Should shift points vary by gear?

crashing_sux

crashing_sux

Blow Me?
I'm new to performance automatic tranny's but with manuals you shift based on where the motor makes power so it's around the same point every shift (at least on everything I've driven, it's right before redline).

My Syclone is exhibiting what seems to be strange behavior to me, the 1-2 shift happens right before 6k rpm, which feels perfect, but the 2-3 shift happens at 5k, too early causing the motor to drop down to 3k in third, falling right out of the powerband.

I just dumped $1200 into having my transmission internals put in a new case after breaking my previous case when a snapped propshaft slapped into the tranny so I'm dreading the thought of having to pay someone to get into it if that is what is required. The tranny shifts firmly and doesn't feel like it's slipping at all (it shouldn't, rebuild only a few thousand miles ago) so I'm thinking it might be some sort of configuration (governer?) problem but I really don't know much about these trannys.

CJSyclone recommended that I reset the TV cable which I did and it helped (before that the 2-3 shift was happening at 4.5k) but one strange thing I noticed is that right after resetting the cable the tranny felt a little better (firmer shifts, a little later which was good) they shifts got softer again at low throttle, like while cruising around town. I got out and reset it again and the shifts firmed up once more. This makes me think that the cable isn't holding it's adjustment properly. Does that sound reasonable? Is this common, and if so, is there an easy fix for it?
 
N

nates92ty

New member
ya man.....if ur trans is shifting at 6000, something isnt right.....my ty shifts at around 5000. u might want to ease up on the throttle a bit before u break something. I know of guys with even built set ups that doent even come close to 5400, never mind 6000. good luck :eek:
 
dgoodhue

dgoodhue

BuSTeD 4.3
Re: Should shift points vary by gear?

crashing_sux said:
I'm new to performance automatic tranny's but with manuals you shift based on where the motor makes power so it's around the same point every shift (at least on everything I've driven, it's right before redline).
Click to expand...

What mods does your motor have to support 6000RPM? Our Redline maybe higher, but the motor like to be shifted much earlier (infact the stock chip factorty RPM cutoff is 4800rpm) For a stock block/cam you want low shift points, actually any truck with stock internal is going to need to be a low reving motor to stay in one piece. My truck shift 4300 in 1-2 and 4500 2-3. I have been in quite a few trucks that 1-2 at 4000 rpm and 2-3 4300
 
crashing_sux

crashing_sux

Blow Me?
Wow, didn't realize everyone would think I had a stock truck when I specifically mentioned that at 3000rpm if was falling out of the powerband and that at 6000 it was right in it. Not it's not stock.

Nevermind what the specific shift point is, should the shift points change depending on what gear your are in? I would think it should be the same at wide open throttle every time.

Motor: Done By Rex Hutchinson Racing
>040 over JE pistons
<Eagle H Beam Rods
>Ported New vortec heads
<Comp Cam #422
>Ported intakes
<HPC Coated Headers
>T67 Turbo polished with HPC coated turbin housing
<Air/Air intercooler
>72lbrs with Accel DFI and also have 40lbrs with ecm and chip for 40's (for smog)
<ITS progate with electronic boost controller
much more.....

Trans: Done by High Tech Trans

>Full HD rebiuld with updated HD parts including 5 pinion planetary
<TCS 2,800 9/11 stall
>Derale pan
<B&M Racing cooler
 
dgoodhue

dgoodhue

BuSTeD 4.3
Shift points depend on the govenor, so you can have different 1-2 an d2-3 shift point, but you probably want to have them a little closer than what have right now.
 
C

Captain Morgan

Moderated User
Dave seems to have pretty much hit the nail on the head. Stock SyTy governors I believe are supposed to be rated at 4400 RPM shifts. Since our trannies are not electronically controlled, there isnt much that will effect the shift points unless the governor is actually changed or something is really wrong. The only other thing that will change shift points slightly is a higher stall converter.

