Ian's 99 build thread
08-05-2017, 11:28 PM
#1041
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Join Date: Mar 2007
Location: Santa Clara, CA
Posts: 5,165
Total Cats: 855
Took a close look at the broken power steering line today to see if I could figure out how it failed. Turns out that it cracked the hard line at the top, where it's connected to the banjo fiting.
So yeah, support bracket failed and shortly thereafter it did that.
--Ian
So yeah, support bracket failed and shortly thereafter it did that.
--Ian
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08-24-2017, 01:23 PM
#1042
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Join Date: Mar 2007
Location: Santa Clara, CA
Posts: 5,165
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So I took the Miata to Laguna Seca with CFRA on Monday, things went well. The power steering behaved itself, and the fix to the fuel starvation thing seems to have worked. On two occasions I was able to run it down to less than 1/3 of a tank without noticing any stumbling, and reviewing the data logs it looks good there as well.
Here's some video+data from the end of one of those sessions, going through turn 5 there was no loss of power and you can see the fuel pressure and MAP are moving in unison. Don't read too much into the actual number there, it doesn't match up with what it's supposed to be, and I think there's a unit conversion happening incorrectly somewhere in the data pipeline, but it's not falling off under cornering/acceleration the way that it was before.
(argh, embedded youtube doesn't seem to be able to take a time offset, so I'm just going to use a link)
https://www.youtube.com/watch?v=vGEiSnDTcRI#t=19m25s
This set of RRs are done, they've still got tread left but they're barely pulling 1.0g in the corners whereas they'll do 1.3+ when they're new. Still trying to work on my "braking too much" problem, but with only minor success. It may be time to seek professional help.
--Ian
Here's some video+data from the end of one of those sessions, going through turn 5 there was no loss of power and you can see the fuel pressure and MAP are moving in unison. Don't read too much into the actual number there, it doesn't match up with what it's supposed to be, and I think there's a unit conversion happening incorrectly somewhere in the data pipeline, but it's not falling off under cornering/acceleration the way that it was before.
(argh, embedded youtube doesn't seem to be able to take a time offset, so I'm just going to use a link)
https://www.youtube.com/watch?v=vGEiSnDTcRI#t=19m25s
This set of RRs are done, they've still got tread left but they're barely pulling 1.0g in the corners whereas they'll do 1.3+ when they're new. Still trying to work on my "braking too much" problem, but with only minor success. It may be time to seek professional help.
--Ian
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09-05-2017, 03:41 AM
#1047
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Join Date: Mar 2007
Location: Santa Clara, CA
Posts: 5,165
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No Miata news, but a few months ago I ordered the Ohlins R&T kit for the FD. It was back-ordered, but apparently a container arrived a couple weeks ago, and mine were on it:
Sexy:
Ride height is fixed:
(lots more photos in my FD build thread on GRM here: https://grassrootsmotorsports.com/fo.../123739/page3/)
--Ian
Sexy:
Ride height is fixed:
(lots more photos in my FD build thread on GRM here: https://grassrootsmotorsports.com/fo.../123739/page3/)
--Ian
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09-05-2017, 02:33 PM
#1049
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I haven't aligned it yet, so I haven't really pushed it around any corners.
On the short drive to dinner it felt great. I was worried that going 4x on the stock spring rates would make it really punishing, but it's very reasonable.
--Ian
On the short drive to dinner it felt great. I was worried that going 4x on the stock spring rates would make it really punishing, but it's very reasonable.
--Ian
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09-06-2017, 04:52 PM
#1051
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Join Date: Sep 2014
Posts: 21
Total Cats: 5
I drove it for about fifteen minutes. It was just some expressway driving with a bit of wiggling the wheel to see how quickly it wanted to answer, some brake stabs, and a couple corners at moderate speed. This was a shakedown run so we weren't pushing it hard.
Previously the car was sprung pretty soft but very well composed, like a good GT. There was a lot of body movement but it would respond very predictably.
After the change, squat, dive, and roll are now firmly in check. The transitions are faster. It still has perfect manners on turn in, and when going over lumps in the road.
I notice every little crack in the pavement. They're not jarring at all, but I'm aware of each one in a good way: it feels in touch with the road.
