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A dyno was done on my car before anything was put on to make sure my engine was running fine.I had the dyno done at Speedworks and they took my car up to 6200 RPMS.At around 5400 rpms, and 76MPH i got execive Pinging.The curve on the dyno show a normal climb, then a weird drop at 5400, then a sharp drop at 6200.
Here are the problems with that.
I had a dyno done at speedwork once before a long time ago... about 1 yr ago actually, and I got 185HP @85 MPH.
However there is a good explanation to what is happening. When i had the first dyno done last year, it was with a Jet Chip. The first run was made with the Jet Chip, and the second was done without it. However we all know that pulling out a Jet Chip isn't going to reset anything right away.
I can't remember, but i am sure the Jet chip compinsates for thermostat, changes shift points and raises the limiters.
I also had another problem back then which was the fact that i had changed the gears. The Dyno shows that i hit 185HP @85Miles an hour and i got cut off, at 4200RPMs. It hit my speed limiter early because i had my gears changed. That particular run was done in 3rd gear and Greg at Speedworks told me that he had made changes in the dyno to compinsate for my gears.
Now back to the present situation. With all that said, This time they made the runs in 2nd gear.
What Bill believes happend is that this time my car hit the rev limiter at 5400 rpms (As it should) and cut the fuel off which would explain the excessive pinging. We drove the car and drove it in first and if any of you have done this before, you will notice that in 1st gear that the fuel is cut off right around 5400 RPMS, at this point you can hear the car as if it was in nuetral (fuel is cut off) and then it just hangs there as it (which would explain the drop in the curve after 5400RPMS) revs up to 6200RPMS at which point HP and torque dropps (which would explain the sharp drop at 6200RPMS).
Bill is pretty condfident that my car is not pinging, but that it is just hitting the rev limiter. However not to take any risks, he wants to be sure he is right without a doubt and wanted to do the cal on my pcm to raise the rev and speed limiter. IF he raises the limiter to 6000RPMS, then the new dyno should show pinging after i hit 6000RPMS. If i still get pinging at 5400RPMS, then there may be an issue.
He is also making sure that the new cal tells my PCM that i have 160 deg thermostat and 3.42 gears.
Right now my car is running very hot. I used to have a 180 thermostat in and i thought it ran pretty hot then, well its running even hotter now with the 160 stat. He said that changing the thermostat to 160 and not calibrating your PCM won't do any good... infact it can make your car run hotter.
Here is why: Your PCM is programmed to open up at 195 (stock thermostat) and allow coolant to run through the engine and radiator. Your PCM is also programmed to turn your fans on at a certain temp 210 i think. Normally the coolant gets time to cool down in the radiator because the fan is on and then the cooled down coolant runs through the engine making it cooler.
However with the 160 thermostat. The pcm opens the coolant up at 160 letting coolant run through the engine. However the PCM is still programmed to only allow the fans to turn on at 210 which means from the time that my car is 160 till i reaches 210, the coolant is not being cooled down in the radiator because the fans aren't on. So basically i am running hot coolant through my engine.
Make sense? Of course when he explained it to me i had my doubts cause i remember when i had the 180 stat in, my car wasn't running as hot, but then i remembered i had the jet chip inside my car which reprogrammed the pcm to compinsate for a 160/180 thermostat. The Jet Chip isn't in my car anymore so now my car is opening up at 160 and not being cooled till 210.
The gears are also messing things up. Because i originally had 3.08 gears and now i have 3.42 gears, i keep hitting the rev and speed limiters earlier than what i am supposed to be hitting it at. On the way back from Maryland from the shoot out i tried to see how far off i was in my milage reading. Well i found that my trip meter showed me hitting 1 mile mark 1/10 of a mile before i actully hit a mile. So since i have 40000 miles on my car its safe to say that it is very possible that i have 4000 mile on my car more than what it really has. WHICH SUCKS Cause it means i would still be under waranty if i hadn't changed my gears. UGGGH.
Anyways...
BIll does not want to slap a blower on a car that is pinging, cause he doesn't want my car to blow up [img]smile.gif[/img] i am glad he doens't want to do that either.
SO he got the cal from the GM engineer and they tried it, and well.. .my car wouldn't even start. They looked over the code and the Engineer knows exactly what is wrong, but before he makes the change, he wants to consult another engineer who happens to be on vacation about the differences with a 2000 PCM and other years. He wants to learn everything there is to know about an Fbody V6 PCM. Bill said he will have the new cal on monday.
For the time being, Bill went and downloaded the latest cal from GM for a 2000 firebird and put my car back to what it was. My car is running fine with no problems [img]smile.gif[/img] Probably even better since I now have the latest CAL. I bought my car in 1999 even though it is a 2000 and i am sure i had V1.0 of whatever Cal they had for the 2000 Firebird back then. JUST Thought i would mention that so you guys don't think he broke my car [img]smile.gif[/img]
Bill is confident that the new cal will work.
