doward

I don't see what was more convenient. You were already spending time and money on the dyno and you don't need a fresh dyno sheet every time to swap tires. I switched between SM6 and R7 this year too by just handing in paperwork.

Regardless, If you were sub 17.5:1, you were in a good spot.

Quantification is extremely hard, yes.

whoahstu

The difference or hassle is the room in horsepower or weight that the reclass cars need to leave for a buffer. I've read whole threads and conversations on how much room to leave; 2,3,5 hp, etc. There's a lot of extra wt/pw leaving a large buffer. I cannot adjust with maps like those with an ECU upgrade. The reclass would give me more weight and having to worry about going over on power. Anyone ever pop a dyno?

flier129

iTrader: (7)

Sooo...... I should feel better about my driving being within 1 second of the track records running 18.5lbs:1hp (2410/130) ?

doward

.......

doward

Time to don our tin foil hats...

A Miata won PTE and PTD at both championships, plus PTC at western.
A Miata won TTE, TTD and 2nd in TTB at western, 2nd place in Eastern D and E.

bellwilliam

iTrader: (1)

if I were Greg, I would start a PTM (PT Miata).......less whining for all !!

charliehayes22

Good weekend. Fun hanging with Dan and Megan and some of my old racing buddies. Car was good out of the box was really quick on 1ccw. Made a few rear damper changes, 1 hole soft on the rear ARB, tried some less wing but lost some grip that was more delta than any mph in the straights. Toyo RRs were new warm up on Friday ran qual and both heats with 1 set. Set 2 ran Saturday warm up to scuff, TT on Sunday and the Main on Sunday. Never had any degradation. Could run fast times on lap 10 or lap 18.



No tire pressure adjustments for just doing 1 lap. I probably gave up a few tenths doing so. I know there was more in this but I didn't need to go much faster than a 2:00.5 so a nice 1 and done for TT to lock that up.

doward

Good weekend. Fun hanging with Charlie and Jen and some of my new racing buddies. Everybody was super welcoming and Charlie's family played fantastic hosts to Megan and I. Thanks again man.

The car was a handful. We have changed a boatload of stuff compared to the dyno reclass build I ran all season.
New Gen2 Xida shocks, new engine, new Megasquirt pnp2 ecu, new SuperMiata OsGiken diff, new catless Racing Beat exhaust, bushings, alignment, mirrors, on and on...

My collarbone injury meant we made a couple compromises in the setup. We ran it with only ~2* of caster to require the least ammount of steering effort possible. Until the day of, we had no idea how much left arm strength I would have. With the thousand pounders and no caster, there was literally zero steering feedback. There was also very minimal self centering of the wheel, I had to manually unwind the wheel on corner exits. You'll see about a hundred little steering inputs/corrections in the video. This was after 4 straight days of driving the same car on the same track, this was about the smoothest I drove the entire event. LOL

As the new engine loosened up throughout the weekend, we kept needing to add more ballast AND de-tune it. On Thursday's test day, it made 148.8whp on a map that made ~147 on Tuesday, So I immediately dropped it down a map(~144ish on the home dyno). I ended up dropping another map on Friday(~141), and by mid morning Sunday It was back up to 146.9 during a compliance check after TT session #4.

We ended up running Saturday and Sunday with ~205lbs bolted in the passenger floorboard plus a full tank of fuel for the championship race. Goal was to finish over 2460 so even if it made 149whp, I'd be safe.

We scrubbed a set of sticker R7s on Thursday and I only ran them for two TT laps Sunday morning, plus the championship race.

Here's lap #2 on sticker R7s:

1999NB

Wasn't this a fresh race build from your employer? ~147whp from ~4000RPM up, yes (so like 175-180whp without de-tuning the top end)? The motor loosened up and kept making more power, then started to fail, correct? What did you make in the post-race dyno?

I saw smoke, and was curious why there wasn't a black flag. Earlier I saw your top wiggling around and carrying on - I heard the rear bracket broke, and assumed you'd get a meatball for that, yet Justin got a black for brake lights. Lady flagger luck was on your side a tad.

doward

I don't recognize your screenname, who are you?

Not exactly. Valve springs and oil pump on an OE rebuild, breathing through the stock cast iron exhaust manifold. My max-power map made a peaky 147.26 @ ~6500 on Tuesday. This engine is far from an ideal "Kansas" power curve motor.

Here's Sunday morning's compliance check, down 2 maps, also spiky due to the broken coilpack mount: This map made 141 on our home dyno. Call it 145 on MCE. Did that extra 4whp come from loosening up, or just MCE being MCE. It sounded like everyone saw bigger % swings than we did.





Something happened, yes. We don't know what yet. It fired right up and drove off the trailer with no strange noises when I got back Monday morning, but was down on oil at the post race dyno where it made 133/135/136. Making more power on every run like every other MCE check I did. Not obvious that it's emptying the cylinders of oil, but that's my best theory right now.
Best guess is that the stock PCV system failed and started dumping oil into the intake. Whether because it cant handle the lateral loads of 1000lb springs on primed R7s, or if my leftover junkyard accessory parts almost cost me the championship, who knows.


