TPS 4.1v @ WOT, does it matter?
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TPS 4.1v @ WOT, does it matter? If I push the TB open more it goes to 4.6v, but with my current setup it only hits 4.1v @ WOT. The PCM doesn't run my tranny so I'm not worried about that, can anyone think of any problems this might cause?
Re: TPS 4.1v @ WOT, does it matter? Terry,
Back in the TPI days, when the TPS first cam out, WOT was at 4.7 volts +/- .075 volts according to the shop manuals. I still always try to get around 4.63 - 4.7 volts (not over 4.7 even with the +/- .075). Even if A-TAP says 100% throttle I still try to get the voltage correct to ensure PCM sees full WOT.
I know that the LS1 still has the 4.7 volt max for WOT so I still believe the GM Engineers still use this voltage theory.
Hope this helps.
- Tom
<img src="graemlins/fluffy.gif" border="0" alt="[Fluffy]" />
[ February 22, 2002: Message edited by: Tom99SS ]</p>
Back in the TPI days, when the TPS first cam out, WOT was at 4.7 volts +/- .075 volts according to the shop manuals. I still always try to get around 4.63 - 4.7 volts (not over 4.7 even with the +/- .075). Even if A-TAP says 100% throttle I still try to get the voltage correct to ensure PCM sees full WOT.
I know that the LS1 still has the 4.7 volt max for WOT so I still believe the GM Engineers still use this voltage theory.
Hope this helps.
- Tom
<img src="graemlins/fluffy.gif" border="0" alt="[Fluffy]" />
[ February 22, 2002: Message edited by: Tom99SS ]</p>
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Re: TPS 4.1v @ WOT, does it matter? No it doesn't matter, I read the helms on this once and anything in excess of abou 3.8 (going off memory here) is considered WOT by the PCM. 4.7 gets you an SES light. If your blade isn't opening to 90 degrees that would matter in my opinion, but the volts, nope.
Re: TPS 4.1v @ WOT, does it matter? Dave,
I would have to disagree that 3.8 is enough, the blade being at 90 degrees I agree on. We realy should look into the PCM tables from ls1edit to see what voltage the tables are looking for. I know that going from 4.25 to 4.63 on my car helped at the track (13.4 - 13.2) with the only mods between the times was a home ported TB and the bump stop mod. 60' foot times where the same (2.0 - 2.05) but my MPH was up a little also.
Maybe I'am smoking something but I think this will help.
Just my .02
- Tom
[ February 22, 2002: Message edited by: Tom99SS ]</p>
I would have to disagree that 3.8 is enough, the blade being at 90 degrees I agree on. We realy should look into the PCM tables from ls1edit to see what voltage the tables are looking for. I know that going from 4.25 to 4.63 on my car helped at the track (13.4 - 13.2) with the only mods between the times was a home ported TB and the bump stop mod. 60' foot times where the same (2.0 - 2.05) but my MPH was up a little also.
Maybe I'am smoking something but I think this will help.
Just my .02
- Tom
[ February 22, 2002: Message edited by: Tom99SS ]</p>
Re: TPS 4.1v @ WOT, does it matter? If you have ASR, you can take up the slack by opening the black box (forget what it is called) that is in middle of the cable from the ASR module box to the end of the linkage at the TB.
Do a search on this board and ls1.com as it has been mentioned there many times. I don't remember what what exactly to do for either the ASR or non-ASR cars but I remember see posts.
Sorry I could not help out on this one.
- Tom
Do a search on this board and ls1.com as it has been mentioned there many times. I don't remember what what exactly to do for either the ASR or non-ASR cars but I remember see posts.
Sorry I could not help out on this one.
- Tom
Re: TPS 4.1v @ WOT, does it matter? I think...repeat, think...that as long as your going to closed loop PCM operation that youll be getting the max output. Atleast as far as the computer is concerned...the TB blade angle is a seperate issue. I have the LS1 scanmaster and it has a decimal that comes on when its operating under closed loop. And It usually doesnt take full throttle to get there. Ill have to pay attention closer next time I drive. I could be very wrong though. So dont take that as fact.
