E85 and photo shoot
07-16-2009 | 06:28 PM
#46
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From: Stockholm, Sweden
MBT is still above what degrees? The lower 20's or even higher than your upper 20's?
What do you think the MBT is on our engines with gasoline only (let's say race gas so that knock is out of the equation)?
Also, all the research that I've done indicates that rich mixtures with E85 burn slower than mixtures that are only 10% rich.
What do you think the MBT is on our engines with gasoline only (let's say race gas so that knock is out of the equation)?
Also, all the research that I've done indicates that rich mixtures with E85 burn slower than mixtures that are only 10% rich.
07-16-2009 | 06:38 PM
#48
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MBT will also need to take into account boost pressure (cylinder pressure).
This is where a 'in-cylinder pressure transducer' or ion-sensing equipment and sick fast datalogging would be absolutely amazing...
-Rogue
This is where a 'in-cylinder pressure transducer' or ion-sensing equipment and sick fast datalogging would be absolutely amazing...
-Rogue
Last edited by Rogue_Ant; 07-16-2009 at 07:06 PM.
07-16-2009 | 06:57 PM
#50
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From: Firestone, Colorado
I have tried tuning the ford injectors on a 2.0 mitsu and they were a bitch. Fortunately he went E85 so it was easier.
Then.... we tried some FIC injectors (fuel injector clinic_ delphi based) and they were much easier to get to idle. I would post a link, but right now they have some issue with the site.
Then.... we tried some FIC injectors (fuel injector clinic_ delphi based) and they were much easier to get to idle. I would post a link, but right now they have some issue with the site.
07-16-2009 | 07:02 PM
#51
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Yep, FIC web site is messed up ATM... However I'm not even sure if they have update to reflect their newest injectors anyway.
These are the injectors that the DSM crowd is using with much better idle/low-load drivability then the old Bosch/Ford units:
Click Me
The injector style is slightly different, but can be used in our cars - need resistors (like normal) and second O-rings IIRC...
-Rogue
These are the injectors that the DSM crowd is using with much better idle/low-load drivability then the old Bosch/Ford units:
Click Me
The injector style is slightly different, but can be used in our cars - need resistors (like normal) and second O-rings IIRC...
-Rogue
07-16-2009 | 11:29 PM
#52
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There's some info posted, here somewhere, regarding the factory ignition advance.
As I recall, timing in the middle RPMs was about 17 to 18 degrees, increasing to about 20 in the upper RPMs; and this would be at the factory stock boost of 0.8 bar.
I have a hard time believing that Porsche would be that far off MBT!
07-17-2009 | 12:04 AM
#54
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Friday I prepared new fuel and ignition maps for E85 and Saturday morning I filled up about 65 liters of E85. Loaded the new maps, made some transitional adjustments and everything went smooth as silk. A couple of hours on the road fine tuning the maps and it's close to perfect. I still have some headroom left on the ignition map, will do the final adjustments after the next full tank.
Initial testing at 0.9-1.0 bar shows 60-100 mph at 4.8 sec. I think it will be very quick with full ign. advance at 1.5 bar
Took the opportunity to shot some new pics as well.
Initial testing at 0.9-1.0 bar shows 60-100 mph at 4.8 sec. I think it will be very quick with full ign. advance at 1.5 bar
Took the opportunity to shot some new pics as well.
Hello Duke , car is looking good as ever , still love the color ........
Based on the info you have listed and assume you are holding FP , 420 whp @ 1.25 bar.....
Are you measuring the e-85 ?
regards,
07-17-2009 | 12:21 AM
#55
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From: Australia
I dropped in the 1600 cc injectors today. Those are a bit painful to tune. Even with the correct injector dead times I had to redo most of the fuel map.
Boosting around 1.35 bar: 100-181 km/h 3rd gear in 5.44 sec. 100-200 km/h in 7.6 sec
Pretty decent for a mildly modified engine at this boost level
Boosting around 1.35 bar: 100-181 km/h 3rd gear in 5.44 sec. 100-200 km/h in 7.6 sec
Pretty decent for a mildly modified engine at this boost level
D'oh I see Sid beat me to it. I have also been told that they got the idle going pretty easily with those FIC inj.
