Steve, you wouldn't happen to be going to Sebring this weekend are you? We're doing a group drive out there on Saturday so I'll keep an eye out for you if you're going to be there.

I'm coming back!

 

Aw **** son! We need more regular track buddoes for the group. Get on it.

 

Wait! What turbo is that?

I was at Sebring two weekends ago. Daytona November 1&2.

I've almost finished destroying the Chinese turbo I had damaged and rebuilt. So I'm going to use the damaged GTX2867 I bought from you for the track day. It's still got a damaged turbine wheel.

 

It's a GTX2860. After I spent +$1000 buying that damaged used turbo I was a little reluctant to buy used again and since I already had the turbine housing there wasn't much difference in the GTX vs GT series.

That 2867 always worked fine for me aside from spooling slow. I datalogged a bunch of +300whp pulls. This will give you an idea how it spooled for me, it'd hit 13psi by 4000rpms on the wastegate:

 

Scott,

I studied that exact graph when I was deciding what to do next. I figured that if it held together without exploding then it would be good enough for now. The bastardos at Garrett won't do an exchange CHRA if there is any damage to the turbine wheel at all on a ball bearing unit. I would have to buy a completely new CHRA at full price. So that makes the whole thing an expensive paperweight if I don't use it. I guess the compressor wheel and housing would still be worth something as spare/upgrade parts for someone, but meh. I'll see how far it takes me. If I hadn't had it in the garage I'd be scrambling to buy something right now.

 

3 inch V-band adapter has been welded to the exhaust housing of the GTX2867R by a pro welder. Time to install on manifold and see if exhaust still fits. It looks to be over very slightly from the Chinese 2870.










Say "Aaaahhhhh!"

/doctor



The bolts and screw were just to hold it until it was welded.

 

Well, I'm here at Daytona. After the first session of the weekend I can report that I need a taller rear end gear if I ever plan to run this track seriously. Using the factory 4.10 gear and only on wastegate 8psi with the EBC turned off, the car is on the revlimiter long before it runs out of front straightaway. 143+ mph indicated (didn't have the GPS running).

 

Confirmed rev limited at 143.7 on the GPS.

 

Is that on a 6 speed or 5 speed?

How's the car feel at those speeds? I've always felt like anything past 120 was awfully uncomfortable in a miata.

 

Five speed, but the top gear ratio in the six is almost exactly the same.

Megasquirt has begun doing resets while on track and I don't know why. I don't get a signal for my laptop here so I can't easily look up causes. Advice would be great if anyone has dealt with this previously.

 

I was also hitting the top of 6th. With my 4.1 rear end that should put me at 140mph at 7200 rpm. It was actually incredibly stable on the track. Even when you transitioned off of the high banks onto the flat straights

 

Steve, have you talked to puddymod? He's big in the s2000 community with rearends, he's local, and I know he's done several miatas. I remember seeing a 6 speed in the back of your truck... pairing that transmission with a 3.30 or 3.63 would work out real nice.

 

I think poor Ryan has blown his engine. He says he possibly missed a shift and zinged it.

And my megasquirt continues to reset more and more frequently. It is barely driveable.
:(

Other than that, it was a pretty good weekend.

 

Ryan dropped his car off at my shop last night. Engine swap party anyone?

What do you think is going on with your ECU?

 

Not sure on the ECU. Voltage looks good and so do most of the sensor readings.

Of course I'll help with the engine swap. I'm guessing Ryan is just happy he didn't have to drive my car back from the track with it sputtering and jerking. I was prepared to let him do it but he got a better offer

 

The last thing we need are 2 blown engines.

 

Is the MS resetting or is power dropping out for a short amoutn of time with the ecu still powered? The first one is almost certainly a loose connection to or inside the ecu, the second is something I struggled with before, it felt like fuel starve, it looked like fuel starve, it was a bad cam sensor/cam sensor wiring.

 

The tach dropping to zero momentarily causes me to think it is either a connection or cam sensor.

 

If the tach drops out then it would be either the ecu shutting off or the crank sensor. When My cam sensor **** the bed it was just like the car would stall, the tach didnt drop out but it had no power and the wideband went full lean.

 

Video from Daytona on Sunday morning (before the resets got too frequent).