I've done gears, R&P, synchros, clutch disc, LSD plates, pistons, rings, main & rod bearings, etc...
RYU's "properly molested" NSX build thread
- Thread starter RYU
- Start date
I got my coilovers back from Feels last weekend. Thanks Heart2hateu for helping me get them done! I'm now in the process of ordering another set of 9k springs for the rear to test out a 9k/9k setup since my rear dampers are now revalved to 9k.
So now continues my unexpected rebuild program. The OE bumpstops that came with the DG5 are worn and require replacement. According to one of DG5s blogs Tsuchiya spent 1-2 days strictly tuning for bumpstops. I'm now falling into the abyss of learning just enough to properly replace my set. I know bumpstop tuning can get quite complicated. Since I have no way to measure the stiffness of the OEM DG5s bumpstops I feel like learning this from scratch so I can order an appropriate bumpstop replacement... Yay for me.......................
Fat Cat has some educational videos on bumpstop tuning for Miatas if anyone is interested.
https://www.youtube.com/playlist?list=PL75DC8BAD62876251
So now continues my unexpected rebuild program. The OE bumpstops that came with the DG5 are worn and require replacement. According to one of DG5s blogs Tsuchiya spent 1-2 days strictly tuning for bumpstops. I'm now falling into the abyss of learning just enough to properly replace my set. I know bumpstop tuning can get quite complicated. Since I have no way to measure the stiffness of the OEM DG5s bumpstops I feel like learning this from scratch so I can order an appropriate bumpstop replacement... Yay for me.......................
Fat Cat has some educational videos on bumpstop tuning for Miatas if anyone is interested.
https://www.youtube.com/playlist?list=PL75DC8BAD62876251
Something I'd like to install before this summers track season. These the phenolic gaskets that ASM sells. He custom built the autorotor center plate for me with provisions for a spray nozzle post blower.
It will have to wait since the car is getting the DF wide front fenders installed and I'm waiting on my OS Giken clutch to come in
Hi Ryu,
Did you install the ASM phenolic gaskets already?
Last weekend I picked up my NSX with just the basis ASM gasket (between engine en intake manifold) installed.
I also had a Zeitronix boost en IAT-sensor installed (in the bottom of the manifold) so I can read the data from there.
So far, even after about an hour of driving, and going into boost a couple of times, the IAT has not exceeded 158 Fahrenheit yet.
When driving at around 80 mph, IAT sits at around 110-115 Fahrenheit.
Am not sure what would be normal but would like to know what kind of results you are getting.
What was ambient temperature?
At those temps with that kind of relatively easy driving heat soak wasn't a big issue.
Regan, you're moving away from Tsuchiya's tune with the re-valve and the softer springs. I would try to get the bumpstops to match your current tune rather than replicate his at this point.
BTW, my BC's now have 6 track days on them and the 10/8 swift combo is great (Comptech F/R sways 0.75"). I may have Feals rebuild them when they finally go.
I haven't retuned the fronts (yet) and wanted to find a slightly longer and progressive bump stop. I've seen 2 versions of the DG5 and each set uses different bumpstops. I'm just trying to learn more about it so I can made modifications with some understanding of the ramifications.
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BTW...the rears show no bump stop wear at all... So not an issue there but perhaps with the softer springs it will be...
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BTW...the rears show no bump stop wear at all... So not an issue there but perhaps with the softer springs it will be...
Analysis paralysis... I was hoping this year would be a high seat time year but its not turning out that way.
I wouldn't get too worked up or concerned about the bump stops. Yes there are cars (like the V8 M3) which are designed with spring rates and travels calculated to use the bump stops in cornering but for most purposes, being on the bumpstops creates a harsh ride which is bad for ride quality and compliance and predictability on track.
If you look at Video 2, about 1:30 into the video you'l see graphs of a stock (black) miata bump stop that is much longer and stiffer than the ones he sells:
The shorter and softer bump stops allow the spring to have more travel at its given rate before the bump stops ramp up to infinity, but the 'knee' where you first touch the bumpstop until its buried with a infinite spring rate is fairly short. Yes you can use this to tune a car at the limit but short of highly advanced methodological testing and equipment, it's mostly a waste of time.
Most coilovers have a shorter damper body which increases bump travel, and KW's are designed with proper (shorter) bump stops, and we really aren't worried about the NSX bottoming out the chassis on track, so the only real advantage of bumpstops are reducing travel to prevent the tire from rubbing the inner fender well -at the expense of ride quality and compliance on track.
Ideally you want to run the car as low as possible without hitting the bumpstops. You can do this by getting softer/shorter bump stops or cutting yours down. Staying off the bump stops will result in more grip, a more predictable and comfortable ride.
