2400 Stall, Shift Kit Removal?

[RatedZ]

I have a 2400 rpm stall in my car, but I'm thinking about removing the shift kit because at low speeds around town it shifts really hard...to the point it feels like the front wheels are coming up! But, I do get a nice chirp of the rear tires (not that I care).

Am I putting a lot of wear on the transmission/rear by having a shift kit installed? Would it be more beneficial to go with a PCM tune for a slightly snappier shift over a shift kit?

I just wanna extend the life of these parts....

[SilverZConvertible]

I think with a shift kit you're putting less wear on the tranny as it prevents two gears from being engaged at the same time. GM does this (and everyone else) to smooth out the transition between shifts. Shift kits don't do this (or they overlap the gears less) thus making the car shift harder. When the tranny is stock and the gears are smoothly overlapping more heat is generated and this reduces the life on the tranny.

Now for the rear, yeah I'm guessing that its taking more abuse than a stock rear would so I don't know where that leaves you in the decision process.

My driveline mechanic told me when he did my kit that he can back off the firmness of the shifts or increase the firmness. My car shifts pretty hard but I like it. I just give her a little more juice around the corner and get that back end to slide out a little that seems to smooth things out

I only know this infor third hand I'm not mechanic and certainly no tranny specialist

Also is your pcm tune stock? If not maybe the last owner increased the shift firmness and with that and the shift kit can make things very uncomfortable. Might be worth looking into the tune thats in your cars computer.

[RatedZ]

Originally Posted by SilverZConvertible

I think with a shift kit you're putting less wear on the tranny as it prevents two gears from being engaged at the same time. GM does this (and everyone else) to smooth out the transition between shifts. Shift kits don't do this (or they overlap the gears less) thus making the car shift harder. When the tranny is stock and the gears are smoothly overlapping more heat is generated and this reduces the life on the tranny.

Now for the rear, yeah I'm guessing that its taking more abuse than a stock rear would so I don't know where that leaves you in the decision process.

My driveline mechanic told me when he did my kit that he can back off the firmness of the shifts or increase the firmness. My car shifts pretty hard but I like it. I just give her a little more juice around the corner and get that back end to slide out a little that seems to smooth things out

I only know this infor third hand I'm not mechanic and certainly no tranny specialist

Also is your pcm tune stock? If not maybe the last owner increased the shift firmness and with that and the shift kit can make things very uncomfortable. Might be worth looking into the tune thats in your cars computer.

My pcm was tuned by www.pcmforless.com. I didn't have Bryan firm up the shifts, as I had a shift kit.

Thanks for the post!

[titter]

Yes shift kits are a lot better on the tranny then boosting the line pressure the "hypertech" way. I just had a stage-2 transgo installed, and i am going to actually boost the pressure inside the tranny manually when i do my fluid change soon.

I still think your stall is way to small ... way way to small, almost to the point its no different then stock. I have a vig 3200, and actually want to goto a 3400 fuddle. stalls are meant to lift rpm to get a better torque multiplication for an automatic ... having such a small stall you would hardly notice the difference from a stock stall, and besides the fact i can foot brake launches and flash higher there is no effect on every day driving on my car.

[RatedZ]

Originally Posted by titter

Yes shift kits are a lot better on the tranny then boosting the line pressure the "hypertech" way. I just had a stage-2 transgo installed, and i am going to actually boost the pressure inside the tranny manually when i do my fluid change soon.

I still think your stall is way to small ... way way to small, almost to the point its no different then stock. I have a vig 3200, and actually want to goto a 3400 fuddle. stalls are meant to lift rpm to get a better torque multiplication for an automatic ... having such a small stall you would hardly notice the difference from a stock stall, and besides the fact i can foot brake launches and flash higher there is no effect on every day driving on my car.

I tend to disagree with you about the stall being too small, and here's why, but before I go into a detailed explanation, I tried a "powerbrake" this morning and the brakes wouldn't even hold the car in place. The brakes are new, and they stop straight and true; not that this has anything to do with it.

Here's the deal with my car. I could be travelling at at 55-60 mph, stomp the gas, and the trans kicks down into 2nd gear. It still has the stock 3.23s. The moment it kicks down into 2nd gear the car squats, the revs come up, and then it shifts hard back into 3rd, and hold on tight, cuz you're in for a ride. The problem is, that when it hits back into 3rd, the car heads straight towards the right shoulder of the road, even at such a "high" speed. With little "surprises" like that going on, I'm scared to death to mash the throttle on that thing. I can't imagine how much more horrible it would be with a higher stall. For the record, I also have a shift kit.

