bbundy

Here is the stuff I’m still doing wrong according to the list. But some of those things I think I might have been on the pioneering edge of developing and implimenting the answers.

Stuff Miata track turbo guys do wrong

• Pump gas of 92 or lower octane
• OEM Garrett internal wastegate and >10psi instead of VTA
• Throttle plate not epoxied
• No trans cooler
• No diff cooler
• >13psi with NA cam/crank angle sensor + ragged edge tune = det
• No EGT
• RC engineering injectors
• No det cans used during dyno tuning
  

Non-engine stuff done wrong

• Bolt in cage (Actually its a Hard dog roll bar with door bars)
• >2400lb comp weight

[/QUOTE]

bellwilliam

iTrader: (1)

first track day, I wouldn't worry about a thing. nothing on Emilio's list applies..

bellwilliam

iTrader: (1)

Bob:

I would epoxy the throttle plate screw. I've seen 3+ engine went kaboom because of it.

hustler

iTrader: (6)

I'm going home to epoxy my screwz.

bbundy

From what I have seen it is an RPM related thing. Guys frequently over 7200 rpm are the ones braking throttles. one guy here making 170 hp out of a naturally aspirated 1.6l regularly spinning to 8000 rpm is constantly braking throttle plates. I've never broke one. My car is a mid-range torque monster and the torque falls off past 7000 rpm so I shift. He has also broken all sorts of weird stuff due to vibration including the oil pressure sender cracking and falling off the side of the block he is even running stock engine mounts.

Bob

hustler

iTrader: (6)

I'd like to get my track car on a Hall crank sensor, but it's way above my head.

JKav

iTrader: (1)

Happened to our 1.6 ghettocharged lemons car too. The screw head bounced around in cyl #1 for about 20 minutes until it finally shat out through the exhaust valve. Then we ran the engine for another half dozen races. It ran like nothing wrong ever happened.

Then, a couple weekends ago at Buttonwillow, it blew the hell up.

Mind you, the death blow wasn't due to cyl #1. No, it turned out that cyl #3 was pinging like crazy. So much that it eroded the top ringland down to the ring and eroded the head until the head gasket blew. This severe det was not once heard on the dyno (or while racing, which is no surprise - earplugs and helmet). BTW cyl #1 looked like the surface of the moon.

But even cyl #3 wasn't the final nail in the coffin. We kept running it after JB Welding the head & replacing the head gasket. Finally, after a few more hours of racing, cyl #2 punched its rod thru the block. Probably water in the coolant during the head gasket swap resulted in a spun a bearing. Haven't done a postmortem yet.

So, yeah, this just reinforces that these are thrashy, coarse, ping-prone, yet tough little engines.

shuiend

iTrader: (24)

So what you are saying is more JB Weld is the solution?

Seefo

iTrader: (5)

we are already use hall effect cam and crank sensors. At least in the NBs we do?

Gryff

iTrader: (6)

^ NA just has cam sensor.

GeneSplicer

iTrader: (14)

^ yeah - tell me 'bout it not for long though And I thank you for your pain in experiencing that - sure made mine easy to diagnose

240_to_miata

iTrader: (2)

That list was very very depressing.

spoolin2bars

iTrader: (1)

Don't let that list discourage you from the joys of turbo miata power on a track. There's more than 1 way to skin a cat, and many good times can be had without everything on that list.

Seefo

iTrader: (5)

I think that list is more of compilation of things to consider. but it certainly seems like they apply at different stages, rather than on any FI'd miata. Not to mention the list is for a track car. I didn't even know anyone here ran trans/diff. coolers. I would like to read the write-up/discussion on that.

NiklasFalk

iTrader: (1)

I would say that that list is a large (if not huge) collection of wisdom when you really start to push the envelope.
The important thing is to be aware of all the pitfalls and don't be tempted to push too far without monitoring how close to the edge you are. The edge is of course a moving target depending on what things on the list you haven't fixed yet.
A poor tune is of course a problem already at 200whp, but many of the other things are not so critical at that level.

You will get more driving done with a "balanced" car at a decent level than a half-built monster that still have a couple of years in the garage until it's finished.

A noob question that I think is on topic (and might elevate the reliability discussion a bit).
Are there any different concerns sprint vs endurance for a Turbo Miata than for a non-turbo one?
A high strung NA engine must also be decently built to withstand a 24h race but are there anything special to think of for Turbo (that you would not notice in a 30-60 min feature race)?
For argument sake e.g. 110bhp/liter NA vs 200bhp/liter Turbo.

hustler

iTrader: (6)

I don't race my car, but I recently chased a Panoz for about 45-minutes in 103*f heat. Water stayed under 200*f and oil below 235*f, I was really surprised. I also was abel to wring sweat out of my seat-liner, lol. By no means do I think my car would make it through a 6-hour enduro.

I'm somewhat inclined to think that if the engine will survive a 30-minute sprint on the track like we run in TT, the engine will make it through the race. I'd be more concerned with trans and rear end fatigue, brakes at the 12-hour mark, and aside from that I don't have the experience to know much of anything on the subject.

shuiend

iTrader: (24)

They call him Hustler, the man who lives his life a half-hour at a time.

dgmorr

iTrader: (4)

Is it better to use a 99-00 headgasket + reroute when building a new VVT motor? Or do I want to keep the 01+ headgasket with no reroute?


lol +1

shuiend

iTrader: (24)

Go with the 99-00 head gasket and a re-route.

bellwilliam

iTrader: (1)

The list is a collection of all known FI Miata issues. it doesn't mean you need all the mods listed. The list doesn't distinguish between:

150whp turbo or 400whp turbo
20 minutes HPDE or 3 hours race
driver who is 10 seconds above or a driver who is 10 seconds below SM record.

obviously if you are running 150whp turbo in 20 minutes HPDE going 10 seconds slower than SM record, I am sure you do not need ANY of the stuff on the list. On the other hand, if you are Savington in his 350whp, you will need everything on that list to survive a 3 hours enduro race.