0.02
Lol. Bump steer is totally different than bump stop 
Considering buying this bumpstop kit. It's on the soft side and tall at 46mm. The thought was I could cut it down if needed. These mofos are expensive!
http://www.good-win-racing.com/Mazda-Performance-Part/61-0790.html
I changed the pilot bearing. It was a tight fit so I heated up the flywheel and it slid in with just a little bit of persuasion.
Here's the clutch installed. Very impressed with this product. The pedal feel is consistent and a bit softer than stock. I also liked the push alteration kit. I didn't have to screw around with the fork alignment. BTW... the OSG clutch kit doesn't come with an alignment tool.
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Also... the pressure plate bolt tightening sequence is a tedious process. Make sure you do it right and take your time. It's very important to the proper operation of the clutch discs. It took me a long time and had to do it twice because I had first not had the inner clutch disc aligned properly. Didn't push the alignment tool far enough. Rookie mistake!
http://www.good-win-racing.com/Mazda-Performance-Part/61-0790.html
I changed the pilot bearing. It was a tight fit so I heated up the flywheel and it slid in with just a little bit of persuasion.
Here's the clutch installed. Very impressed with this product. The pedal feel is consistent and a bit softer than stock. I also liked the push alteration kit. I didn't have to screw around with the fork alignment. BTW... the OSG clutch kit doesn't come with an alignment tool.
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Also... the pressure plate bolt tightening sequence is a tedious process. Make sure you do it right and take your time. It's very important to the proper operation of the clutch discs. It took me a long time and had to do it twice because I had first not had the inner clutch disc aligned properly. Didn't push the alignment tool far enough. Rookie mistake!
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Are they 18x8.5 +42 wheels with a 10mm spacer to effectively have a +32 offset?I'm hot and cold on the DF fenders. I love that they now allow me more tire options (and this was the main reason for them). I love that they don't have the front sidemarker. I don't like that they have the more pronounced tire well crease and I don't like that they're FRP. You'll notice that crease in the photo next to the Ariel Atom above. Overall I'm glad I got them. Even if I wreck these I won't feel so bad. I already wrecked an OEM fender with 235s before. Can't run 235s on an aggressive offset AT ALL and with BBK the wheel options becomes very limited.
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Yes, I have 18x8.5 +32 (10mm H&R spacer and extended lugs installed to clear the caliper)
This is on a 215 tire so you'll notice the stretch. There's plenty of room.
You are correct.
The only variance that is an "unknown" is how thick my BBK rotor hubs are as compared to stock. I suspect a +/- 3mm variance there.
Have any more pics of that setup from different angles to see wheel-fender clearance?
What's the offset of your current (17x8?) front 235/40-17?
What's the offset of your current (17x8?) front 235/40-17?
EDIT BELOW. It's 15mm not 10mm.
I don't have any more pics of the 18s but I have one more pic of the 17s below.
Volk Racing CE28n High Pad
Front: 17x8 +38 Rear: 18x9.5 +40
In this picture I have a 20mm spacer in the rear and a 15mm spacer in the front. I was testing out the max limits of rubbing of the 275s and 235s in preparation for wheels. These rubbed but was still somewhat driveable. Not a track setup at all, but best left to the car show hellaflush guys. They'd be ok with this kind of wheel rub.
I don't have any more pics of the 18s but I have one more pic of the 17s below.
Volk Racing CE28n High Pad
Front: 17x8 +38 Rear: 18x9.5 +40
In this picture I have a 20mm spacer in the rear and a 15mm spacer in the front. I was testing out the max limits of rubbing of the 275s and 235s in preparation for wheels. These rubbed but was still somewhat driveable. Not a track setup at all, but best left to the car show hellaflush guys. They'd be ok with this kind of wheel rub.
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Did the fronts rub in which pic or comment? I lost your point of reference.
In that overhead pic with Willem's car I'm running the same CEs and the same tire BUT no spacer. Totally fine if you remove the fender liner. I had to grind down one of the fender liners retaining tabs on the df fender so it wouldn't rub. I don't see how one can keep those tabs and not rub...
In that overhead pic with Willem's car I'm running the same CEs and the same tire BUT no spacer. Totally fine if you remove the fender liner. I had to grind down one of the fender liners retaining tabs on the df fender so it wouldn't rub. I don't see how one can keep those tabs and not rub...
Recieved my bumpstops today. I'll need to cut these down...
You answered the question in email if they rubbed with the spacers. Are you saying they'll rub the tabs if you don't grind them down without the spacer?
Cut the fat base of the bump stop down to atleast match your old bumpstop.
Cut the fat base of the bump stop down to atleast match your old bumpstop.
I'll call you within the next 2hrs Billy.
