Stage X X X X X
05-18-2003 | 05:21 PM
#61
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Chad,
My point was that your car and the other gentlemans car drive proper, but that the mapping is off or the other car had some huge boost/mechanical advantage at the torque area to require huge changes in fueling.
As you have pointed out, your car drives ok, then the only conclusion can be that the mapping is way off, or the measuring of the A/F and other parameters is not accurate.
As I have said before, making changes to these engines and remapping the ECU, is not as easy as made out by some. After all, all of the information is "reverse engineered", and hoped that the whole control is known. Most of the time, it is not. I cannot understand how the fueling can be that far off, if the software is known and can be adjusted properly. At no time can you have fueling so far off if known.
I do not know anything about the Porsche program, but I do know about how the map should look. If the fuel mapping is done in milisec's it should be fairly flat across the RPM curve at the same MAP/air volume, dropping off at the higher RPM's. If the fuel map is based on engine VE, it should be very flat and drop off at the upper RPM's. Again, unless there's some huge change in VE in the torque area, (the horrible to drive engine), the fueling should be very consistant. The only thing that cahnges this is DET. If you have to fuel the engine to stop DET, then you are better to pull back boost and or timing. An over fueled engine is has less performance than a lower boosted engine, or an engine with less timing. As the computer can make these changes very quickly, in comparision to an engine having to burn off extra unwanted fuel.
My advice is to understand exactly what is been done and how. Then make the choice to continue with the factory system,(with concessions) or change to a alternative. It must be said that if you are happy with the results, that is all that matters. Its your movie, and you are the star. I can tell you this though, the difference between cars that have been remapped using the factory system, and those with a alternative system mapped properly is huge.
I think what you may want to look at is the "InterLink" system by Linkelectro Systems. I'm not sure if they do the Porsche, but I know they have these for some of the Nissan V8 etc. Its a system that allows full control over the engine when you want it, but still leaves the factory system in place to control the ABS etc. I don't know to much about it, but the user can tune this just like an aftermarket EFI system. The factory EFI still thinks its driving the Injectors, Ignition, O2 etc, etc. I think its a really powerful intercept system. What I like about this type of system, is the other things which need to be left alone can be driven by the factory EFI, but the user now has complete control and understanding of how to control the engine. Smog should be no problem, as the factory can control this area of the map, as long as the engine mechanicals are not out of spec to far. I don't have any further info, but if you contact Link, they should be able to help you.
My point was that your car and the other gentlemans car drive proper, but that the mapping is off or the other car had some huge boost/mechanical advantage at the torque area to require huge changes in fueling.
As you have pointed out, your car drives ok, then the only conclusion can be that the mapping is way off, or the measuring of the A/F and other parameters is not accurate.
As I have said before, making changes to these engines and remapping the ECU, is not as easy as made out by some. After all, all of the information is "reverse engineered", and hoped that the whole control is known. Most of the time, it is not. I cannot understand how the fueling can be that far off, if the software is known and can be adjusted properly. At no time can you have fueling so far off if known.
I do not know anything about the Porsche program, but I do know about how the map should look. If the fuel mapping is done in milisec's it should be fairly flat across the RPM curve at the same MAP/air volume, dropping off at the higher RPM's. If the fuel map is based on engine VE, it should be very flat and drop off at the upper RPM's. Again, unless there's some huge change in VE in the torque area, (the horrible to drive engine), the fueling should be very consistant. The only thing that cahnges this is DET. If you have to fuel the engine to stop DET, then you are better to pull back boost and or timing. An over fueled engine is has less performance than a lower boosted engine, or an engine with less timing. As the computer can make these changes very quickly, in comparision to an engine having to burn off extra unwanted fuel.
My advice is to understand exactly what is been done and how. Then make the choice to continue with the factory system,(with concessions) or change to a alternative. It must be said that if you are happy with the results, that is all that matters. Its your movie, and you are the star. I can tell you this though, the difference between cars that have been remapped using the factory system, and those with a alternative system mapped properly is huge.
