shift lag
Banned
Joined: Mar 2003
Posts: 603
Likes: 0
From: L.I. NY
You are truly gifted at stating the obvious Watson. Not everyone has Edit to adjust their shift points. My HPP3 only allows me to shift at 6200 rpm and that's with +6 mph. The predator can give you rpm based shifts so it can go higher, but won't help my 98. Not to mention the fact that there's quite a bit of trial and error when adjusting it with Edit. It's not cut and dry, whereas manually shifting is. Can it be detrimental to the tranny, that's what I've heard. But so is beating the **** out of your car on the street/track. So either way it's gonna blow, sooner or later.
I have to manually upshift on the 2-3. If I leave it in drive, it will short shift at 5K and my car will fall on its face. This is because the HPP3 left some tuning in even after I had it dynotuned. We never caught the short shift on the dyno, and I haven't had it retuned yet.
Like mentioned above the line pressure may not keep up with the shifts unless the computer is doing it. An answer for this may be vacuum modulation. I'm not convinced that upshift kills these trannys, but I am convinced that manually downshifting will. One of my friends proved this with 2 transmissions. If I had a proper tune then I wouldn't manually upshift, but until then I don't really have a choice.
Like mentioned above the line pressure may not keep up with the shifts unless the computer is doing it. An answer for this may be vacuum modulation. I'm not convinced that upshift kills these trannys, but I am convinced that manually downshifting will. One of my friends proved this with 2 transmissions. If I had a proper tune then I wouldn't manually upshift, but until then I don't really have a choice.
TECH Fanatic
Joined: Mar 2002
Posts: 1,421
Likes: 0
From: Your Reality Check Bounced...
Ok...manually shifting a 4L60E does give you better RPM advantages over STOCK TUNING...a good tuner can up your line pressure and raise ur rev limiter and shift points so that your car will be way more consistant and let ur tranny live. By manually shifting you are causing the line pressure to build up way past what it ever should on the valves, Front Pump, etc. This will lead to failure...I've seen it on two of my friends car that liked to think they had 4 speed manuals and constinantly manually shifted their cars up and down when we'd be out cruising....the only manual shifting i'd do is bring it down a gear or two to bring the rpms up to about 4K then as soon as I punched it I'd put it back in OD before it got anywhere near it's shift points....w/a 440 NA motor and 550 on the dope....the thing lasted till 110,000 miles before the clutches started slipping in 3rd.....and I had to get a built one. only time you ever manually shift a 4l60E is if you have it built and have a manual valve body....on my supercharged, stroked, nossed 97 Z I put in a TH350....w/manual valve body.....now that thing snaps ur neck at each slap of my wrist to the next gear.
I hope this helps some.
I hope this helps some.
TECH Fanatic
Joined: Mar 2003
Posts: 1,384
Likes: 0
From: Jersey boy
Originally Posted by DeepBlueZ
no...the shifter is mechanically linked to a selector shaft that goes into the tranny...if you put the car in 1, it will not override 1st and go into second...the only thing you cant do is hold it in a higher gear than it should be in...(ex: starting off in 3rd, or cruising in 4th at like 20 mph)...you can start in second (00-02 cars i believe) by putting the shifter in 2....first gear, 3rd and 4th are completely locked out. good for snow.
TECH Fanatic
Joined: Oct 2003
Posts: 1,514
Likes: 0
From: Long Island, NY
Originally Posted by BigPlanTransAm
thats not entirely true, sometimes when im turning at ~25-30mph and i want to feel a torque form the top of first i pull it into first as i come out of the turn and it will go into first and shift right to second while the selector is still in first . the first time i didnt realise how fast it revved and it was an accident but now i dont even worry about it.
2.) dont downshift to first with the car going 30 mph...
Last edited by DeepBlueZ; Apr 6, 2004 at 05:31 PM.
