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Member Since 23 Jul 2011
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#103688 2001 Honda S2000 - I guess it will be named Crisis...

Posted by Matt93SE on 20 March 2018 - 03:05 PM

Quite impressive that static flow was identical between all 4 injectors both before and after cleaning......

#103555 Competitive Karting: Who has done it?

Posted by Matt93SE on 16 March 2018 - 02:10 PM

Just bumping this thread...  Saw a FB post today that there will be a swap meet at Speedsportz tomorrow (16 Mar 2018) from noon to 6pm..


If anyone is interested in picking up some toys, it sounds like a good place to be.

#103374 Houston trailer/car storage

Posted by Matt93SE on 13 March 2018 - 04:16 PM

At one point I had 8 cars and 3 trailers at my house....   I'm down to 7 cars and 2 trailers.. 


Benefits of living in the country. :)

#103370 Houston trailer/car storage

Posted by Matt93SE on 13 March 2018 - 03:27 PM

HAHA...   I didn't read the date on the thread until I read Robert talking about new house and a Miata..  wait wut?  MIATA?!  When did he get another Miata?!  *check date*   OH. 


#103202 Preventative Maintenance

Posted by Matt93SE on 09 March 2018 - 09:09 AM

On the RX7, I do *some* PM work..  but brakes and rotors?  they last varying lengths of time depending on particular track and weather conditions.  COTA, NOLA, Hallett are all very hard on brakes.  MSRH, not so much.


front wheel bearings get repacked w/ grease every ~3 race weekends.  rear axle bearings get replaced after every 2nd race weekend as they start to fail during the 3rd and if I push it the bearing usually fails on the 4th weekend and it's a smoky DNF.  I'm working on an updated design to use a better bearing, but need a machine shop to make me a custom part.


Front calipers get rebuild once or twice a season, rears about the same.  I usually will do that at the same time I'm doing wheel bearings, since I will have the rotor halfway off and it will be greasy from the bearing process.  might as well make all the mess and get it over with.


Fluids get replaced "when I feel like it"   - usually about once a season based on how much I drive..  That's between 6-10hrs of track time on this car given how much I get it to the track.


Diff fluid tends to get replaced slightly more often because of the rear axle issues and the Miata diff these cars use..   with an RX7 pushing >200whp, the ring and pinion are only marginal in strength.  the good thing is the RX7 has a steel live axle housing and solid axles vs. the Miata's aluminum diff carrier and stub axles.  I think the difference in housing design and live axle helps to keep the ring and pinion alive because of the reduced forces on the axle stubs causing the diff guts to twist and pull..   but this is just my opinion..  RX7s usually don't explode diffs like Miatas do, yet they use the same R&P and put out more power..  

.....  All that said, I've been changing the diff fluid about every 3rd race because of the axle bearing issues. depending on how ugly the bearings look when I pull them out, I get concerned about shrapnel in the fluid and change it.


The 240SX is a completely different story.   It's MUCH more reliable and requires less routine maintenance.   I still change the fluids about once a season due to age, but used to get on track ~20 weekends a year so maybe 40-60hrs of use.  Wheel bearings last for years on it, so there is no scheduled replacement time.  I just keep a spare in the trailer and will swap them between sessions if one starts making noise.  in ~10 yrs of tracking the car, I've had 2 or 3 fail on me.  Brakes are the same way--  I rebuild the calipers when they start to drag at the end of a race/session, and that's usually about once a year based on hours on the car.   I don't keep track of hours because it's so infrequent and easy to do.   none of the issues will cause me to drop out of a race, so they're minor problems. 

Because racecar, I keep spares of everything in plastic bins in the trailer..  wheel hubs, pads, rotors, caliper rebuild kit/ spare rear calipers, spare control arms, tie rods, steering knuckle..   Anything that could get bent and replaced in the pits from a minor collision I have in the trailer.  (fortunately I've never needed them for that purpose.).


Other items like wheel studs and lug nuts--  I again keep spares in the trailer and inspect them when I'm doing other work on the car.  in ~20 years of doing this, I've never had wheel stud failure of any sort.  I've cross-threaded the start of a couple lugnuts when I was in a hurry, and replaced the stud because it was faster than cleaning up the end of the threads.  throw the $1 lug nut away and replace.   takes 30 seconds to pound out and install a new wheel stud and I don't even have to pull the wheel off the car to do it.

#103151 Tech Inspection for DE in Frisco-North Dallas area

Posted by Matt93SE on 08 March 2018 - 07:47 AM

I tried Classic BMW of Plano, but they don’t do inspections for track days.


