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Evo 8 grenades on the dyno


Turbo.Tim
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2003 Mitsubishi Evo 8.  2.2 stroker motor with only 1000 km on the motor.  ID 1000, 255 pump, fp red.

Took it to the dyno and the motor let go and there is no compression in 3/4.  One of the pictures are the top of the piston in 4.

I am logging AFR but it is off by .2.  So 11.6 was 11.4 on my guage.

Is there any way to determine what might have happened?

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Evo_Log.llg Evo8.pclr

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Melted plug electrode is generally pre-ignition.  With detonation you will generally break things before you melt things, but in some cases if you have relatively strong internals (forged pistons etc) they will handle the mechanical impact of the detonation for long enough that it can generate enough heat in the combustion chamber to cause pre-ignition so the damage is done by the pre-ignition but the root cause is detonation.    

Pre-ignition is something causing the mixture to ignite before spark has occurred and can generate extreme heat since the combustion energy is not all going in to expansion.  Pre-ignition is most often caused with lean mixtures under high load, or when there is something "glowing" in the combustion chamber such as a wrong heat range spark plug, lack of coolant around the spark plug/chamber or something like a fire ring on the head gasket that is too small and hanging into the chamber.  On older engines it can be carbon deposits etc but since yours is fresh you can rule that one out.  Or as mentioned earlier heavy detonation can cause it also.

Was it running ethanol or petrol?  Were the injectors new?  What sort of power was it making before this happened?  The ignition timing in your map is pretty extreme for an evo - generally you are well down in the single digits by 20psi on petrol - was that a prove ignition table or something new?

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This was a fully built motor with forged internals running on pump gas.  The car made 489 on a dynojet.  On the run prior to this one of the couplers blew off.  Not sure if could cause it to lean out.

I was using NGK BRP8ES plugs gapped at .026 on stock coils.  Could I have had spark blow out from not tight enough gap?

 

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Hey guys just to chyme in on this. Built many evos and first off we would always recommend oem plugs and heat ranges. Oem 8 ngk plug number is BPR7EIX and 9 number is ILFR7H. Most common best gap that we used was .022 for both and usually the 9 plugs are already set there. Stock heat range 7 is good to 600wheel with good 93 gas and a good tune. Anything past 600wheel you should be running e85 or another race fuel type which the stock heat range 7 works great for also. My personal 9 has done 790wheel mustang and never had any issues with oem plugs.. With all that said i cant tell how many evos we have had in through our shop that were fixed by removing the colder plugs that were in them and switching them back to oem plugs. I know this isnt the case for everyone but this is what we have found worked the best.

As for your exact situation, sometimes theres no way of telling. It could have been a fully built engine with really great parts but then it ultimately relies on how well the parts were put together. Sometimes it only takes one loose built to be the factor. Not saying that was the issue but there is almost no way of telling for sure with a major failure.

Iv seen plugs look like that after removing from a failed engine that had a failed head gasket, coolant was getting into the cylinder of the damaged plugs, not to say the plug didnt melt first and then the gasket went. Usually if spark is blowing out you feel it on the dyno and if it doesnt ignite, the cylinder stays wet with fuel and wont melt a plug that easily. could be any number of issues. Might have to tear the whole engine apart to find out what may have caused it. If you do figure it out post up so we can see what the cause was. best of luck!

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27 minutes ago, k4nnon said:

Hey guys just to chyme in on this. Built many evos and first off we would always recommend oem plugs and heat ranges. Oem 8 ngk plug number is BPR7EIX and 9 number is ILFR7H. Most common best gap that we used was .022 for both and usually the 9 plugs are already set there. Stock heat range 7 is good to 600wheel with good 93 gas and a good tune. Anything past 600wheel you should be running e85 or another race fuel type which the stock heat range 7 works great for also. My personal 9 has done 790wheel mustang and never had any issues with oem plugs.. With all that said i cant tell how many evos we have had in through our shop that were fixed by removing the colder plugs that were in them and switching them back to oem plugs. I know this isnt the case for everyone but this is what we have found worked the best.

