Compushift CS3
Thread Starter
TECH Fanatic
Joined: Sep 2003
Posts: 1,058
Likes: 1
Compushift CS3 Now I've done it. Swapped to a vaginamatic.
Just converted to a 4L65E and am setting up the trans controller. The engine will be shifted at 7,500rpm and am thinking I should set the shift point at 6,500 for the trans controller to
give the trans a moment to shift. Any idea how long it takes a 4L65E to shift? I guess this is related to pressure settings too.
Comments welcome.
Just converted to a 4L65E and am setting up the trans controller. The engine will be shifted at 7,500rpm and am thinking I should set the shift point at 6,500 for the trans controller to
give the trans a moment to shift. Any idea how long it takes a 4L65E to shift? I guess this is related to pressure settings too.
Comments welcome.
TECH Junkie
Joined: Dec 2012
Posts: 3,605
Likes: 1,316
From: Iowa
no mention of the setup.
what vehichle. what weight. how much power. what rear gear. what's done to the trans. etc etc.
Lots of variables...nobody can just say "yep give it a 1000 rpm of lead time and it'll be fine" without knowing any of the details
P.S. if you're shifting a 60e at 7500 rpm and you don't have some decent work done to it internally, you're going to have trouble in the long term
what vehichle. what weight. how much power. what rear gear. what's done to the trans. etc etc.
Lots of variables...nobody can just say "yep give it a 1000 rpm of lead time and it'll be fine" without knowing any of the details
P.S. if you're shifting a 60e at 7500 rpm and you don't have some decent work done to it internally, you're going to have trouble in the long term
Thread Starter
TECH Fanatic
Joined: Sep 2003
Posts: 1,058
Likes: 1
no mention of the setup.
what vehichle. what weight. how much power. what rear gear. what's done to the trans. etc etc.
Lots of variables...nobody can just say "yep give it a 1000 rpm of lead time and it'll be fine" without knowing any of the details
P.S. if you're shifting a 60e at 7500 rpm and you don't have some decent work done to it internally, you're going to have trouble in the long term
what vehichle. what weight. how much power. what rear gear. what's done to the trans. etc etc.
Lots of variables...nobody can just say "yep give it a 1000 rpm of lead time and it'll be fine" without knowing any of the details
P.S. if you're shifting a 60e at 7500 rpm and you don't have some decent work done to it internally, you're going to have trouble in the long term
TECH Junkie
Joined: Dec 2012
Posts: 3,605
Likes: 1,316
From: Iowa
I never believe the sig.
Some people haven't updated theirs in years...and sometimes when you check threads that say "check sig"...but the thread is 6 years old and the sig has changed...it doesn't help anybody that is trying to view that old thread for good info.
So...your setup is
"02 EB Z06 416cid LS3, 648rwhp/524rwtq,Callies Crank/Rods,
CP Gas Ported Pistons, Holley Hi-Ram LS7/NW Boosted 102mm, Comp Cams Solid Roller Cam, Isky EZ Roll Lifters, T&D Shaft Mount 1.7s, Mast 265cc LS7, RPS Carbon Clutch, RaceTronix, EFI Live COS5 w/LC2s, NHRA Cert'd Cage. "
A. I would talk to rpm and see what they recommend
B. I would sure as hell hope you don't have to program in 1000 rpm of lead time for the shift. I would hope .2 sec or less from commanded shift until completed shift. So...if you know how quickly your car accelerates through the rev range you can estimate.
What I would recommend is starting with a 6500 rpm shift point and do a WOT pull. Log it. If it shifts at 6700...you know how long it takes AT THAT POINT IN THE REV RANGE. Then do a log at 6600 commanded shift. So on and so forth. Work up until you find the proper speed/rpm that works for you.
If you want it to actually shift at 7500...I would think that 7250 would be early enough to command a shift...but I can't say that with confidence.
Once you figure it out, please report back.
P.S. what are you using for engine management
Some people haven't updated theirs in years...and sometimes when you check threads that say "check sig"...but the thread is 6 years old and the sig has changed...it doesn't help anybody that is trying to view that old thread for good info.
So...your setup is
"02 EB Z06 416cid LS3, 648rwhp/524rwtq,Callies Crank/Rods,
CP Gas Ported Pistons, Holley Hi-Ram LS7/NW Boosted 102mm, Comp Cams Solid Roller Cam, Isky EZ Roll Lifters, T&D Shaft Mount 1.7s, Mast 265cc LS7, RPS Carbon Clutch, RaceTronix, EFI Live COS5 w/LC2s, NHRA Cert'd Cage. "
A. I would talk to rpm and see what they recommend
B. I would sure as hell hope you don't have to program in 1000 rpm of lead time for the shift. I would hope .2 sec or less from commanded shift until completed shift. So...if you know how quickly your car accelerates through the rev range you can estimate.
What I would recommend is starting with a 6500 rpm shift point and do a WOT pull. Log it. If it shifts at 6700...you know how long it takes AT THAT POINT IN THE REV RANGE. Then do a log at 6600 commanded shift. So on and so forth. Work up until you find the proper speed/rpm that works for you.
If you want it to actually shift at 7500...I would think that 7250 would be early enough to command a shift...but I can't say that with confidence.
Once you figure it out, please report back.
P.S. what are you using for engine management
Thread Starter
TECH Fanatic
Joined: Sep 2003
Posts: 1,058
Likes: 1
Until this point I have used EFI LIVE and a pair of wide bands, but my tuner (Rick at Synergy Motorsports, Livermore, CA) did such an outstanding job using a custom operating system by HP TUNERS that I also
ordered a copy of it so we could coordinate tuning the car.
We plan to set the trans controller to 6,500rpm and see what happens, then I'll play with pressures a little.
ordered a copy of it so we could coordinate tuning the car.
We plan to set the trans controller to 6,500rpm and see what happens, then I'll play with pressures a little.