I think what you may want to look at is the "InterLink" system by Linkelectro Systems. I'm not sure if they do the Porsche, but I know they have these for some of the Nissan V8 etc. Its a system that allows full control over the engine when you want it, but still leaves the factory system in place to control the ABS etc. I don't know to much about it, but the user can tune this just like an aftermarket EFI system. The factory EFI still thinks its driving the Injectors, Ignition, O2 etc, etc. I think its a really powerful intercept system. What I like about this type of system, is the other things which need to be left alone can be driven by the factory EFI, but the user now has complete control and understanding of how to control the engine. Smog should be no problem, as the factory can control this area of the map, as long as the engine mechanicals are not out of spec to far. I don't have any further info, but if you contact Link, they should be able to help you.
05-19-2003 | 03:11 PM
#62
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Joined: Nov 2001
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From: $F Bay Area
</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by cjv:
<strong>Dave Coleman from Excellence and Alex Pfeiffer a National Drift Champion ran the car for eight runs. Dave Coleman took The Top Time of the Day. A full second plus ahead of Alex and one and a half seconds ahead the next car which was running Hoosiers. Actually Dave and Alex combined had the seven best times. Dave had the four fastest times of the day followed by Alex with the next three fastest.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Yeah Dave is really fast. He races a 914 on Goodyear slicks and totally kicked everyone's asses in the Golden Gate Region SCCA autocrosses last year. I should've gone up to Sonoma yesterday to check it out, damb!
<strong>Dave Coleman from Excellence and Alex Pfeiffer a National Drift Champion ran the car for eight runs. Dave Coleman took The Top Time of the Day. A full second plus ahead of Alex and one and a half seconds ahead the next car which was running Hoosiers. Actually Dave and Alex combined had the seven best times. Dave had the four fastest times of the day followed by Alex with the next three fastest.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Yeah Dave is really fast. He races a 914 on Goodyear slicks and totally kicked everyone's asses in the Golden Gate Region SCCA autocrosses last year. I should've gone up to Sonoma yesterday to check it out, damb!
05-19-2003 | 06:00 PM
#63
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CJV. I can only add my knowledge that I have gained from speaking to many people about Aftermarket EFI systems like Motec, DTA, etc. I think I may have spoken to you about thsi once before as well. It is my understanding (see that disclaimer?) that while a motec or like system is not specifically what the EPA would call smog legal, an owner of such a system could simply reprogram the system when needed to pass smog. A visual check is a worry for many as well. The computer is behind your rear seat in the 996... Doesnanyone have any info that says technicians are supposed to look for this computer visually? I doubt this strongly. If a programmable system like motec, or the DTA I will be using is changable to add MORE power, why couldn't iit be temporarily downloaded witha good clean program to pass smog? Who would be able to tell the difference? I have passed only one test in San Diego on my 81, and he looked ofr the gas cap, the cats, an air pump, and the timing. Well, if you have a cat on the TT, and the program is OEM on timing, then I would think that you would pass with flying colors. Is it worth the effort ot have the car tuned for this additional program to pass every two years or whenever? That is up to the decision maker.
05-20-2003 | 03:08 AM
#65
Three Wheelin'
Joined: Feb 2003
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Its my understanding that you can get any EFI system to pass the CARB cert., as long as ceratin functions are inoperative. No ability to change mapping after testing and certification etc. I believe this is how Canepa Design have certified the 959 and got the performance NO one else has after testing. A side note here, the factory used the stock ECU to certify a 959, it failed and a 911SC could out perform it. I understand the lab in Texas, although passing the test, the car has no power.
As for the Interlink, it is a very powerful and smart Intercept system, but is reaslly a standalone EFI system fully programmable by the user. It allows the factory system to control all of the other functions, ABS, etc., but takes over the control of the Injectors, Ignition, Boost whenever you want to. It has special hardware that takes control of the factory ECU, giving the factory ECU information which the factory ECU thinks is the Injectors etc. This way the factory ECU still thinks it is controlling the engine.
I only understand a little of how it works. You would be advised to call Link and ask them. I do know that they have done some of the new Nissan V8 SUV's with this system for Saudi customers who have had them twin turbo'ed. Huge HP over 900, and those cars have everything controlled by the ECU.
As for the Interlink, it is a very powerful and smart Intercept system, but is reaslly a standalone EFI system fully programmable by the user. It allows the factory system to control all of the other functions, ABS, etc., but takes over the control of the Injectors, Ignition, Boost whenever you want to. It has special hardware that takes control of the factory ECU, giving the factory ECU information which the factory ECU thinks is the Injectors etc. This way the factory ECU still thinks it is controlling the engine.