Kinda ironic since they sponsor, prep, and maintain one of the more successful PWC drivers and cars, and Toby is even listed in their service dept..   you'd think they would be friendly to track cars...  Maybe you just didn't talk to the right person. ;)

#103141 PCA at Hallett - 3/17

Posted by Matt93SE on 07 March 2018 - 02:45 PM

This is nifty...

********New PCA requirement for Driver Education Events********
If your vehicle is equipped with Automatic Emergency Braking Systems, such as automatic braking, or lane assist, please follow the policy as stated. " At this time, it is not known how these systems will react at speed in the HPDE environment. For the safety of all participants PCA has decided not to allow affected vehicles to run with our group at HPDE events unless the system can be and is turned off." This information is listed on the tech sheet.


I wondered if/when/how these electronic nannies would be dealt with for track days/racing..  certainly some testing will be required.   wonder how many sensors these systems have?   Wonder if you can simply unplug a 'sensor head' and disable the system, like they do with wheel speed sensors to disable ABS in some race classes...

Back to the subject..  I love me some Hallett, but can't make it.   Will forward to my dad who runs COMMA up there. he's been jonesing for some practice time.

  • SAD likes this

#103140 Preventative Maintenance

Posted by Matt93SE on 07 March 2018 - 02:19 PM

heh...  I just keep spare "everything" in the trailer..  pads, rotors, wheel bearings, lug studs, etc..   Send it till you see fire, then replace it.

#103081 1992 Acura NSX - Oops, I did it again...

Posted by Matt93SE on 06 March 2018 - 06:41 AM

When we first started using Yokohamas on our WRL car, a tire engineer at Yokohama told me to use a starting pressure of 10 psi for every 100 lbs of car weight as a baseline. Then tweak it from there as needed. That turned out to be very close to what we ended up using. Not sure if that goes for other tire brands also.

I think you're off by a zero. ;)

#103075 1992 Acura NSX - Oops, I did it again...

Posted by Matt93SE on 05 March 2018 - 10:55 PM

Just remember that pressures are very dependent on the car, tire size, weight, alignment, etc. What works for Robert may not work for you. Tire pyrometer is your friend!

#103017 1966 Datsun Roadster Build Thread (Street Car)

Posted by Matt93SE on 02 March 2018 - 03:12 PM


There is hope for this world if there are little girls and boys still interested in cars.

Best way to do that is to be a good steward of the community.  if someone's showing an interest in my car (particularly kids), I take the time to talk to them and answer questions..  if they're kids and I have time, I let them climb in the car and push buttons/switches etc after I secure the fire bottle.  To me it's just a basically stock car that's gutted with a cage and some gauges, but to them it's a full-on race car- it could be an F1 car and I'm Schumi for all they care.


But yeah..  watching people light up when they see your car is always cool.  Every time I took dad's old 63 1/2 Galaxie out, there was always a story or a comment I'd get from older adults who knew what they were, the kids just thought it was a huge old car but still loved it.

#103012 1999 Lexus SC400 - I messed up good this time

Posted by Matt93SE on 02 March 2018 - 10:38 AM

After this much practice, you should be able to drop that tranny in 20 min! :P

#102707 Fixed vs Floating Hats

Posted by Matt93SE on 16 February 2018 - 09:45 AM

floating rotors are preferred for a high heat application, but are more expensive since the slots/obround holes require more machining than a simple 5/16" hole.  The hardware is also a bit more expensive and wears out.  So add another $200 every rotor change (maybe every other change?) for new hardware.  12-pack of t-locks are ~$50, and screws/drive bobbins are another $60.  so that's $110/rotor for mounting hardware.




I've never bothered to fork out the money for a floating setup, and have had no problems with wheel bearings or rotor longevity with fixed mount rotors using 5/16" safety wire bolts.




I replace the bolts every 2-3 rotor changes- basically when they get old enough the threads start getting rusty and risk stripping the holes in the mounting hat or rotor..  the strength of these bolts is more than high enough that they are never really fatigued under the loads presented in these conditions.  (shear strength of a single 5/16" grade 8 bolt is about 5700lbs. with 8,10,12,16 bolts per rotor?  yeaahhh.)

#102695 Hearing Protection Recommendations?

Posted by Matt93SE on 15 February 2018 - 08:22 AM

This is the cheapo custom solution that I went with.  It's treated me well.




Just mix the materials, stick them in your ear, let them harden, and voila, fancy custom earbuds for less than 40 bucks shipped.

Not once do I see a specification/rating for noise reduction on that site...........

#102533 Would anyone be interested in running laps at TWS or MSR Cresson on Assetto C...

Posted by Matt93SE on 08 February 2018 - 09:51 AM

....Log onto TJ..
.... click 'view new content'
... See thread starting with "Would anyone be interested in running laps at TWS"

Gotta say my heart skipped a beat or two.