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Share timing tables?

Yes eabras, guys please add compression ratio data and other relevant parameters when you post a map. Otherwise what are we comparing?

well I mean you have to trust that timing is verified and stays consistent through the rpm range for a given car as well. Any number of things can affect that and "not be seen"... improper edge triggering, wrong dwell, unverified TDC angle. Frame of reference and shape are about all you can really derive from someone else's timing map unless it's an identical setup (and even then, some of the above still apply).

I mean, I could post the pump gas timing map for the last 16vT I tuned (or, tried to :-/ ), and yall wouldn't understand it at all-hell I don't even understand it.
 
I mean, I could post the pump gas timing map for the last 16vT I tuned (or, tried to :-/ ), and yall wouldn't understand it at all-hell I don't even understand it.

I'd be interested in that. The high compression NA 16v timing table was basically 10deg advance from idle to 8k rpm. It didn't like much advance at all. I think the total timing change on the driveable area of the map was 35deg.
 
it was wrong, the engine wasn't a high compression engine and it wasn't running a lot of boost. -8 degrees at like 12psi or something
 
like I said, it doesn't make any sense. it just happens to be an extreme example. Had one years ago in the opposite direction.. car wanted like 45 degrees of timing at 5500 at 14psi, go figure that one out lol
 
I am concerned about exhaust temps especially under prolonged boost.

I ran a NA Neon at the local dirt track and it burned my feet from the exhaust lighting up like a lava lamp at 20? btdc, at 36? it was perfectly happy.

This Volvo I am working on has already burned up a manifold and turbine housing. Crack city for both, looking for some longevity from this setup.

Pretty sure the way to do that is to decrease boost and increase spark timing, so it will make power instead of exhaust heat.

So first I need boost control working well before I can advance the spark.
I didn't build the motor and don't know what is in it.
So I am tuning by braille.
 
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Install a EGT and monitor the temps. You don't want the pre-turbine temps to exceed 850 degree C or your turbine wheel will pretty much drop off from the heat cycles. If the ECU has the functionality use the EGT values to enrich the fuelling to 0.70 lambda when if gets close to 850C.
Just keep in mind that the retarding the timing 7 degrees from MBT will only reduce the torque 5% but the bearing loads will reduce 15-20%.
Without a load bearing dyno to sweep the timing to find MBT, don't increase the timing anymore than what you're running.
 
I'd be interested in that. The high compression NA 16v timing table was basically 10deg advance from idle to 8k rpm. It didn't like much advance at all. I think the total timing change on the driveable area of the map was 35deg.

Speaks to how good that cylinder head is.
 
Bumping this back up as I have some ignition tuning questions.

The engine is a b230ft with stock pistons, head shaved .030" with very minimal porting, IPD Turbo cam, and a GTX2860R turbo on a 90+ manifold, NPR intercooler, and some 525cc Siemens injectors (thanks Harald!). I'm using uS for spark and fuel, running just off the stock 60-2 flywheel pattern.

The engine is in a rally car, and will be under 70-100% throttle almost the entire time it's racing.

While doing some initial tuning, I was getting a bit of audible knock around 3500-4500 rpm at 1-1.5bar gauge, so I retarded timing 1deg and it went away. To add a safety buffer, I retarded the area 1 more degree (so now we're at -2deg of timing from initial knock).

My question is: Was 2deg of ignition retard enough from a safety margin? How much are you all reducing timing once knock is heard?

The plan is to get the car on a dyno, but the car needs to be racing in 10 days, so not a lot of spare time at the moment.

Timing table before adjusting, hat tip to Harlard for the table and turbo!:
47797391591_c22f53de9d_z.jpg
 
Id go a bit further, like -3>5* or more from knock, usually I would say peak performance is in that area, ymmv. At least with my typical street tuning method this has worked well.

When tuning on a dyno, starting from a conservative map, you'd normally increase by 2-3* until power drops off with no other changes (fuel, vvt, etc) then pull it back to just shy or more depending on headroom level for temps, fuel quality, or baro changes.
 
Just got the chance to see the insides...

Screen-Shot-2019-05-21-at-8-47-17-PM.png


Limited to ~240KPA no sign at all of any detonation.

rickpiston.jpg


I'd put those pistons back in but the wrist pins are loose (2x)

Head gasket was on the brink of failing, exhaust valves are that pink "I'm retarded" color.

rickhead.jpg
 
I did not think they still sold this stuff, back in the 80's Ford sold it as combustion chamber cleaner.

cleaner.jpg


This is what cleaned that piston, it had a carbon knock thick layer of doodoo.
Melted off after a cold overnight soaking in the CRC.

I did a test using SeaFoam, MarvelMystery Oil, and CRC to remove the carbon.

Conclusion Marvel Mystery Oil has a happy smell but poor carbon softening.

SeaFoam is mostly alcohol (I wanted to drink it) and was barely better than the MMO.

CRC Ding Ding Ding!! Winner! Winner! TuneUp in a can! I'll be keeping it in stock. CRC Part # 05319
 
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