I only understand a little of how it works. You would be advised to call Link and ask them. I do know that they have done some of the new Nissan V8 SUV's with this system for Saudi customers who have had them twin turbo'ed. Huge HP over 900, and those cars have everything controlled by the ECU.
05-24-2003 | 02:28 AM
#67
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Didn't you say you had a second engine a while back that you were going to play with
?
</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by cjv:
<strong>The car is substantially complete. I will be picking it up tomorrow. Time to enjoy. <img border="0" alt="[bigbye]" title="" src="graemlins/xyxwave.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">
?</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by cjv:
<strong>The car is substantially complete. I will be picking it up tomorrow. Time to enjoy. <img border="0" alt="[bigbye]" title="" src="graemlins/xyxwave.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">
05-24-2003 | 01:50 PM
#69
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Joined: Jul 2002
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From: Bahrain
cjv, congrats on finishing the car,for now at least!! I remember last summer and have been following-up every post and hey, I'm glad it's over and happy for you that you'll finally, get to enjoy the car, hope it's all you imagined it to be <img border="0" alt="[thumbsup]" title="" src="graemlins/bigok.gif" /> Can't wait to read the article and see the numbers, I'm sure it's one hell of a ride 
05-24-2003 | 02:44 PM
#70
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Where and when are going to go? I would love to see it run the 1/4mile
</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by cjv:
<strong>sharkster,
Yes, there is a second motor presently being built. <img border="0" alt="[sleep]" title="" src="graemlins/sleep.gif" />
adrial,
Now the fun begins. Just need to learn the car and proceed slowly. We did an Auto X last Sunday. It was a lot of fun. It surprised me in addition lot of other people. I guess turbo's are not suppose to do that well against the other competition.
Planning on obtaining some 0-60 and 1/4 mile times next week followed by a shake down at Thunder Hill. Found a few minor bugs ... nothing serious.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">
? I would love to see it run the 1/4mile</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by cjv:
<strong>sharkster,
Yes, there is a second motor presently being built. <img border="0" alt="[sleep]" title="" src="graemlins/sleep.gif" />
adrial,
Now the fun begins. Just need to learn the car and proceed slowly. We did an Auto X last Sunday. It was a lot of fun. It surprised me in addition lot of other people. I guess turbo's are not suppose to do that well against the other competition.
Planning on obtaining some 0-60 and 1/4 mile times next week followed by a shake down at Thunder Hill. Found a few minor bugs ... nothing serious.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">
05-25-2003 | 01:46 AM
#72
Race Car
Joined: Nov 2001
Posts: 4,089
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From: $F Bay Area
</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by cjv:
<strong>If all goes well the car will be at Infineon Raceway at Sears Point on Wednesday night May 28th. Part II of our tests. We will be checking the sixty foot time, 0-60 mph and 1/4 mile. Dave Coleman will be driving.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">I'm going to see that!
<strong>If all goes well the car will be at Infineon Raceway at Sears Point on Wednesday night May 28th. Part II of our tests. We will be checking the sixty foot time, 0-60 mph and 1/4 mile. Dave Coleman will be driving.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">I'm going to see that!
05-26-2003 | 11:04 AM
#73
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Joined: May 2002
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From: Orange, CA
Hey Chad,
Awhile back after you put on the new wheels/tires, you talked about how the car was twitchy (don't remember your exact words)at speed. Did you make some adjustments (alignment or otherwise) to solve this problem? I imagine that in an autocross situation this would not be such a big deal. But, since you are working out track dates, I just wondered how things were going in the higher speed handling department. I wish I could see your next test in person. Reading about it is exciting, but nothing beats a real time experience!! Good luck and keep on keep'n on!
Bob
Awhile back after you put on the new wheels/tires, you talked about how the car was twitchy (don't remember your exact words)at speed. Did you make some adjustments (alignment or otherwise) to solve this problem? I imagine that in an autocross situation this would not be such a big deal. But, since you are working out track dates, I just wondered how things were going in the higher speed handling department. I wish I could see your next test in person. Reading about it is exciting, but nothing beats a real time experience!! Good luck and keep on keep'n on!