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Verdad Gallardo Re: TPS 4.1v @ WOT, does it matter? See if you can take some of the slack out from behind the gas pedal. Put a little spacer there to take up the slack. Ensure it does not effect closed throttle position. I think some have done it this way.
- Tom <img src="graemlins/gr_cheers.gif" border="0" alt="[cheers]" />
- Tom <img src="graemlins/gr_cheers.gif" border="0" alt="[cheers]" />
Re: TPS 4.1v @ WOT, does it matter? Yes, that does matter. It doesn't mean jack $hit your computer "thinks" is WOT, it's if the blade is actually opening completely giving true WOT. At 4.1 volts, your blade is not opening completely and it is hurting you. Way back in the days of first getting my car, I damaged my throttle cable on accident and it caused enough slack to bring me down to 4.1 volts. When I replaced the cable with a new one and tightened it up for 4.6 volts, I noticed a HUGE difference.
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Re: TPS 4.1v @ WOT, does it matter? Getting the TB blade to 90 degrees (actual) I think would be ideal @ WOT.
And, like was said, the pcm thinks anything over 4.0 volts is WOT.
But, anything over 4.75 V for 10 seconds sets a DTC P0123 according to the Helms.
Remember when you make a change like the bumpstop mod that some scan tools are only accurate to 0.1V , but if you're below 4.7V-no problem.
FWIW 90* actual blade angle on mine is 4.63V per voltmeter, 4.6V per Autotap.
And, like was said, the pcm thinks anything over 4.0 volts is WOT.
But, anything over 4.75 V for 10 seconds sets a DTC P0123 according to the Helms.
Remember when you make a change like the bumpstop mod that some scan tools are only accurate to 0.1V , but if you're below 4.7V-no problem.
FWIW 90* actual blade angle on mine is 4.63V per voltmeter, 4.6V per Autotap.
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From: Derby, KS
Re: TPS 4.1v @ WOT, does it matter? [quote]Originally posted by Damian:
<strong>Yes, that does matter. It doesn't mean jack $hit your computer "thinks" is WOT, it's if the blade is actually opening completely giving true WOT. At 4.1 volts, your blade is not opening completely and it is hurting you. Way back in the days of first getting my car, I damaged my throttle cable on accident and it caused enough slack to bring me down to 4.1 volts. When I replaced the cable with a new one and tightened it up for 4.6 volts, I noticed a HUGE difference.</strong><hr></blockquote>
Damian I've seen TB blades at 90 degrees and getting a voltage of 4.1, and I've seen them at less than 90 degrees getting a similar voltage. The voltage Terry or anybody else is getting is not going to tell you if it's open to 90 degree or not. These will though <img src="gr_eek2.gif" border="0">
If your blade is opening to 90 degrees and the volts are over 4.0, any more voltage doesn't do anything to performance except for a possible placebo effect on the owner/driver. This is more urban legend......
<strong>Yes, that does matter. It doesn't mean jack $hit your computer "thinks" is WOT, it's if the blade is actually opening completely giving true WOT. At 4.1 volts, your blade is not opening completely and it is hurting you. Way back in the days of first getting my car, I damaged my throttle cable on accident and it caused enough slack to bring me down to 4.1 volts. When I replaced the cable with a new one and tightened it up for 4.6 volts, I noticed a HUGE difference.</strong><hr></blockquote>
Damian I've seen TB blades at 90 degrees and getting a voltage of 4.1, and I've seen them at less than 90 degrees getting a similar voltage. The voltage Terry or anybody else is getting is not going to tell you if it's open to 90 degree or not. These will though <img src="gr_eek2.gif" border="0">
If your blade is opening to 90 degrees and the volts are over 4.0, any more voltage doesn't do anything to performance except for a possible placebo effect on the owner/driver. This is more urban legend......
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Re: TPS 4.1v @ WOT, does it matter? Terry i fyou are seeing differences from manually opening the T-body all the way and from stepping on the gas I would definitely address it.
Also with the TPS voltage while you are at it you may as well fix that too. Be careful with grinding the throttle stop though and dont go too far.
Cheers,
Chris
Also with the TPS voltage while you are at it you may as well fix that too. Be careful with grinding the throttle stop though and dont go too far.
Cheers,
Chris
