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Old 01-30-2012, 09:32 AM   #61
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That's a tuning fail right there. No engine can sustain detonation for any lengthy period of time.

light det for brief periods you may get over a long period of time, but heavy or sustained det will kill the engine pronto.

Next time invest in some detcans and tune properly rather than assuming it'll all be fine...
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Old 01-30-2012, 10:07 AM   #62
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Quote:
Originally Posted by richyvrlimited View Post
That's a tuning fail right there. No engine can sustain detonation for any lengthy period of time.

light det for brief periods you may get over a long period of time, but heavy or sustained det will kill the engine pronto.

Next time invest in some detcans and tune properly rather than assuming it'll all be fine...
Ok I agree.

So how could I stop deto? I can't see the difference with a jackson racing kit and my setup...
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Old 01-30-2012, 10:31 AM   #63
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Tuning, reduce timing & add fuel as appropriate, whether that's appropriate or not is whether you can hear det or not
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Old 01-30-2012, 10:46 AM   #64
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Originally Posted by richyvrlimited View Post
Tuning, reduce timing & add fuel as appropriate, whether that's appropriate or not is whether you can hear det or not
Ok I will do it with focus next time
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Old 02-06-2012, 05:26 AM   #65
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After a little bit of cleaning...





Deto should make melted zone right? There is none.
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Old 02-06-2012, 11:25 AM   #66
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No, it starts with small dimples with rough centers the size of the head of a pin and get larger and can lead to entire rough areas on the surface of the piston. That is unless the rings break quickly and the detonation isn't continued for a prolonged time.
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Old 02-06-2012, 11:50 AM   #67
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If you haven't thrown them away, check the insulators on the spark plugs. Detonation will leave telltale little ***** of aluminum stuck to the porcelain. The larger the *****, the heavier the detonation, and more ***** means higher quantity.

And I think your ring groove issues are cylinder wall wash down (overly rich condition washing all the oil off the cylinder walls and causing premature wear) causing excessive friction between the top ring and the ring groove. Usually you get really severe skirt damage as well with wash down, but detonation simply wouldn't cause that kind of ring groove damage without absolutely trashing the piston crowns and breaking the top ring land off in places...
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Old 02-06-2012, 11:52 AM   #68
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Originally Posted by sixshooter View Post
No, it starts with small dimples with rough centers the size of the head of a pin and get larger and can lead to entire rough areas on the surface of the piston. That is unless the rings break quickly and the detonation isn't continued for a prolonged time.
Ok thanks for your preciseness.

(new word learned: dimples lol )
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Old 02-06-2012, 12:05 PM   #69
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I will check insulators. thx

Yeah!! second new world learned : telltale
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Old 02-29-2012, 10:27 AM   #70
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Parts arrived:

-full gasket kit
-ACL bearings
-ACT clutch XTMM
-timing kit
-NGK spark wires
-NGK BKR7E-11
-OEM pistons + rings



I'm still waiting for connecting rods... Why are USA so far :(

Some painting:



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Old 02-29-2012, 11:58 AM   #71
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did you paint the aluminum oil pan aluminum colored?
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Old 02-29-2012, 12:26 PM   #72
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Yes, old paint has suffered from salted roads.

I put a light paint fog or film (don't know the best word for paint vocabulary) to keep good dissipatign properties.
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Old 03-02-2012, 06:42 PM   #73
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It wasn't painted. Should have just bead blasted it.
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Old 03-03-2012, 05:45 AM   #74
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hum, mine was painted before... Maybe from the previous owner.

I will clean that up. Thanks Falcon.
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Old 03-03-2012, 10:08 PM   #75
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Likely from a PO. Three pans I've had were all 'polished' alum. 'Polished' meaning a shitty job but it was still raw alum.
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Old 06-07-2012, 02:41 PM   #76
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Hello everyone,

I need some analysis on my AFR table.

New engine is running well with the G supercharger (muuuuch better than this autoumn, now I think pistons rings were broken before I put the supercharger on it)

I wanted to make a preservative table, am I on the right way or not?

Yellow dots are the active cases in an WOT accel from 1000rpm to 5000rpm

92kpa = 0 boost
127kpa = 5 psi
162kpa = 10 psi

Thanks for your help

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Old 06-07-2012, 03:46 PM   #77
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Originally Posted by hustler View Post
Coming from the land of VW I can say that you picked the least reliable supercharger on Earth. However, it's nice to see the fab work on this.
Yeah haha. I haven't seen a G60 that didn't need a rebuild unless it was just done.
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Old 06-07-2012, 05:34 PM   #78
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Credit to Hustler for that one

The targets look sane if that's what you are asking, but I'm not necessarily the most experienced person in the room with this kind of stuff. Is this thing intercooled yet? I seem to remember you had some insanely high IATs, that'll certainly lead to detonation.

Edit: Yeah, its intercooled. My reading fail. What does your spark table look like?

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Old 06-07-2012, 06:01 PM   #79
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? I don't get why you post this, but I'm starting from 92kpa (engine off) not 100kpa, so 92+35=127 for 5psi of boost

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Originally Posted by EO2K View Post
The targets look sane if that's what you are asking, but I'm not necessarily the most experienced person in the room with this kind of stuff. Is this thing intercooled yet? I seem to remember you had some insanely high IATs, that'll certainly lead to detonation.

Edit: Yeah, its intercooled. My reading fail. What does your spark table look like?
That's what I am asking, you're right. In fact, I wonder if I must add a AFR target like 12.2 somewhere between 12.5 and 11.8? (maybe it will not make a driving or a power difference)
For info, yesterday my IAT was 80F

Spark table is really conservative under boost, I will post it tomorrow.

Thank you
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Old 06-07-2012, 07:08 PM   #80
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Quote:
Originally Posted by phenixmt View Post
? I don't get why you post this, but I'm starting from 92kpa (engine off) not 100kpa, so 92+35=127 for 5psi of boost
That does not sound right... you should be sitting @ 100kpa with the engine off unless there is something here that I don't understand. How many thousands of feet/meters above see level are you?

I posted my AFR and timing table in the thread of complaints that I try to pass off as a build thread. I've fiddled with the timing a bit, and my MS2 based DIYPNP has more resolution than your MS1 based MSPNP, but my timing seems to be close enough to safe with my 9.5:1 1.8 engine that nothing has exploded yet. You could rescale it and use it for reference. Don't just blindly use my (or any) map, that would be A Bad Thing™

Make triple sure your base timing is set/configured correctly. I had mine 3 off when I first started screwing with things. Just for fun, I changed it to be 10 off and the car still started and ran, but the additional 10 would probably have melted something if I had driven it under load.

Last edited by EO2K; 06-07-2012 at 07:26 PM.
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