As for your exact situation, sometimes theres no way of telling. It could have been a fully built engine with really great parts but then it ultimately relies on how well the parts were put together. Sometimes it only takes one loose built to be the factor. Not saying that was the issue but there is almost no way of telling for sure with a major failure.

Iv seen plugs look like that after removing from a failed engine that had a failed head gasket, coolant was getting into the cylinder of the damaged plugs, not to say the plug didnt melt first and then the gasket went. Usually if spark is blowing out you feel it on the dyno and if it doesnt ignite, the cylinder stays wet with fuel and wont melt a plug that easily. could be any number of issues. Might have to tear the whole engine apart to find out what may have caused it. If you do figure it out post up so we can see what the cause was. best of luck!

Thanks for the response.  The motor was built by Magnus.  Marco fully assembled and timed the motor personally.  This was a 4g64 block with a 4g64 head gasket and timing belt.

 
Head
Magnus 4G63 Cam Gears
Manley Stainless Intake/Exhaust Valves
Kiggly Racing springs
Kelford 272 Cams
Kiggly HLA Oil Pressure Regulator
 
Magnus 4g63 Pistons
Manley Turbo Tuff 156 mm  Rods  
Magnus 92 mm crank
Magnus Head Studs
ARP Main Studs
HKS head gasket
Balance shaft elimination kit
 

I didnt film the one that let go but this was the run before it.  I am planning to pull the head to get an idea of the damage.  Hopefully the head is ok and the block just needs a bot of clean up.  No windows this time.

https://photos.app.goo.gl/YCLRLNTTt2wSFbMdA

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Do you have any idea what fuel pressure was doing?  Might be very worthwhile to install a fuel pressure sensor, especially at that much boost and that small of a pump.

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AFR did not drop and car did not appear to lean out. I do have an external aeromotive FPR.  I was going to install a FP guage and log it but didnt have time before the dyno.  I was hoping to have it done before the first track day.  We were only around 80% duty cycle.  I could probably use a bigger pump.

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That ignition timing still looks pretty extreme for an evo to me, did the tuner have much 4G64 experience?  

To give you a comparison, at 240kpa, 4500RPM your ign table has 11deg advance, in the same cell in my Evo 7 I have 0.5deg, mine is very sensitive to knock around that area and definitely would be knocking its brain out at 11deg.  Mine is stock compression ratio whatever that is and 98octane RON fuel.  

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22 hours ago, Turbo.Tim said:

Interesting build. Magnus is well known over the years so you can most likely trust that the engine was built properly. Although mistakes happen it was probably not related to build or parts quality. As Adam mentioned, it looks like its tune related, or engine safety functions were not set correctly. I actually built my personal 9 engine with a magnus 92mm crank at one time. Its a nice piece. Im currently using a custom Winberg 92mm now. 

 

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Thanks everyone.  I wanted to ensure it was not something mechanical before I invest money to rebuild it just to run into the same issue.

Adam do you have a starting point for a timing map for a 4g64? .5 timing seems extremely low.  Is yours stock bottom?

I will get the knock configured before starting tuning again.  I mistakenly thought he was going to tune that first.  I told him the knock was disabled and needed tuning.

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6 hours ago, Turbo.Tim said:

Adam do you have a starting point for a timing map for a 4g64? .5 timing seems extremely low.  Is yours stock bottom?

On my 4g63 I am at 4* at peak torque. Running an FP Black at 34psi. 93octane with 30% Toluene added. I don't know if 4g64 require different timing values or not.

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12 hours ago, Turbo.Tim said:

Adam do you have a starting point for a timing map for a 4g64?

Below are ignition tables from a stock JDM evo 8.  They have two maps, - one called high octane and one low octane.  Depending on how much activity the knock sensor has seen over time it will determine the blend between these two tables.  Generally when I have looked at stock evos they knock quite a lot so will rarely be using as much advance as is shown in the "high octane" map.  They will be running somewhere between the high and low octane map.  The fuel tune is also very rich in stock form so you actually make better power by pulling timing out and running it leaner. 

