WOT
#11
my car feels the same way sometimes
but i thought it was because the tranny didnt downshift when floored
it downshifts if you give it halfway depressed
thats what i thought happens
but i thought it was because the tranny didnt downshift when floored
it downshifts if you give it halfway depressed
thats what i thought happens
#13
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Something else you might try is checking how fast the throttle butterfly valve opens in relation to how far down you press the pedal. It'* not necessarily an even linear motion.
A lot of car companies try a little trick to make their cars feel quicker, and that is to design the cam on the throttle linkage to open the throttle valve almost all the way even though you've only pressed down on the pedal a little bit. So when you take off from a light, you think, 'man, this is a quick machine!' Then when you do floor it, there'* really not much throttle left.
Try having a beautiful blonde assistant in a bikini press down on your pedal whilst you look down the throttle body, and see how much it opens in relation to how far she is pushing on the pedal. You might be surprised.
A lot of car companies try a little trick to make their cars feel quicker, and that is to design the cam on the throttle linkage to open the throttle valve almost all the way even though you've only pressed down on the pedal a little bit. So when you take off from a light, you think, 'man, this is a quick machine!' Then when you do floor it, there'* really not much throttle left.
Try having a beautiful blonde assistant in a bikini press down on your pedal whilst you look down the throttle body, and see how much it opens in relation to how far she is pushing on the pedal. You might be surprised.
#15
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If its running lean the computer will richen the mixture very quickly... Unless you are having sensor trouble or fuel delievery problems
Healthy 02'* for an L67 are 880-930, 930 being richer and 880 being leaner. 880 will give you the most power if you are getting no KR, while 930 will rid of some KR, and we like to keep them at more like 910-940 just to be safe, because lean can really mess things up. (Like blow chunks out of pistons and stuff). So we autotapped the SSEi and it was seeing 02'* of 845 with the factory PCM. This is very dangerous for the engine because it is runny pretty lean which as I said earlier can really screw things up, and it was causing about 5 degrees of kr, robbing the car of 10-15hp. Now hooking up the Mini-AFC to the SSEi and putting it at 105% (100% is as if it isn't there) the 02'* went up to a healthy 915, so we just left it at 105% because it completely rid of all KR we were getting, plus it was in the safe range now. The GTP on the other hand runs VERY VERY rich if we let the computer control it. With the mini-afc set at 88% we were seeing 02'* in the 980-990 range, and it is 12% lower than what the PCM was commanding, we fixed the lean condition in the SSEi by only going 5% richer, and it gained about 60, so that tells you it is VERY rich if it is 12% less and still at 980-990. So we turned the AFC down to 80% and were still seeing 02'* of 955-965, which is still rich. Finally we just turned it down to 78% (where it is currently) because the 02'* just wouldn't come down. (They are still 955-965) What this says is even when we are commanding just 78% of the air fuel ratio the PCM is commanding the car is still running fairly rich, so basically what the PCM does to adjust the air-fuel ratio sucks. Do not assume that because the computer is controlling your air-fuel ratio that it is anywhere near it should be, especially if you are modded, because chances are, it isn't.
#16
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dbtk,
What do you mean by autotapped? You have to have another device to read the air/fuel mixture?
Or will the mini-AFC display the current mixture?
What do you mean by autotapped? You have to have another device to read the air/fuel mixture?
Or will the mini-AFC display the current mixture?
#17
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AutoTap is a device that you connect to your car (under the dashboard) and it communicates with your PCM and gives you loads of information on what the sensors are telling the PCM and what the PCM is doing. This can be a handheld unit that only reads trouble codes or it can be a connector that allows you to connect your PCM to a laptop and really see what'* going on i real-time through the AutoTap software.
Note: This wonderful device is not cheap, and if you are going to buy one make sure your car is ODB2 or ODB1 to get the proper connector (I think cars after '95 are ODB2).
Also, devices like these only READ form the PCM, you can not change any of the operating values, only clear trouble codes, so get those dreams out of your head
The Mini-AFC ( http://www.zzperformance.com/zzp/pro...e/mini_afc.htm ) does not display anything as you can see in the pic at the link.
I was able to get an AutoTap unit for review when i worked for PC Magazine and my friends were able to read their Bonnies' PCMs (a '95 and a '97 with ODB2)
But mine'* a '93 and I couldn't connect it cus it'* ODB1 and the connector is diferent
Note: This wonderful device is not cheap, and if you are going to buy one make sure your car is ODB2 or ODB1 to get the proper connector (I think cars after '95 are ODB2).
Also, devices like these only READ form the PCM, you can not change any of the operating values, only clear trouble codes, so get those dreams out of your head
The Mini-AFC ( http://www.zzperformance.com/zzp/pro...e/mini_afc.htm ) does not display anything as you can see in the pic at the link.
I was able to get an AutoTap unit for review when i worked for PC Magazine and my friends were able to read their Bonnies' PCMs (a '95 and a '97 with ODB2)
But mine'* a '93 and I couldn't connect it cus it'* ODB1 and the connector is diferent
#18
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Wait until the Mini-AFC 2.0, which should be released to the public soon. The original tends to burn out, as least it did for one of our members.
#19
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A lot of car companies try a little trick to make their cars feel quicker, and that is to design the cam on the throttle linkage to open the throttle valve almost all the way even though you've only pressed down on the pedal a little bit. So when you take off from a light, you think, 'man, this is a quick machine!' Then when you do floor it, there'* really not much throttle left.
Sorry for the interruption