TECH Fanatic
Joined: Oct 2003
Posts: 1,514
Likes: 0
From: Long Island, NY
Originally Posted by JoSeY
Ok...manually shifting a 4L60E does give you better RPM advantages over STOCK TUNING...a good tuner can up your line pressure and raise ur rev limiter and shift points so that your car will be way more consistant and let ur tranny live. By manually shifting you are causing the line pressure to build up way past what it ever should on the valves, Front Pump, etc. This will lead to failure...I've seen it on two of my friends car that liked to think they had 4 speed manuals and constinantly manually shifted their cars up and down when we'd be out cruising....the only manual shifting i'd do is bring it down a gear or two to bring the rpms up to about 4K then as soon as I punched it I'd put it back in OD before it got anywhere near it's shift points....w/a 440 NA motor and 550 on the dope....the thing lasted till 110,000 miles before the clutches started slipping in 3rd.....and I had to get a built one. only time you ever manually shift a 4l60E is if you have it built and have a manual valve body....on my supercharged, stroked, nossed 97 Z I put in a TH350....w/manual valve body.....now that thing snaps ur neck at each slap of my wrist to the next gear.
I hope this helps some.
I hope this helps some.
yea i think i said i understand why manually downshifting the car might be bad for it...if your friends drove like they had a manual valvebody all the time, i understand it failing...what im saying is i find it very hard to believe that clicking 1,2,D at the track is going to shorten the life of the trans....theres a difference between driving the car like an M6 and holding a gear for a few hundred extra revs at the track once in awhile. The computer is programmed with a predetermined maximum amount of line pressure it will allow in the tranny REGARDLESS of where the shifter is located...with stock tuning, i find it hard to believe GM would set it high enough to wear out valves and seals....once someone has fiddled with the tranny fucntions, thats another story...
Well if some of you guys agree that it is better to manually shift your car when it was stock, then explain this? I have seen a lot of stock LS1 dynos and most of them stop making power some where around 5800-6000 so why shift it above that if your not making anymore power? I can understand on a modded LS1 but not a stock one. And i still think we could never shift the car faster then the PCM can shift it. Just my .02
TECH Addict
Joined: Sep 2003
Posts: 2,065
Likes: 0
From: Atlanta, GA
shift extension, the stock verter sucks butt on SE. Too small of a verter would also probably require more rpm's beyond stock to keep the shift extension optimized to run a decent time.
of course buying the right verter for your setup and tuning it will yield better results im sure.
of course buying the right verter for your setup and tuning it will yield better results im sure.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo TECH Fanatic
Joined: Oct 2003
Posts: 1,514
Likes: 0
From: Long Island, NY
Originally Posted by PunkNPonys
Well if some of you guys agree that it is better to manually shift your car when it was stock, then explain this? I have seen a lot of stock LS1 dynos and most of them stop making power some where around 5800-6000 so why shift it above that if your not making anymore power? I can understand on a modded LS1 but not a stock one. And i still think we could never shift the car faster then the PCM can shift it. Just my .02
2.) ill say it again, NOBODY said anything about shifting "faster" than a computer...you're thinking in terms of an M6 where shifting is actually a process...when we click the selector into the next gear, the computer is still going through the shift process the same speed (as in the shift takes the same amount of time) as it would if the computer was controlling gear selection itself....we are simply NOT ALLOWING the computer to shift until a higher RPM so the next gear will engage IN the power band....
see the difference???
Yeah your right about the shift extensions i wasnt even thinking about that. I am glad i dont have to worry about that now with my stall......
And about the "faster" shifts i still dont know which is better but i still think the PCM shifts the Tranny just fine but thats just in my situation.
And about the "faster" shifts i still dont know which is better but i still think the PCM shifts the Tranny just fine but thats just in my situation. TECH Fanatic
Joined: Oct 2003
Posts: 1,514
Likes: 0
From: Long Island, NY
Originally Posted by PunkNPonys
Yeah your right about the shift extensions i wasnt even thinking about that. I am glad i dont have to worry about that now with my stall...... And about the "faster" shifts i still dont know which is better but i still think the PCM shifts the Tranny just fine but thats just in my situation.
And about the "faster" shifts i still dont know which is better but i still think the PCM shifts the Tranny just fine but thats just in my situation.with a high stall i completely agree with you....i let it shift itself now...i was simply saying i was able to eek out a little more ET when i had the stock converter.
