SteveB
08-18-2002, 11:29 AM
Tossing an idea out to any electronics type that wants to try something that my give WOT boosts without idle problems. I haven't got the time at present to try it:
Pass the TPS signal through an op-amp with approx gain of say 1.3 to boost the WOT voltage (with a limit of say 4.5v) which would let say 2/3 throttle give normal WOT voltages and the same output at idle as stock using a little voltage offset.
Ericdd
08-18-2002, 01:11 PM
I had a ford thunderbird and they actually made a part that did this. All you had to do was unplug your tps and plug this in line using the same connectors. I may still have it and I can find out who made it and if they can make one for us, or maybe it may work on ours by splicing. I do remember that from time to time it made my check engine light go on. I raised mine manually to .6 and 4.5 WOT. It seems to have some mild improvements, it pulls pretty hard in the mid to high RPM range. Any higher than .6 and I couldn't bring my idle down below 1000rpm.
Black200sxSER
08-19-2002, 03:33 AM
.6 will be making it run rich.and probably losing power....
93BlackBird
08-19-2002, 10:37 AM
I must be missing something here. the point is to have the computer think its at wot at 2/3 throttle? So if I went to real WOT the voltage would be higher than 4.5 correct? Would it know what to do at a voltage past 4.5?
Black200sxSER
08-19-2002, 12:11 PM
If it thinks it is at WOT, and it isnt...it is going to dump in more fuel...and run too rich. Too much fuel is less powerful..a leaner running motor produces more power, but too lean will detonate...so there is a balance needed.
Now it isnt a perfect reading like a wideband sensor..but when I had my car dyno'd a couple of weekends ago..they monitor A/F..on 3 runs, my car had an A/F of 11.2. Everyone else that i know around here said that is VERY rich, and could be what is casuing my low power output. This 11.2 is compared to my budys' 96 G20 with almost identical mods..and he has like 13.2 A/F on his dyno run. I am hearing 14.1 is ideal. Also, to add to this, when my car just sat and idled..it stank of too much fuel. So I know it was indeed on the rich side, even after a full tune up. So I tested my TPS voltage, and it was at .42 volts at idle. That is actually low to the specs of .45-.55 volts at idle. and at WOT it was set at 4 volts. the car dyno'd at 136 hp...:( thats bad mmmkay! (91 intake cam, HS gen4, Pr cai, GReddy,) Anyway...after speaking to a few local guys that tune turbos and such, and knowing that leaner produces more power..I took my very rich running .42 down to .35. After 2 trips out..wow, what a difference! The car "feels" like I think it should. Now, I havent taken it back to the dyno..so I cant say it made me back X amount of power..and now my A/F is XX.X perfect....but when it sits running..it doesnt stink like fuel anymore....I hope to be taking it back to the dyno one of these days...I had a friend take it to a local dyno day for me, so I wasnt able to "TUNE" on the dyno like I would have wanted to.. just a few thoughts on my particular situation..
Ericdd
08-19-2002, 06:30 PM
I bored my MAF a little bit so that probably compensated. I definetly didn't feel any power loss. It feels like It pulls harder around 3500-4500. I don't have an air/fuel guage so I can't tell for sure. .6v is really not alot if you consider .55v is normal, and at WOT it only reads around 4.3v. I wish I had a dyno.
Black200sxSER
08-19-2002, 06:36 PM
true.I forgot you said you bored out the TB
Ericdd
08-19-2002, 06:47 PM
NOT TB!!! MAF :) . I want to do the TB next maybe. does it mater what year you get it from. I want a second so I don't ruin my only one. I may also bore out my MAF more now that I compensated. I'd still like it a little lean, but I want to get a A/F guage before I go crazy.
thanks
Black200sxSER
08-19-2002, 06:49 PM
woops.yeah, I meant the MAF