Timing vs. boost

[retoropak]

I checked timing on my m10 turbo again yesterday and it seems that i had a tiny 20 degree mistake.

tooth#1 angle on the ms2x was set to 80 degrees and the actual sensor position was at 100degrees BTDC

 

The 200kpa top row on my ignition map was set between 15 degrees@ 2300rpm, 13 degrees @ 3.5k and 18 degrees @7krpm

Boost comes in at around 4.5k on 3rd and about 300rpm lower on 4th and even lower on 5th (i have 3.91 rear end)

Compression is around 8.5-8.8:1 running 93 octane

Now with my small mistake it was more like 33-34 degrees @ 12psi @ 4-5k rpm.  

 

There is no noticable knock.   

 

How the hell the engine survived that much timing? I know that late spool and that 3.91 is helping but is it enough to keep it from kncoking?

I did maybe 1500 mile like this and its still holding up.  

 

 

How much timing is too much? What are you guys running on your m5x and m20 turbo setups?

Thanks

[B C]

This is a very good spark table for an M20 turbo. I made some changes for idle stability and tip-in response but peak power timing was still around 15 deg @ 12-13psi

 

 

I cant answer for how it held up. Glad it was rich enough to keep things safe though

 

I changed some upper right cells to 50 deg advance for demonstration purposes, didn’t realize i had burned them to the controller and drove like that. I heard the audible spark knock but nothing instant or catastrophic had occurred

[KaiserRolls]

Relevant


Could always pay to have it tuned...

[GunMetalGrey]

Snap and I had many late night conversations over a multitude of beers (not really) about timing and numbers. 
What it really comes down to is that you are just looking at a number, does it seem out of whack? Sure, but if the engine was happy with it what does it matter? I found some other errors in my setup that lead me to believe there was a decent latency in timing once the engine was warm, so that certainly attributed to my issues, but at the end of the day you have to give the engine what it wants, not what you think it should have. 

[jc43089]

24 minutes ago, GunMetalGrey said:

Snap and I had many late night conversations over a multitude of beers (not really) about timing and numbers. 
What it really comes down to is that you are just looking at a number, does it seem out of whack? Sure, but if the engine was happy with it what does it matter? I found some other errors in my setup that lead me to believe there was a decent latency in timing once the engine was warm, so that certainly attributed to my issues, but at the end of the day you have to give the engine what it wants, not what you think it should have. 

Burnouts.

[Daggerty]

This is why dyno tuning is the best for the most power and safety. If you are only gaining 10 hp from the extra 10 deg of timing is it worth the risk?