The "% Load" axis corresponds pretty close with kpa MAP in general.  As you can see at say 4500 & 240kpa the high octane map is down at 5 deg and the low octane is at -8.  

2G2SVeZ.png

 

zOrAMqz.png

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On 7/15/2022 at 7:09 PM, Turbo.Tim said:

It looks like the adjustable cam gear skipped on me for both the exhaust and intake.  

 

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That is a huge possibility. Witness marks def look like there has been movement. One of the many reasons we would stray away from adjustable cam gears. OEM timing gears are the way to go to avoid this potential issue. Looks like a few different things could have lead up to failure. Very unfortunate but always fixable. 

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I dont think it looks like it moved. If you look close you will see 2 half round marks.. those would be the 2 times the timing was changed and bolt was tightened. 

If it moved you would not have the mark in the middle, as it would slide from right to left.

But you clearly see that half way it was tightened again thus leaving the mark of the edge of the bolt. 

Once you remove the bolt you will probably see the 3rd half round mark.. 

That would tell you that the bolt was tightened in place and didnt move. 

 

my2c

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I'm leaning more towards detonation being the primary cause of the failure. As @remski2 pointed out, knock control was active but not setup completely. 8* of timing at 4500rpm and 1.9bar of boost is too much for the 4g63 that early on imo. The level of noise picked up by the knock sensor also indicates that. 

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Yeah Im not convinced the cam movement would be the issue either.  In VVT engines you can move the cams around 40 or 60degs in some cases without much consequence.

As for the other comments about knock control, it is actually pretty rare to use knock control when tuning as it will often work against you - pulling timing out when you add timing and adding timing when you remove timing etc (a bit like trying to tune a fuel map with CLL enabled).  So it is normal to tune the ignition map with knock control off, then enable it and tune knock control only after you have a known knock free map.  

 

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53 minutes ago, Adamw said:

Yeah Im not convinced the cam movement would be the issue either.  In VVT engines you can move the cams around 40 or 60degs in some cases without much consequence.

As for the other comments about knock control, it is actually pretty rare to use knock control when tuning as it will often work against you - pulling timing out when you add timing and adding timing when you remove timing etc (a bit like trying to tune a fuel map with CLL enabled).  So it is normal to tune the ignition map with knock control off, then enable it and tune knock control only after you have a known knock free map.  

 

Thanks Adam.  I went back and looked at the pictures from when I installed the car and the cam gears look like they were adjusted as stated above.  So I don't suspect they shifted.  So I am back to probably too much timing at peak torque.  I'm going to send out my injectors to ensure that they are flowing correctly because I find it odd that only spark plug 4 melted

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1 hour ago, Turbo.Tim said:

I'm going to send out my injectors to ensure that they are flowing correctly because I find it odd that only spark plug 4 melted

For sure it will pay to confirm that.  Pre-ignition is kind of self perpetuating - so for example if it is borderline on all cylinders but there is one cylinder that is just running a bit hotter (coolant flow or intake air flow etc) then as soon as it starts per-igniting on that cylinder it generates even more heat that cant be expelled so it just gets hotter and hotter every cycle.  

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10 hours ago, Adamw said:

As for the other comments about knock control, it is actually pretty rare to use knock control when tuning as it will often work against you

Well, the way I do it is to get the baseline noise level of the engine with relatively low ignition values and 0% WGDC . Then populate the knock threshold with values 1.3 times greater than the normal noise level. 

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I am running similar timing as you are but I am on e85. If you are running on stock intake manifold you should turn on individual cylinder fuel correction and add 1-2% to cyl 3 and 2-3% of fuel to the cyl 4. Stock evo intake manifold is designed that way that 3rd and 4th cylinder is running leaner than other 2 cylinders. Also 11.4-11.6 afr on pump gas I would say is not lean but on leaner side plus 3rd and 4th cylinder was probably running leaner than that and your timing did not helped at all.

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