The recommended settings from Ohlins feel cleanly damped and comfortable. It sits about 25mm lower. In my opinion it looks great. There's plenty of clearance to get it on the lift, go over speed bumps, and pull out of driveways without any trouble. With the higher spring rates it has enough suspension travel and I never noticed it hitting the bump stops.
It's what I'd call "road sport". It's just right for spending an hour on twisty mountain roads, but still supple enough that you won't regret it if you decide to go a couple hours more. It improves everything a car of this class is supposed to do well.
I'm eager to see how it does once it's aligned and run hard.
Previously the car was sprung pretty soft but very well composed, like a good GT. There was a lot of body movement but it would respond very predictably.
After the change, squat, dive, and roll are now firmly in check. The transitions are faster. It still has perfect manners on turn in, and when going over lumps in the road.
I notice every little crack in the pavement. They're not jarring at all, but I'm aware of each one in a good way: it feels in touch with the road.
The recommended settings from Ohlins feel cleanly damped and comfortable. It sits about 25mm lower. In my opinion it looks great. There's plenty of clearance to get it on the lift, go over speed bumps, and pull out of driveways without any trouble. With the higher spring rates it has enough suspension travel and I never noticed it hitting the bump stops.
It's what I'd call "road sport". It's just right for spending an hour on twisty mountain roads, but still supple enough that you won't regret it if you decide to go a couple hours more. It improves everything a car of this class is supposed to do well.
I'm eager to see how it does once it's aligned and run hard.
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09-11-2017, 11:18 AM
#1053
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Join Date: Mar 2007
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So last weekend was time for the biennial regulatory teardown and inspection opportunity. The turbo manifold wouldn't come off, it's warped enough to close up the relief cuts through the bolts holes on the bottom. I guess I got this a little hot. We managed to get it off by hammering chisels into the tops of the relief cuts to wedge them open, then pulling really hard.
A straightedge and a feeler gauge showed about 5 thou of gap at the worst spot, so something needs to be fixed before it goes back on for Miatas@MRLS. At a minimum it needs resurfacing, the relief cuts being opened up, and the stud holes enlarged to the outside by a couple mm. It may just need to be replaced -- i'm not sure.
--Ian
A straightedge and a feeler gauge showed about 5 thou of gap at the worst spot, so something needs to be fixed before it goes back on for Miatas@MRLS. At a minimum it needs resurfacing, the relief cuts being opened up, and the stud holes enlarged to the outside by a couple mm. It may just need to be replaced -- i'm not sure.
--Ian
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09-11-2017, 11:42 AM
#1055
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No.
1) I have 3 weekend days free between now and Miatas@MRLS. No time.
2) I don't really want to spend $3K+ on a new turbo set up
3) My exhaust won't bolt to it
4) I'd lose my EWG, and I really like that for boost control
5) the 400-ish RPM of spool I'd gain (comparing my dynos to some TSE/EFR ones I've seen) isn't very significant on the track, the car is basically never below 3500 RPM so it just doesn't matter.
If I were starting from scratch I'd seriously consider a TSE setup, but it doesn't make sense to ditch what I have.
--Ian
1) I have 3 weekend days free between now and Miatas@MRLS. No time.
2) I don't really want to spend $3K+ on a new turbo set up
3) My exhaust won't bolt to it
4) I'd lose my EWG, and I really like that for boost control
5) the 400-ish RPM of spool I'd gain (comparing my dynos to some TSE/EFR ones I've seen) isn't very significant on the track, the car is basically never below 3500 RPM so it just doesn't matter.
If I were starting from scratch I'd seriously consider a TSE setup, but it doesn't make sense to ditch what I have.
--Ian
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09-11-2017, 03:47 PM
#1058
That casting will not warp much after that initial big warping you had, re surface it and make the track day.
just as a datta point Bridgeport would rough machine their castings and leave them out side in the hot summers and frizing temperatures for 5 years before final machining to avoid the warping that castings go through.
just as a datta point Bridgeport would rough machine their castings and leave them out side in the hot summers and frizing temperatures for 5 years before final machining to avoid the warping that castings go through.
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