In the mean time he took all the mesurments he needs and he is now working on the bracket and the duct work [img]smile.gif[/img]
Regardless of hicups which should be expected, things are moving forward.
[ July 18, 2002: Message edited by: BATMAN ]</p>
Here are the problems with that.
I had a dyno done at speedwork once before a long time ago... about 1 yr ago actually, and I got 185HP @85 MPH.
However there is a good explanation to what is happening. When i had the first dyno done last year, it was with a Jet Chip. The first run was made with the Jet Chip, and the second was done without it. However we all know that pulling out a Jet Chip isn't going to reset anything right away.
I can't remember, but i am sure the Jet chip compinsates for thermostat, changes shift points and raises the limiters.
I also had another problem back then which was the fact that i had changed the gears. The Dyno shows that i hit 185HP @85Miles an hour and i got cut off, at 4200RPMs. It hit my speed limiter early because i had my gears changed. That particular run was done in 3rd gear and Greg at Speedworks told me that he had made changes in the dyno to compinsate for my gears.
Now back to the present situation. With all that said, This time they made the runs in 2nd gear.
What Bill believes happend is that this time my car hit the rev limiter at 5400 rpms (As it should) and cut the fuel off which would explain the excessive pinging. We drove the car and drove it in first and if any of you have done this before, you will notice that in 1st gear that the fuel is cut off right around 5400 RPMS, at this point you can hear the car as if it was in nuetral (fuel is cut off) and then it just hangs there as it (which would explain the drop in the curve after 5400RPMS) revs up to 6200RPMS at which point HP and torque dropps (which would explain the sharp drop at 6200RPMS).
Bill is pretty condfident that my car is not pinging, but that it is just hitting the rev limiter. However not to take any risks, he wants to be sure he is right without a doubt and wanted to do the cal on my pcm to raise the rev and speed limiter. IF he raises the limiter to 6000RPMS, then the new dyno should show pinging after i hit 6000RPMS. If i still get pinging at 5400RPMS, then there may be an issue.
He is also making sure that the new cal tells my PCM that i have 160 deg thermostat and 3.42 gears.
Right now my car is running very hot. I used to have a 180 thermostat in and i thought it ran pretty hot then, well its running even hotter now with the 160 stat. He said that changing the thermostat to 160 and not calibrating your PCM won't do any good... infact it can make your car run hotter.
Here is why: Your PCM is programmed to open up at 195 (stock thermostat) and allow coolant to run through the engine and radiator. Your PCM is also programmed to turn your fans on at a certain temp 210 i think. Normally the coolant gets time to cool down in the radiator because the fan is on and then the cooled down coolant runs through the engine making it cooler.
However with the 160 thermostat. The pcm opens the coolant up at 160 letting coolant run through the engine. However the PCM is still programmed to only allow the fans to turn on at 210 which means from the time that my car is 160 till i reaches 210, the coolant is not being cooled down in the radiator because the fans aren't on. So basically i am running hot coolant through my engine.
Make sense? Of course when he explained it to me i had my doubts cause i remember when i had the 180 stat in, my car wasn't running as hot, but then i remembered i had the jet chip inside my car which reprogrammed the pcm to compinsate for a 160/180 thermostat. The Jet Chip isn't in my car anymore so now my car is opening up at 160 and not being cooled till 210.
The gears are also messing things up. Because i originally had 3.08 gears and now i have 3.42 gears, i keep hitting the rev and speed limiters earlier than what i am supposed to be hitting it at. On the way back from Maryland from the shoot out i tried to see how far off i was in my milage reading. Well i found that my trip meter showed me hitting 1 mile mark 1/10 of a mile before i actully hit a mile. So since i have 40000 miles on my car its safe to say that it is very possible that i have 4000 mile on my car more than what it really has. WHICH SUCKS Cause it means i would still be under waranty if i hadn't changed my gears. UGGGH.
Anyways...
BIll does not want to slap a blower on a car that is pinging, cause he doesn't want my car to blow up [img]smile.gif[/img] i am glad he doens't want to do that either.
SO he got the cal from the GM engineer and they tried it, and well.. .my car wouldn't even start. They looked over the code and the Engineer knows exactly what is wrong, but before he makes the change, he wants to consult another engineer who happens to be on vacation about the differences with a 2000 PCM and other years. He wants to learn everything there is to know about an Fbody V6 PCM. Bill said he will have the new cal on monday.
For the time being, Bill went and downloaded the latest cal from GM for a 2000 firebird and put my car back to what it was. My car is running fine with no problems [img]smile.gif[/img] Probably even better since I now have the latest CAL. I bought my car in 1999 even though it is a 2000 and i am sure i had V1.0 of whatever Cal they had for the 2000 Firebird back then. JUST Thought i would mention that so you guys don't think he broke my car [img]smile.gif[/img]
Bill is confident that the new cal will work.
In the mean time he took all the mesurments he needs and he is now working on the bracket and the duct work [img]smile.gif[/img]
Regardless of hicups which should be expected, things are moving forward.
[ July 18, 2002: Message edited by: BATMAN ]</p>
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