Smoke started in Sunset pretty late in the race. By the time it was happening in more than 1 corner, there were only 2 laps left. Thankfully, race control had a bit of time and place/context awareness before they would have had to meatball me during the white flag.

I wouldn't call it luck.
I won because we prepared for nearly every situation. We had plan b's for every plan b, and ended up using most of them (extra ballast, softer maps, extra wheels/tires)
I created a large lead early on by doing a better job in qualifying and running the fastest race laps. I ended up needing that lead while I pedal'd it in to the finish with a mechanical issue.

flier129

iTrader: (7)

Went down to Barber this weekend, which is an amazing facility and track. 10/10 would recommend. My friend and I decided to do a team-entry since his TTB M3 was down and I was unsure on how my performance would be since this would be the first time back out on track after slamming my Z into the wall at Road Atlanta. So it all worked out.

In the middle of last week I noticed only 4 in TTE and 5 in TTD, so I decided to bump on up for a chance at contingency. Didn't really change anything on my car for TTD, I just didn't have to worry about weight. In my 2410lb car that usually means make sure I have 1/4 tank or ~2.5gals for impound.

Here's one way of doing it...... TONS of mistakes I know. I was also being really conservative in several spots. This was my morning session on Sunday with a 1:47.2xx. My afternoon session I built up more confidence and ran a 47.8xx in the heat of the day. I assume a soft TTE record of 1:46.7 since I wasn't far off and I didn't drive that well.



Then here's the correct way....James running a blistering fast 1:43.9xx Sunday morning. The TTD record is a 1:43.5xx. The car weighed around 2380lbs +/- 5lbs when he ran this session, 12th heat-cycle on this set of R7s



It was painfully apparent that I need stiffer springs, currently on 700/400 still. It would of been pretty beneficial not being on the bump-stops through several high load turns at this track.But it was great to see car run well under SM times, Steyn has times in the 45s.

Currently trying to decide what class to run next year between TTE and TTD. I think either would be fun, but I just want people to run against.

cucamelsmd15

So, Ive been staring at the multitude of B6P and BP8 motors and parts in the barn deciding what to do with them.

Im half tempted to take a shot at a 0 points B6 build. I think it would make power, but lack in torque. At current base classing, it would be 200+ pounds lighter than the closest 1.8 based points car. That would be an interesting exercise...

If I go the route of a BP8, Id be stuck on a dyno reclass for next year and then see what shakes out for ST* rules later.

Whats the general rule of thumb for building a race motor with clearances etc? Having just experienced an oil pump failure in a rental seat on Friday practice at the VIR 13 hour and subsequent spun bearing that resulted in a motor swap, Id like to make sure I get this right.

So, bearings, OEM head gasket, rings, deck the block, shave the head, what else?

jix87

If you're talking about a "0 points" build - the rules allow a 0.020" overbore, valve springs and retainers, and balancing/blueprinting. Forged pistons and rods are legal, but must weigh equal to or greater than the OEM parts. Compression can be increased up to 0.5 over stock (head shave). Nothing else in the head can be touched - no port/polish, no lighter or back-cut valves, no tapered valve stems, etc.

I keep seeing people throw around things like "175-180whp no points race motors" detuned to the power limit. I just don't see any way you could get near those numbers without serious head work. You could do it under a dyno reclass, but not within the rules of a points build.

If we get dropped down to 17:1 next year like it's proposed, and the dyno reclasses are left alone - the dyno reclass with a $$$ detuned built motor and aero (under a no * reclass) becomes more attractive, but a lot more expensive.

Savington

iTrader: (31)

Repeat after me:

low weight is not an advantage in PT

low weight is not an advantage in PT

low weight is not an advantage in PT

low weight is not an advantage in PT

BMWidmer

......


Sorry to hear you smashed your Z

doward

Correct.
A reclass motor is the expensive one. In a reclass build, the goal is to make your power cap essentially forever.

A points build can't make those numbers.

flier129

iTrader: (7)

me too **** happens

jix87

I'm coming! Just don't bring James to too many races, Jeebus.

cucamelsmd15

Hot off the presses...

PTC 14.50:1 (using ST4 formula and Avg HP)
PTD 14.25:1
PTE 16.50:1
PTF 19.50:1

Tires:
6) The following DOT-approved R-compound tires: Toyo Proxes RR, Hankook TD
Pirelli Trofeo R +5
7) The following DOT-approved tires and those R-compound tires with a UTQG treadwear
rating over 40: BFG Rival S, Bridgestone RE071-R, Maxxis RC-1 (examples: Kumho V700,
Kumho V720, Michelin Pilot Sport Cup & MPS Cup 2, Nitto NT01, Pirelli PZero Corsa,
Toyo R888, Toyo RA-1, Yokahama A048, etc.) +4

Hmmm, what should I use 3 newfound points for.... Diff or Airdam...

emilio700

iTrader: (3)

Rival-S and RC-1 for the same points? Bummer they nerfed the RC-1. Does simplify things though. Everything 100tw and above is the same tier.