3.23-3.73
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Registered User
Joined: Aug 2002
Posts: 2,325
From: BC
3.23-3.73
Posted this in the drivetrain forum earlier (wasnt thinking straight 
):
I know how to calibrate the speedo, but will I need to change my shift points if I change gears?
If I do by how much? Is it safe to do the following for the appropriate shift tables (because they seem to by Throttle % & MPH for the shift points)
3.73 / 3.23 = 1.155
DECREASE (edit) all shift points to approximatly 15% more than what they are right now? (Multiply them by 3.23/3.73=0.866)
):I know how to calibrate the speedo, but will I need to change my shift points if I change gears?
If I do by how much? Is it safe to do the following for the appropriate shift tables (because they seem to by Throttle % & MPH for the shift points)
3.73 / 3.23 = 1.155
DECREASE (edit) all shift points to approximatly 15% more than what they are right now? (Multiply them by 3.23/3.73=0.866)
Last edited by TobyZ28; Mar 20, 2006 at 07:30 PM.
Registered User
Joined: Jul 2003
Posts: 700
From: Upstate New York
Re: 3.23-3.73
I went from 2.73s to 3.42's to 3.73s to 3.73's with GV OD (.78)
which gives me 2.91 for the highway and I never changed any of the shift points except for moving up 1-2 shift at 0 TP or low throttle from 10 to 14 with a high at 100% TP of 39 vs 31.
That was so i'd have more time to hang it in 1st.
And I only made this change recently and am quite happy with it.
I'd say see how it works before making changes so you
know what it feels like stock.
which gives me 2.91 for the highway and I never changed any of the shift points except for moving up 1-2 shift at 0 TP or low throttle from 10 to 14 with a high at 100% TP of 39 vs 31.
That was so i'd have more time to hang it in 1st.
And I only made this change recently and am quite happy with it.
I'd say see how it works before making changes so you
know what it feels like stock.
Registered User
Joined: Jul 2003
Posts: 700
From: Upstate New York
Re: 3.23-3.73
The shift points are set by the engine rpms and TP, not by changing the gear ratio.
Numerically higher gears will make the car reach the set rpm shift point sooner.
I'm presuming you have LT-1 Edit which I have.
Or do you have Tunercat with which I'm not familiar.
Anyways I believe the stock shift points are about 5340 rpm at WOT.
With my new cam I've set the shift point to 5500 for now as I'm still feeling out the car and the roads haven't been WOT friendly yet. Also with the SC I don't want to blow my stock 100K+ bottom end.
I've put about 10,000 SC miles on so far with no real problems.
Maybe I'll reflash it to 5800 rpm in a month or so as you can always short shift by pulling your foot out of the pedal.
Numerically higher gears will make the car reach the set rpm shift point sooner.
I'm presuming you have LT-1 Edit which I have.
Or do you have Tunercat with which I'm not familiar.
Anyways I believe the stock shift points are about 5340 rpm at WOT.
With my new cam I've set the shift point to 5500 for now as I'm still feeling out the car and the roads haven't been WOT friendly yet. Also with the SC I don't want to blow my stock 100K+ bottom end.
I've put about 10,000 SC miles on so far with no real problems.
Maybe I'll reflash it to 5800 rpm in a month or so as you can always short shift by pulling your foot out of the pedal.
Registered User
Joined: Jul 2003
Posts: 700
From: Upstate New York
Re: 3.23-3.73
The shift points are set by the engine rpms and TP, not by changing the gear ratio.
Numerically higher gears will make the car reach the set rpm shift point sooner.
I'm presuming you have LT-1 Edit which I have.
Or do you have Tunercat with which I'm not familiar.
Anyways I believe the stock shift points are about 5340 rpm at WOT.
With my new cam I've set the shift point to 5500 for now as I'm still feeling out the car and the roads haven't been WOT friendly yet. Also with the SC I don't want to blow my stock 100K+ bottom end.
I've put about 10,000 SC miles on so far with no real problems.
