Latest Experiment…Failure!
09-08-08, 07:55 PM
#151
To confirm the thoughs that the housing is growing due to heat. My external coolant hard line setup is showing signs of leakage, but doesn't leak under normal street driving conditions. I also haven't seen any noticeable loss of coolant. The highest recorded water temp was 230F and 245F oil during the time attack I did a while back. Need to upgrade my oil coolers.
Currently I see knock at 15 degree IGL and it's very light as well ~60 Hz. This is at 15/16 psi, from N16 through N19, ~200F (93C)water temperature, 97F (36C) air temperature and ~11 afr. This would be just before ignition timing is retarded 3 degrees due to water temp.
The rest of the time I see below 15 Hz as far as engine noise.
I feel the coolant mods I did has made a difference in openning up my timing window. Then again I may be wrong, I'm not totally done tuning though.
Currently I see knock at 15 degree IGL and it's very light as well ~60 Hz. This is at 15/16 psi, from N16 through N19, ~200F (93C)water temperature, 97F (36C) air temperature and ~11 afr. This would be just before ignition timing is retarded 3 degrees due to water temp.
The rest of the time I see below 15 Hz as far as engine noise.
I feel the coolant mods I did has made a difference in openning up my timing window. Then again I may be wrong, I'm not totally done tuning though.
09-08-08, 10:28 PM
#153
Eye In The Sky
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Spark plug temperature range thought!
Considering that the intake charge is the main cooling agent for the spark plug electrodes, and that E85 cools way more than gasoline and has a higher octane rating; a warmer plug should be used for E85 than you would for gasoline.
That is why 10-11 leading plugs may not work well with E85.
Considering that the intake charge is the main cooling agent for the spark plug electrodes, and that E85 cools way more than gasoline and has a higher octane rating; a warmer plug should be used for E85 than you would for gasoline.
That is why 10-11 leading plugs may not work well with E85.
09-10-08, 07:33 AM
#155
"Elusive, not deceptive!”
Thread Starter
To confirm the thoughs that the housing is growing due to heat. My external coolant hard line setup is showing signs of leakage, but doesn't leak under normal street driving conditions. I also haven't seen any noticeable loss of coolant. The highest recorded water temp was 230F and 245F oil during the time attack I did a while back. Need to upgrade my oil coolers.
Adam, I don't remember if you have tight fitting ducts on your new oil coolers. That might be the answer to the high oil temps.
Currently I see knock at 15 degree IGL and it's very light as well ~60 Hz. This is at 15/16 psi, from N16 through N19, ~200F (93C)water temperature, 97F (36C) air temperature and ~11 afr. This would be just before ignition timing is retarded 3 degrees due to water temp.
If you check your IGN L logged it will be 2* more advanced than your Map IGN L. I think you are too advanced and may be giving up HP and longivity. I think Chuck runs his advance way more conservative than yours.
The rest of the time I see below 15 Hz as far as engine noise.
I feel the coolant mods I did has made a difference in openning up my timing window. Then again I may be wrong, I'm not totally done tuning though.
Adam, I don't remember if you have tight fitting ducts on your new oil coolers. That might be the answer to the high oil temps.
Currently I see knock at 15 degree IGL and it's very light as well ~60 Hz. This is at 15/16 psi, from N16 through N19, ~200F (93C)water temperature, 97F (36C) air temperature and ~11 afr. This would be just before ignition timing is retarded 3 degrees due to water temp.
If you check your IGN L logged it will be 2* more advanced than your Map IGN L. I think you are too advanced and may be giving up HP and longivity. I think Chuck runs his advance way more conservative than yours.
The rest of the time I see below 15 Hz as far as engine noise.
I feel the coolant mods I did has made a difference in openning up my timing window. Then again I may be wrong, I'm not totally done tuning though.
A dyno run could also nail down a peak torque vs. IGN timing few cells to anchor the rest of your IGN map.
Barry
09-10-08, 10:33 AM
#156
The oil cooler ducts are completely sealed with aluminum heater ducting tape.
Actually the HP was going up consistently up until I stopped to this timing configuration. I definitely have gains to be had from N8 to N13 though. You maybe right as far as being too advanced for longevity purposes.
Actually the HP was going up consistently up until I stopped to this timing configuration. I definitely have gains to be had from N8 to N13 though. You maybe right as far as being too advanced for longevity purposes.
09-29-08, 11:18 AM
#160
Well Jeese sk8rpunk1983 popped the motor on our way back from SSXI. Once the fd gets transported back to Portland I be will tearing it apart. The motor as well as the intake temps wet too cold. It leaned out to 11.94afr at 0.85 Bar with an IGL of 17, 4 deg. more advaned than what I set it at. Knock of 81.
Last edited by afgmoto1978; 09-29-08 at 11:30 AM.
09-29-08, 08:52 PM
#161
Well Jeese sk8rpunk1983 popped the motor on our way back from SSXI. Once the fd gets transported back to Portland I be will tearing it apart. The motor as well as the intake temps wet too cold. It leaned out to 11.94afr at 0.85 Bar with an IGL of 17, 4 deg. more advaned than what I set it at. Knock of 81.
-J
10-03-08, 12:23 PM
#167
I realize the air temps were cool (I'm usually around 55C without AI during extended hard driving) but that blows my mind something (maybe its a side seal?)would let go in that situation.
Sorry for your loss, hopefully we all learn something on this one
10-03-08, 07:13 PM
#168
Well, it has knocked a few time before this one during tuning and track events under extreme environments, but all at 65 knock levels and the motor was really hot i.e. +215F water and +230F oil.