Banned
Joined: Mar 2003
Posts: 603
Likes: 0
From: L.I. NY
And who taught you to do that Mr Deep Blue Z? That night on DPA when you lined up against a silver 98 Z? LOL
The shifting faster than the computer thing has been sarcastically brought up by people when I've posted about manually shifting the car in other posts. Seems some folks believe that's what I was saying when telling them to shift the car manually. Anyways, if you don't have a HPP3, Predator or Ls1Edit, then shifting the car manually will help you go faster. That was my first mod, if you wanna call it that, and it was worth .19 sec and 1.9 mph. And winding it out and finishing the quarter in 2nd was worth another 1.5 mph. When shifting any car it's recommended that you shift approx. 10% higher in RPM then where your HP is at. IE: 5500 rpm HP peak, shift at 6000 or so. From my experience with my 98, which has a more peaky HP cam than say an 01-02, the car pulled all the way to the 6600 rpm rev limit w/o falling on it's face. So w/ 2.73s I was able to finish the 1/4 in 2nd at 108 mph. 108 is pretty damn good for a 98 w/ a lid, filter, catback and 2.73 gears weighing 3650+ with driver.
The shifting faster than the computer thing has been sarcastically brought up by people when I've posted about manually shifting the car in other posts. Seems some folks believe that's what I was saying when telling them to shift the car manually. Anyways, if you don't have a HPP3, Predator or Ls1Edit, then shifting the car manually will help you go faster. That was my first mod, if you wanna call it that, and it was worth .19 sec and 1.9 mph. And winding it out and finishing the quarter in 2nd was worth another 1.5 mph. When shifting any car it's recommended that you shift approx. 10% higher in RPM then where your HP is at. IE: 5500 rpm HP peak, shift at 6000 or so. From my experience with my 98, which has a more peaky HP cam than say an 01-02, the car pulled all the way to the 6600 rpm rev limit w/o falling on it's face. So w/ 2.73s I was able to finish the 1/4 in 2nd at 108 mph. 108 is pretty damn good for a 98 w/ a lid, filter, catback and 2.73 gears weighing 3650+ with driver.
TECH Fanatic
Joined: Oct 2003
Posts: 1,514
Likes: 0
From: Long Island, NY
Originally Posted by SilverSurfer
And who taught you to do that Mr Deep Blue Z? That night on DPA when you lined up against a silver 98 Z? LOL
The shifting faster than the computer thing has been sarcastically brought up by people when I've posted about manually shifting the car in other posts. Seems some folks believe that's what I was saying when telling them to shift the car manually. Anyways, if you don't have a HPP3, Predator or Ls1Edit, then shifting the car manually will help you go faster. That was my first mod, if you wanna call it that, and it was worth .19 sec and 1.9 mph. And winding it out and finishing the quarter in 2nd was worth another 1.5 mph. When shifting any car it's recommended that you shift approx. 10% higher in RPM then where your HP is at. IE: 5500 rpm HP peak, shift at 6000 or so. From my experience with my 98, which has a more peaky HP cam than say an 01-02, the car pulled all the way to the 6600 rpm rev limit w/o falling on it's face. So w/ 2.73s I was able to finish the 1/4 in 2nd at 108 mph. 108 is pretty damn good for a 98 w/ a lid, filter, catback and 2.73 gears weighing 3650+ with driver.
The shifting faster than the computer thing has been sarcastically brought up by people when I've posted about manually shifting the car in other posts. Seems some folks believe that's what I was saying when telling them to shift the car manually. Anyways, if you don't have a HPP3, Predator or Ls1Edit, then shifting the car manually will help you go faster. That was my first mod, if you wanna call it that, and it was worth .19 sec and 1.9 mph. And winding it out and finishing the quarter in 2nd was worth another 1.5 mph. When shifting any car it's recommended that you shift approx. 10% higher in RPM then where your HP is at. IE: 5500 rpm HP peak, shift at 6000 or so. From my experience with my 98, which has a more peaky HP cam than say an 01-02, the car pulled all the way to the 6600 rpm rev limit w/o falling on it's face. So w/ 2.73s I was able to finish the 1/4 in 2nd at 108 mph. 108 is pretty damn good for a 98 w/ a lid, filter, catback and 2.73 gears weighing 3650+ with driver.
Thread Starter
On The Tree
Joined: Dec 2003
Posts: 104
Likes: 0
From: McAllen, TX
Well, I picked up a ported throttle body and stock MAF yesterday. The car feels alot smoother but I noticed that it doesn't quite shift as hard anymore. I also did a couple of ram air mods and did the throttle body bypass while I was already messing around. I was going to test it out at the track but it started raining a little and the track closed. I'm going to try the start in 2 and manually shift to 3 trick and see how that goes. Hopefully I'll hit better than a damn 13.5, if not i'm selling the car. LOL,
One more thing, today is my 18th birthday!!
One more thing, today is my 18th birthday!!
