Dyno mystery. Need your help

[dvallis]

DigitalWave is right. And I'd go further saying tunes are like snowflakes ... every darn one is different once you start modding things. Would not want someone loading my tune and blowing up an engine....

[dvallis]

Sleeved a block boss from M10 to M8 for a knock sensor next time we dyno



Also adding an aux O2 bung, so the dyno can read AFR

...

[dvallis]

Update here. Was the Nuke Gear. We amputated and replaced with a solid gear 0/0 TDC.

Valves were not bent. (Wooooo!) Compression showed 210/211 psi on all 6. Ready for a re-tune, but I'm...

[dvallis]

IVT: Involuntary Variable Timing

Amputated the Nuke gear. Confirmed we had slipped to 10 degrees retard. And was probably moving around under hard deceleration. Involuntary Variable Timing....

[dvallis]

Thanks Nando. 5 CAM degrees or 5 CRANK degrees?

[dvallis]

Been starting at this pic for a while, wrapping my brain around what happened. When the bolts came lose, belt and outer shell of cam moved clockwise. Valves opened later with respect to TDC. We got maximum...

[dvallis]

Owwwwww! That hurt! : - )

[dvallis]

Thanks for the tip nando. We might keep the cam gear and dial in a bit of mechanical advance. How much does the M20 stock cam seem to like? We are running 284/272

[dvallis]

So who is actually running mechanical advance to make more power? How many degrees and with what cam? I'm running a 284/272.

Let's hear a roll call.

[dvallis]

So who is actually running any mechanical advance to make more power. With what cam? I'm running a 284/272.

Let's hear a roll call.

[dvallis]

I -thought- they were properly torqued but obviously screwed it up. :-/ Nuke Gear is going in the trash. Back to stock.

Compression test after re-establishing timing will tell us if the valves...

[dvallis]

Cam gear threw a bolt and slipped. We were running 20 degrees retard. Nuke gear is getting deleted. We'll do a compression check to see if the valves were damaged. Deeper valve pockets may have saved...

[dvallis]

It was #1. Frigging adjustable timing gear threw a bolt and clocked to the stops

...

[dvallis]

1. Nuke timing gear slipped?
2. Injector stuck open
3. Compression
4. Leak
5. Fuel pressure
6. Spark plugs
7. Plug wires

We'll be looking into all this....

[dvallis]

Car was running 100% when we pulled into the dyno garage. Ran great, idled great. Once it was bolted to the dyno, in neutral, BEFORE any pulls, -something- happened.

What The F?
...

[dvallis]

Bolted to the hub dyno.

...

[dvallis]

Dumped the 0W break in oil today. Had some metal particulate as expected but nothing out of the ordinary



10 new quarts of Moly 10W60



Oil pressure...

[dvallis]

Found our new tuner. We're taking it to Bardabe Performance here in Austin. He's got a Dynapack hub dyno and has a lot if experience using it.

We're changing out the break-in oil and filter...

[dvallis]

We put the rest of our 100 break-in miles on The Beast yesterday. This thing is really strong off boost. Co-pilot kept me at partial throttle and out of boost, LoL.

We data logged the whole...