07-17-2009 | 05:52 AM
#56
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There's some info posted, here somewhere, regarding the factory ignition advance.
As I recall, timing in the middle RPMs was about 17 to 18 degrees, increasing to about 20 in the upper RPMs; and this would be at the factory stock boost of 0.8 bar.
I have a hard time believing that Porsche would be that far off MBT!
As I recall, timing in the middle RPMs was about 17 to 18 degrees, increasing to about 20 in the upper RPMs; and this would be at the factory stock boost of 0.8 bar.
I have a hard time believing that Porsche would be that far off MBT!
Come on Tommy, we talked about best torque timing without BOOST and without any risk of knocking.
If you then consider the engine is boosted with almost double the atm. pressure AND the fact that it's a production car with a conservative tune AND to tune in the risk fo getting bad, or low octane, fuel a 10-15 degrees reduction from MBT does not seem odd.
If you want to run low ignition advance, by all means please do.
But I have to ask, do you think I could reduce my accelerations below with stock timing advance?
100-181 km/h 3rd gear in 5.44 sec. 100-200 km/h in 7.6 sec
Remember that this is at 1.35 bar on 2.5l with stock valves, stock headers, N/A cam, stock intake etc in a 944 Turbo S with race seats as the only weight reduction. I have yet to see any other 2.5l without more engine mods come close to these numbers at this low boost level.
07-17-2009 | 09:19 AM
#57
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And I have a hard time believing Porsche would dial in maximum torque timing without considering boost and the risk of low octane fuel
Come on Tommy, we talked about best torque timing without BOOST and without any risk of knocking.
If you then consider the engine is boosted with almost double the atm. pressure AND the fact that it's a production car with a conservative tune AND to tune in the risk fo getting bad, or low octane, fuel a 10-15 degrees reduction from MBT does not seem odd.
.
Come on Tommy, we talked about best torque timing without BOOST and without any risk of knocking.
If you then consider the engine is boosted with almost double the atm. pressure AND the fact that it's a production car with a conservative tune AND to tune in the risk fo getting bad, or low octane, fuel a 10-15 degrees reduction from MBT does not seem odd.
.
I reread this thread, and your discussions revolved around full throttle applications. So when I asked the question about your opinion of MBT, why would you answer back to the effect of 32-38 degrees thinking I meant NO BOOST?????????????
07-17-2009 | 09:44 AM
#58
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Because best torque timing under boost is limited by knock!
You specifically asked what I thought the best torque timing was with "knock out of the equation"
And I would NEVER discuss ignition advance without talking about a specific boost level. What do you think, that the optimal ignition advance is a 2d curve "under boost" without any changes whatsoever to the advance on different boost levels?
As I said, run the stock ignition advance if you think that it's the best torque numbers. It's your car, and your power loss.
You specifically asked what I thought the best torque timing was with "knock out of the equation"
And I would NEVER discuss ignition advance without talking about a specific boost level. What do you think, that the optimal ignition advance is a 2d curve "under boost" without any changes whatsoever to the advance on different boost levels?
As I said, run the stock ignition advance if you think that it's the best torque numbers. It's your car, and your power loss.
07-17-2009 | 10:13 AM
#59
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Thank you!
It's been a while since I saw you on the forum?
I haven't measured the fuel. E85 is very common in Sweden and it seems to be good quality. Most tuned high performance machines around here run E85 and it seems to be no real variation of the fuel.
07-17-2009 | 08:47 PM
#60
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In fact, that's your whole topic of discussion: You want to experiment with MBT because you have a fuel that allows you to not be knock limited. I just continued on with this thought, because I'm interested in this as well. For some reason you're changing the subject or assumed I changed the subject. I should be banging my head.
I'm on your side: I agree we should strive to run more ignition advance to make most use of the air/fuel charge in the combustion chamber.