Using HPP3 shift firmness to compensate for screenless MAF?
Thread Starter
Launching!
Joined: Dec 2003
Posts: 210
Likes: 0
Using HPP3 shift firmness to compensate for screenless MAF? Any idea if this would work? I've read many posts that said gutting the maf screen can lead to weak shifting- not shifting at all at WOT, etc etc etc.
TECH Fanatic
Joined: Sep 2002
Posts: 1,306
Likes: 0
From: DETROIT MUSCLE
Originally Posted by xjarayax
Any idea if this would work? I've read many posts that said gutting the maf screen can lead to weak shifting- not shifting at all at WOT, etc etc etc.
J
Thread Starter
Launching!
Joined: Dec 2003
Posts: 210
Likes: 0
Originally Posted by heyitsTaJay
here we go.....this is my opinion, and i am speaking only from what i have experienced. i ported and descreened my maf, and now my trans is giving me problems once and awhile. if you bump the shift firmness on a stock trans you may run into some problems depending on any mods you already have done. descreening should be ok, and you shouldnt have to bump shift firmness. also the "tuning" hpp3 does to the spark advance/fuel curve is for the crapper. i was told to leave that part alone. hpp3 is only good for a few things here and there.
J
J
Purely asking if using the HPP3 shift point firmness could compensate for why a lot of guys are having problems using ported/descreen MAFs
TECH Fanatic
Joined: Sep 2002
Posts: 1,306
Likes: 0
From: DETROIT MUSCLE
Originally Posted by xjarayax
I never said a word about using the "power programming" to up spark advance.
Purely asking if using the HPP3 shift point firmness could compensate for why a lot of guys are having problems using ported/descreen MAFs
Purely asking if using the HPP3 shift point firmness could compensate for why a lot of guys are having problems using ported/descreen MAFs
Thread Starter
Launching!
Joined: Dec 2003
Posts: 210
Likes: 0
Originally Posted by heyitsTaJay
i understand that you didnt say anything about that. i was giving some extra info that i recieved and thought i would pass on to others. i dont think that adding line pressure will compensate. happy?
Part throttle, but high throttle, is where the problem lies.
At WOT there should be full pressure applied. At part
throttle there are shift adaptation tables that allow a
very lazy shift and what the ported MAF does, is fool
you into using the low load, laziest setting when you
are applying substantial power through the shift. There
are several layers to "firmness". There is the base line
pressure, mechanical. Then this is down-regulated by
the PWM regulator. The PWM applied line pressure is
controlled by the PCM and the PCM "learns" how much to
apply by the "shift adaptation" process; there is a table
of how much time is "allowed" for a shift under various
loads/RPMs, and the PCM learns to just barely make it.
If the HPP3 zeroed those time values then it would always
shift hard at max PWM pressure. But I don't know what
the HPP3 does for "firmness", PWM max or the adaptation
or some combo or whatever. I know the Predator zeroes
the shift adaptation cells if you jack the shift time setting
negative, and has a separate "****" for the max PWM line
pressure.
Descreened should be a minor change to MAF fidelity
unless you have a very crooked intake tract. Ported is
the big error. 'Vettes and trucks have more of a bend,
hence airflow bias across the tract, than F-bodies.
I would certainly go with HPTuners over the retail price
of any handheld. Especially if you already own a laptop.
Used, there's a stronger temptation to get by on the
cheap - but from the look of the mod list you're willing
to pay to play, so pick a game you can win.
At WOT there should be full pressure applied. At part
throttle there are shift adaptation tables that allow a
very lazy shift and what the ported MAF does, is fool
you into using the low load, laziest setting when you
are applying substantial power through the shift. There
are several layers to "firmness". There is the base line
pressure, mechanical. Then this is down-regulated by
the PWM regulator. The PWM applied line pressure is
controlled by the PCM and the PCM "learns" how much to
apply by the "shift adaptation" process; there is a table
of how much time is "allowed" for a shift under various
loads/RPMs, and the PCM learns to just barely make it.
If the HPP3 zeroed those time values then it would always
shift hard at max PWM pressure. But I don't know what
the HPP3 does for "firmness", PWM max or the adaptation
or some combo or whatever. I know the Predator zeroes
the shift adaptation cells if you jack the shift time setting
negative, and has a separate "****" for the max PWM line
pressure.
Descreened should be a minor change to MAF fidelity
unless you have a very crooked intake tract. Ported is
the big error. 'Vettes and trucks have more of a bend,
hence airflow bias across the tract, than F-bodies.
I would certainly go with HPTuners over the retail price
of any handheld. Especially if you already own a laptop.
Used, there's a stronger temptation to get by on the
cheap - but from the look of the mod list you're willing
to pay to play, so pick a game you can win.
Thread Starter
Launching!
Joined: Dec 2003
Posts: 210
Likes: 0
Well, I already am in possession of the HPP3. I was using it for the rev limiter and shift point, gear change, tire size change, etc.
The alternative I could find that I could afford... (bought it for only $100- used)
The alternative I could find that I could afford... (bought it for only $100- used)