Bob
05-26-2003 | 04:27 PM
#74
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Damn you! Mt Hamilton is right near me and I go up that road every so often in mine because it's a lot of fun. Next time, tell me lol... I want to see that beast.
</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by cjv:
<strong>Bob,
The caster was set at 6 degrees, the toe in at 1/16 inch and the camber at 2 degrees. The car was corner balanced and aligned. It was then taken to the Auto X and a run was made. After which Rob King made some adjustments to the JRZ system. Two more runs were made and the JRZ's were adjusted further. In conjunction the air pressures for the Michelin Pilot Sport Cup 265/35ZR18's (front) and 315/40ZR18's (rear) were gradually lowered. Final adjustments were made to tire pressure only. When they cooled the fronts were 33.5 psi and the rears were 35.5 psi. The times for each run progressively came down although not by a lot for each successive run.
Dave Coleman described the handling of the car as the closest thing he has ever experienced to a shift kart. He was pleasantly surprised given the weight of the car. <img border="0" title="" alt="[Eek!]" src="eek.gif" /> The draw back to the car (if you want to call it a draw back) is the power. Judicious application of power is mandatory if you expect to stay on course in a turn of any kind. In one long sweeper I could hear other cars with a constant acceleration tone as they passed. I could destinctly hear Dave constantly feathering the throttle through the same turn as he passed.
As for my experiences, I took the car up to Mount Hamilton road. It did indeed handle like a kart. Very responsive, firm, quick, glued to the road feeling. On the highway it is also very responsive. A little input to the wheel provides a very quick response. It tends to track a little in highway grooves/ruts where a little extra effort is required. On highway clover leafs it is heaven to drive. As for your question about high speed handling .... I do not know as of yet. I will restrict this test to the track as where I live it cannot be conducted safely (my opinion). </strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">
lol... I want to see that beast.</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by cjv:
<strong>Bob,
The caster was set at 6 degrees, the toe in at 1/16 inch and the camber at 2 degrees. The car was corner balanced and aligned. It was then taken to the Auto X and a run was made. After which Rob King made some adjustments to the JRZ system. Two more runs were made and the JRZ's were adjusted further. In conjunction the air pressures for the Michelin Pilot Sport Cup 265/35ZR18's (front) and 315/40ZR18's (rear) were gradually lowered. Final adjustments were made to tire pressure only. When they cooled the fronts were 33.5 psi and the rears were 35.5 psi. The times for each run progressively came down although not by a lot for each successive run.
Dave Coleman described the handling of the car as the closest thing he has ever experienced to a shift kart. He was pleasantly surprised given the weight of the car. <img border="0" title="" alt="[Eek!]" src="eek.gif" /> The draw back to the car (if you want to call it a draw back) is the power. Judicious application of power is mandatory if you expect to stay on course in a turn of any kind. In one long sweeper I could hear other cars with a constant acceleration tone as they passed. I could destinctly hear Dave constantly feathering the throttle through the same turn as he passed.
As for my experiences, I took the car up to Mount Hamilton road. It did indeed handle like a kart. Very responsive, firm, quick, glued to the road feeling. On the highway it is also very responsive. A little input to the wheel provides a very quick response. It tends to track a little in highway grooves/ruts where a little extra effort is required. On highway clover leafs it is heaven to drive. As for your question about high speed handling .... I do not know as of yet. I will restrict this test to the track as where I live it cannot be conducted safely (my opinion).
</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">
05-26-2003 | 07:39 PM
#75
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Chad,
When yo get ready to do a few mild high speed tests I may know someone that would be thrilled to help out!
</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">
As for your question about high speed handling .... I do not know as of yet. I will restrict this test to the track as where I live it cannot be conducted safely (my opinion).
</font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">I know a perfect road and possibly a driver as well. Fuel cell installed yet?
R <img border="0" alt="[cheers]" title="" src="graemlins/beerchug.gif" />
When yo get ready to do a few mild high speed tests I may know someone that would be thrilled to help out!
</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">
As for your question about high speed handling .... I do not know as of yet. I will restrict this test to the track as where I live it cannot be conducted safely (my opinion).
</font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">I know a perfect road and possibly a driver as well. Fuel cell installed yet?
R <img border="0" alt="[cheers]" title="" src="graemlins/beerchug.gif" />