My old trans and converter would shift solidly at 4375 in the 1-2 and 4375 in the 2-3. I havent datalogged my truck since going to a higher stall a few weeks ago, but it seems to be in the 4500 - 4600 range on both shifts.
 
Falco

Falco

Donating Member
Guys,

There are a lot of things, that can change shift poins even if you are not touching the tranny and it's working properly. First of all it's the converter. Second, where do you lock it. My Sy shifts around 5050 from 2nd to 3rd if my converter not locked and at around 4500 if it's locked.

Finally the shift points will change if you change the power output of your engine. As my engine became more powerfull in the past, shift points came higher and higher.

As far as the big difference between the 1st and 2nd shifts. There could be a difference, but 1000 RPM is something I've never seen (beside with locked converter as I mentioned above).

HTH,
 
crashing_sux

crashing_sux

Blow Me?
That's great, I had no idea the governer could be set to shift different gears at different rpms. I'll look into getting some different weights (or whatever they use to adjust those now).
 
SeattleSy#1255

SeattleSy#1255

Category 5 Conservative
a few things...his truck does this when the TC lockup switch is on and doesn't when its off...

also it would seem to me that 2800 stall is to low for a turbo that size and lastly, it would seem 40# injecters are to small.
 
crashing_sux

crashing_sux

Blow Me?
I'm running 72lb injectors, the 40's are just used to pass emissions. After unplugging the lockup today I realized that the tranny actually shifts at 5k on the 2-3 shift even without the lockup, I just didn't notice it because the motor wasn't falling so far out of the powerband. With the lockup the shift at 5k brought the motor down to 3k, and it just had no power. Without the lockup the shift still happens at 5k but the converter slips enough to keep the motor up over 4k where it still pulls hard.
 
crashing_sux

crashing_sux

Blow Me?
You might have just saved me some time here, I was about to start screwing with the governer but now I'll wait. I forgot to mention that I am waiting on Greddy to send me a new boost controller as the old one died on me. Without it I am way down on power, being limited to only 8lbs of boost.

I should have the controller back sometime this week hopefully, I'll just wait around until I get it back to do anything, being down 100hp or so might be the real cause of the early shifting.



Falco said:
Guys,


Finally the shift points will change if you change the power output of your engine. As my engine became more powerfull in the past, shift points came higher and higher.

HTH,
Click to expand...
 
TYRODD

TYRODD

My ass. Look at it.
crashing_sux said:
I'm running 72lb injectors, the 40's are just used to pass emissions. After unplugging the lockup today I realized that the tranny actually shifts at 5k on the 2-3 shift even without the lockup, I just didn't notice it because the motor wasn't falling so far out of the powerband. With the lockup the shift at 5k brought the motor down to 3k, and it just had no power. Without the lockup the shift still happens at 5k but the converter slips enough to keep the motor up over 4k where it still pulls hard.
Click to expand...

Geeze, what mods do you have to need those injectors :eek: ?
 
SeattleSy#1255

SeattleSy#1255

Category 5 Conservative
TYRODD said:
crashing_sux said:
I'm running 72lb injectors, the 40's are just used to pass emissions. After unplugging the lockup today I realized that the tranny actually shifts at 5k on the 2-3 shift even without the lockup, I just didn't notice it because the motor wasn't falling so far out of the powerband. With the lockup the shift at 5k brought the motor down to 3k, and it just had no power. Without the lockup the shift still happens at 5k but the converter slips enough to keep the motor up over 4k where it still pulls hard.
Click to expand...

Geeze, what mods do you have to need those injectors :eek: ?
Click to expand...

he has a full built motor with a t67....

sorry about the 40's, i didn't understand that now i do.
 
crashing_sux

crashing_sux

Blow Me?
That was a little confusing, I should have edited it out. When asked about my mods I just copied and pasted from the email CJSyclone sent me when I was talking to him about buying it.

I wonder if he'll change his name to CJTyphoon now that he owns a Ty?
 
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