, when I get to it, so maybe in 2021.
Fast lap. Went out on sticker RC1s in the cool air on Sunday morning and set a flyer. We were going about 2 seconds a lap slower than this in the wind/heat just 3 hours later.
Next event in 3 weeks at Willow Springs, then NASA in 4 weeks at Thunderhill. Can't wait to get on some R7s again.
Last edited by Savington; 03-20-2019 at 04:52 PM.
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04-09-2019, 08:37 PM
#187
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Great day at WSIR. I don't get here often and it always spooks me first session. There's fast, and there's fast, and this is fast. T8 is so damn bumpy that I am barely flat through it, and T9 is now really, really properly fast. The S2 cars only get through there in the mid 90s, but due to the speeds, the S2s can get past the apex at 105+ with a 1.9g peak load. Insane.
Car was flawless all day. I started hearing a chirping noise on off-idle throttle application midway through the day, which traced back to the BPV vac hose which must have gotten into the accessory belt at some point. A new hose and off we go.
WSIR hot lap video:
3 days at Thunderhill later this week, including my first ST4 race in a couple of years. Looking forward to some purple goodness
Car was flawless all day. I started hearing a chirping noise on off-idle throttle application midway through the day, which traced back to the BPV vac hose which must have gotten into the accessory belt at some point. A new hose and off we go.
WSIR hot lap video:
3 days at Thunderhill later this week, including my first ST4 race in a couple of years. Looking forward to some purple goodness
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05-08-2019, 01:10 AM
#188
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Time for my monthly update.
ST4 in Norcal has exploded, with 16 cars in the class for Saturday/Sunday at Thunderhill. It's mostly S5x-powered BMWs with a couple of S2000s, a Rotrex'd FRS, and myself. I qualified P2 Saturday and motored the pole sitter at the start, but got nearly driven into a couple of laps in by another driver, who was DQ'd for reckless/dangerous after the race director reviewed video footage from the polesitter's car. I solo-spun shortly after the divebomb and ended up 7th. Sunday went a little better, I qualified 4th, slipped to 5th at the start, and then waited for traffic and my tires to come in. Ended up 2nd. P1 both days was an S54-powered E46 sedan which is the class of the field, he had a full second on every other car both days. Well-prepped car and well-driven. It will take some thought and perhaps a Teves MK60 system to get closer to him.
I was pleasantly surprised to discover that running the car so heavy has finally gotten me to the point where I have enough power to keep up with the heavier (but larger) M3s. My NASA mapping is 215whp average, 2495lbs. Peak power is 211whp, with 205whp+ from 4700 to 7500rpm. The new NASA rules which require us to jump through all sorts of hoops to submit a dyno chart appear to have done ****-all to prevent that sort of powerband, as every fast car in the field has a similar flat powerband.
I was struggling with axle tramp exiting T11 both days, which I traced back to worn polyurethane bushings in the lower rear control arm. They were swapped with ISC Delrin in that position before Sonoma this past weekend, and all of the toe play in the rear end is gone, with much more feel coming through the chassis from the rear tires now. The old bushings were so worn out that they all but fell out of the arms, and they feel soft like rubber. It makes me wonder about the rest of the bushings in the car. Those ES bushings were installed in 2010, so they're probably all due for replacement.
I also know that the rear upper arm could be strengthened or replace to help with this issue, but I don't like either of the current aftermarket options (Paco or V8R), so I'm resisting that change for now. The Delrin lower bushings seem to have made a huge difference, so we'll stick with that for now.
I also grenaded another 6-speed at the beginning of the 2nd session on Sunday at Sonoma. This one went into the car at MRLS, with only ~27hrs of runtime since then, but it was also quite unhealthy from day one (3/4 fork was tweaked, crunchy 5th, etc). I have a healthy MSM box to replace it which I hope to get at least a year or two (50-100hrs) from.
I have an open test at Sonoma in about a week, and then NASA there in a week and a half. The tighter track should play to my strengths in that class.
ST4 in Norcal has exploded, with 16 cars in the class for Saturday/Sunday at Thunderhill. It's mostly S5x-powered BMWs with a couple of S2000s, a Rotrex'd FRS, and myself. I qualified P2 Saturday and motored the pole sitter at the start, but got nearly driven into a couple of laps in by another driver, who was DQ'd for reckless/dangerous after the race director reviewed video footage from the polesitter's car. I solo-spun shortly after the divebomb and ended up 7th. Sunday went a little better, I qualified 4th, slipped to 5th at the start, and then waited for traffic and my tires to come in. Ended up 2nd. P1 both days was an S54-powered E46 sedan which is the class of the field, he had a full second on every other car both days. Well-prepped car and well-driven. It will take some thought and perhaps a Teves MK60 system to get closer to him.
I was pleasantly surprised to discover that running the car so heavy has finally gotten me to the point where I have enough power to keep up with the heavier (but larger) M3s. My NASA mapping is 215whp average, 2495lbs. Peak power is 211whp, with 205whp+ from 4700 to 7500rpm. The new NASA rules which require us to jump through all sorts of hoops to submit a dyno chart appear to have done ****-all to prevent that sort of powerband, as every fast car in the field has a similar flat powerband.
I was struggling with axle tramp exiting T11 both days, which I traced back to worn polyurethane bushings in the lower rear control arm. They were swapped with ISC Delrin in that position before Sonoma this past weekend, and all of the toe play in the rear end is gone, with much more feel coming through the chassis from the rear tires now. The old bushings were so worn out that they all but fell out of the arms, and they feel soft like rubber. It makes me wonder about the rest of the bushings in the car. Those ES bushings were installed in 2010, so they're probably all due for replacement.
I also know that the rear upper arm could be strengthened or replace to help with this issue, but I don't like either of the current aftermarket options (Paco or V8R), so I'm resisting that change for now. The Delrin lower bushings seem to have made a huge difference, so we'll stick with that for now.
I also grenaded another 6-speed at the beginning of the 2nd session on Sunday at Sonoma. This one went into the car at MRLS, with only ~27hrs of runtime since then, but it was also quite unhealthy from day one (3/4 fork was tweaked, crunchy 5th, etc). I have a healthy MSM box to replace it which I hope to get at least a year or two (50-100hrs) from.
I have an open test at Sonoma in about a week, and then NASA there in a week and a half. The tighter track should play to my strengths in that class.
Last edited by Savington; 05-08-2019 at 01:25 AM.
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05-13-2019, 08:17 PM
#189
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I am in the market for a known good, low mileage MSM 6-speed. Willing to pay top dollar for it. I am sick and tired of shitty, grindy, notchy 6-speeds. I know nice ones are out there.
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05-14-2019, 07:40 AM
#192
I highly recommend a trans from Walter Motorsports, there may be a lead time now that others have discovered them, but well worth it. You could use this last "known good" and subsequent POS box to send in for a rebuild core
Last edited by slammed200; 05-14-2019 at 03:47 PM.
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