Maybe I'll reflash it to 5800 rpm in a month or so as you can always short shift by pulling your foot out of the pedal.
Numerically higher gears will make the car reach the set rpm shift point sooner.
I'm presuming you have LT-1 Edit which I have.
Or do you have Tunercat with which I'm not familiar.
Anyways I believe the stock shift points are about 5340 rpm at WOT.
With my new cam I've set the shift point to 5500 for now as I'm still feeling out the car and the roads haven't been WOT friendly yet. Also with the SC I don't want to blow my stock 100K+ bottom end.
I've put about 10,000 SC miles on so far with no real problems.
Maybe I'll reflash it to 5800 rpm in a month or so as you can always short shift by pulling your foot out of the pedal.
Thread Starter
Registered User
Joined: Aug 2002
Posts: 2,325
From: BC
Re: 3.23-3.73
I am using Tunercat, though I would hope they both follow the same principals 
When I get home today I'll post some more details, from what I can recall it looked to me like the shift points require
A) RPM to be above a certain amount
and
B) X% amount of throttle to be applied @ a certain speed..
5340 seems way low for stock A4 shift points to me, I'm 98% sure mine (stock) shifts at around 57/5800 ish....
When I get home today I'll post some more details, from what I can recall it looked to me like the shift points require A) RPM to be above a certain amount
and
B) X% amount of throttle to be applied @ a certain speed..
5340 seems way low for stock A4 shift points to me, I'm 98% sure mine (stock) shifts at around 57/5800 ish....
Registered User
Joined: Jul 2003
Posts: 700
From: Upstate New York
Re: 3.23-3.73
my old stock program shows 5344 for 1-2 shift,
5440 for 2-3 shift and 5344 for 3-4 shift.
Ions update for my new cam heads and 58mm TB has 5550 for all the WOT shift points. He said it should shift
at 6000 rpm but I haven't revved it that high yet as the car spent a month at a shop for said mods plus a CPT trans, and I've only got it back last week.
Perhaps the cars shift higher than the inputted numbers, at least as far as OBDII LT-1 Edit goes.
5440 for 2-3 shift and 5344 for 3-4 shift.
Ions update for my new cam heads and 58mm TB has 5550 for all the WOT shift points. He said it should shift
at 6000 rpm but I haven't revved it that high yet as the car spent a month at a shop for said mods plus a CPT trans, and I've only got it back last week.
Perhaps the cars shift higher than the inputted numbers, at least as far as OBDII LT-1 Edit goes.
Thread Starter
Registered User
Joined: Aug 2002
Posts: 2,325
From: BC
Re: 3.23-3.73
Does LT1Edit show what that table name is?
I know there is a table in tunercat with shift points and RPM's in but its called:
Minimum shift @ WOT RPM vs MPH (or throttle?)
(Or something like that, again.. still at work. will check that too when i get home )
Which is why i think that table is the minimum RPM your engine has to be at to shift (And not the actual point the car shifts at)
There was also another table for called something like Normal shift points which is a table with Throttle % down the vertical axis and the shift point in the top axis, with MPH as the values in the table part.
I haven't put gears in the car yet, but its likely my next upgrade So.. just want to know whats involved on the comptuer side. Thanks for the help 2cub49, I'll post this thread a little alter tonight so we can compar the tunercat tables to what you have for lt1 edit!
I know there is a table in tunercat with shift points and RPM's in but its called:
Minimum shift @ WOT RPM vs MPH (or throttle?)
(Or something like that, again.. still at work. will check that too when i get home
)Which is why i think that table is the minimum RPM your engine has to be at to shift (And not the actual point the car shifts at)
There was also another table for called something like Normal shift points which is a table with Throttle % down the vertical axis and the shift point in the top axis, with MPH as the values in the table part.
I haven't put gears in the car yet, but its likely my next upgrade
So.. just want to know whats involved on the comptuer side. Thanks for the help 2cub49, I'll post this thread a little alter tonight so we can compar the tunercat tables to what you have for lt1 edit!
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