I'm total sold on the Iannetti ceramic seals, won't go back even with the added cost. It would be cool if it was a side seal, but I doubt it.
I'm total sold on the Iannetti ceramic seals, won't go back even with the added cost. It would be cool if it was a side seal, but I doubt it.
Last edited by afgmoto1978; 10-03-08 at 07:15 PM.
10-04-08, 07:23 AM
#169
"Elusive, not deceptive!”
Thread Starter
I am not as conservative as Chuck Westbrook on timing but looking at your log I would have used the 1500 line as my max knock target and would have started pulling timing on any cells above that line.
I have had to change my 4-stroke thinking about advance.... learning that max advance does not equate to max HP. Starting the burn at the proper point leads to best BMEP.
Please post post mortem pictures of the damage.
Barry
10-04-08, 11:27 AM
#170
Old [Sch|F]ool
Max advance doesn't lead to max HP there, either.
The difference is that for most piston engines, you have the option of turning up the compression ratio until you become detonation limited at best advance.
And in a lot of cases, the combustion chambers are crappy enough that advance is detonation limited, not power limited.
Complicating matters is that if you do it right, increasing CR *decreases* the amount of ignition advance is optimum! Best HP might be as silly high as 38-40 degrees on something with only 10:1 compression but if you get it on up there then you see that closer to 30 degrees is best. Or even less than that if you have good chambers...
10-06-08, 11:25 AM
#172
Adam, sorry to hear about your lost rotor!
I am not as conservative as Chuck Westbrook on timing but looking at your log I would have used the 1500 line as my max knock target and would have started pulling timing on any cells above that line.
I have had to change my 4-stroke thinking about advance.... learning that max advance does not equate to max HP. Starting the burn at the proper point leads to best BMEP.
Please post post mortem pictures of the damage.
Barry
I am not as conservative as Chuck Westbrook on timing but looking at your log I would have used the 1500 line as my max knock target and would have started pulling timing on any cells above that line.
I have had to change my 4-stroke thinking about advance.... learning that max advance does not equate to max HP. Starting the burn at the proper point leads to best BMEP.
Please post post mortem pictures of the damage.
Barry
As far as my timing goes I had backed off considerably from the timing map I posted earlier and I was seeing max knock of 15 throughout the rpm range, except for when I was pushing the car hard for long period, i.e. the Palomar Mtn run. I saw ~60 at 6200-6400 rpms a couple times once the motor got good and hot.
A BMEP recording device would be ideal as far as understanding what really is happening. From that a true rotary tuning ethos would be established. Granted each motor is slightly different, but the general tuning window would always apply.
10-07-08, 07:31 AM
#173
"Elusive, not deceptive!”
Thread Starter
Adam, were you using any water/ alcohol injection at that time?
Do you have any other safeguards that might drop ign timing with added air/water temps?
What range plugs were you running in the leading/ trailing positions?
Barry
Do you have any other safeguards that might drop ign timing with added air/water temps?
What range plugs were you running in the leading/ trailing positions?
Barry
10-22-08, 09:02 AM
#175
Attached a pic of one of the housings I did for my recent (and first entirely solo) rebuild.
I just did the common jacket mod, nothing super special. Used a dremel engraver bit (#100) on the drill press and went one groove at a time. The only other thing I did thats neat is welded up the EGR holes in the exhaust sleeves and groudn them smooth. Take a good look at a housing next time you get the chance and take note of all the cavities that would be filled with (at WOT +1600F) HOT exhaust gas and soaking into the coolant as a result.
Don't know how effective that mod will be, but I'm giving it a shot nonetheless.
On the rebuild I'll do on the keg I'm swapping this one for, I plan to do similar jacket grooves (done with a dremel engraver bit on the drill press, nothing too special...) but with my newly found thin and LONG end mill I will add a piece of 1/8" AL to either side of the leading plug bore on a diagonal. I'll be cutting out a piece from center of the "divider/support" between the dowel bores and then notching the inside and outside edges (inside on the upper tension bolt hole, outside on the lower) to provide support for the piece. Also, doing it on a diagonal will allow for support/guide notches at the ends of the additional piece without having to cut into the tension bolt land. It will be a minor interferance fit and the sandwiching of the engine will also prevent it from uprooting afterwards.
Keep the discussion/thoughts going
I just did the common jacket mod, nothing super special. Used a dremel engraver bit (#100) on the drill press and went one groove at a time
. The only other thing I did thats neat is welded up the EGR holes in the exhaust sleeves and groudn them smooth. Take a good look at a housing next time you get the chance and take note of all the cavities that would be filled with (at WOT +1600F) HOT exhaust gas and soaking into the coolant as a result.Don't know how effective that mod will be, but I'm giving it a shot nonetheless.
On the rebuild I'll do on the keg I'm swapping this one for, I plan to do similar jacket grooves (done with a dremel engraver bit on the drill press, nothing too special...) but with my newly found thin and LONG end mill I will add a piece of 1/8" AL to either side of the leading plug bore on a diagonal. I'll be cutting out a piece from center of the "divider/support" between the dowel bores and then notching the inside and outside edges (inside on the upper tension bolt hole, outside on the lower) to provide support for the piece. Also, doing it on a diagonal will allow for support/guide notches at the ends of the additional piece without having to cut into the tension bolt land. It will be a minor interferance fit and the sandwiching of the engine will also prevent it from uprooting afterwards.
Keep the discussion/thoughts going