I mean, look at my mods. The car is not that fast. What would you say, about maybe 13.50s @ 101-103 mph at best?

Now, I recently brought the car into the shop because as I rounded a right corner the wheel would squeal like it were brakes. They informed me that there was a C-Clip in the right rear that was wearing out and it would run about $200 to replace. Also, when briskly accelerating from a stop, I notice that the back end feels like it's "wallowing" back and forth, but it is NOT wheel spin. There is total traction, but the back end just feels like it's moving side to side ever so slightly. Very strange.

Now, maybe this is my issue, but I'm not sure, but it's just a downright scary car to drive.....

[titter]

haha trust me, a 3200 isnt to high! i have seen daily driven stock ls1's with 4000-4400 stalls. right now anything from about 20-30 on my bad street tires really gets me spinning. i have no mods besides a flowmaster and my stall ... soon i will go with some bolt ons and see if i get a nice hefty 12 second slip, on a good sticky tire.

sounds like something is out of whack right now also ... it shouldnt be kicking you to the right lol. hell i get on my car quite a bit, and it stays where i tell it too, unless its raining then it has its own mind! im not a suspension/rear end guru ... but could be a bad posi if your hitting it and only one wheel is out spinning the other, it would cause for an interesting push, but dont quote me on that. i know i have seen limited slip rear ends make noises only in turns when the posi is going bad .. could be something like that here.

[Randy L]

I also agree that you should look into the rear end for components needing replacement. Heck, if it's gonna cost $200 per ring to replace, why not invest in a whole "NEW" rear end?

If the rear end is good but you're still mistracking on hard acceleration, I believe this is an indication you need suspension work.

Now here's a little technical question for the experts here. A high stall converter is used to get the RPM's up higher for better torque on take off. Now experts say it's the torque that allows a car to launch hard and accelerate fast. HOWEVER...isn't the LT1's torque pretty much at peak in the low 2K RPM range and remains relatively flat until around 5300RPM where it begins to fall off? With this in mind, I wonder if a fairly stock LT1 would benefit from a very high stall TC (say 3500RPM+). Maybe a stall as low as mid to upper 2K range is all that's needed and then the shift kit will take over and keep the RPM's up high between shifts so the engine doesn't bog down when it shifts up.

I'm sure the torque curve is much different on a heavily modded engine which then would benefit from a HS TC?

[RatedZ]

Originally Posted by titter

haha trust me, a 3200 isnt to high! i have seen daily driven stock ls1's with 4000-4400 stalls. right now anything from about 20-30 on my bad street tires really gets me spinning. i have no mods besides a flowmaster and my stall ... soon i will go with some bolt ons and see if i get a nice hefty 12 second slip, on a good sticky tire.

sounds like something is out of whack right now also ... it shouldnt be kicking you to the right lol. hell i get on my car quite a bit, and it stays where i tell it too, unless its raining then it has its own mind! im not a suspension/rear end guru ... but could be a bad posi if your hitting it and only one wheel is out spinning the other, it would cause for an interesting push, but dont quote me on that. i know i have seen limited slip rear ends make noises only in turns when the posi is going bad .. could be something like that here.

I thought about maybe it could be a bad posi unit, and you may be very right. I only get kicked to the right when the car is at speed and downshifts into 2nd. If I'm going around 70-75 mph it only downshifts into 3rd and I don't experience any adverse reactions....

[titter]

the stall causes torque multiplication to the rear wheels, so at lower speeds it would be a lot worse then at higer speeds. i really think its a bad posi, but like i said let fanta or someone else on here chime in. they will know a lot more then me.

and randy yes you dont want to go to high in the lt1, i wouldnt suggest higher then a 3600 personally. like you said we make low end tq, but you want to hit the peak tq number not really stay in the tq curve longer since your stalled car also will upshift and not allow a huge drop in rpms. when they dyno'd my car it was pulled from 3,500rpm and my tq peak was at 4,000rpm. my 3200 stall flashes to 3200-3300 almost dead on, and i can foot brake it to around 2300 on bald street tires, with a bigger tire or better compound i will get that up as well.

basically when my car upshifts from 1 to 2, for example my rpms only drops back down to 4,000 rpm which keeps me right at my peak tq, but not only at my peak tq but also at a higher hp level. the tq curve does dive down around 5,000 rpm, but! big but! once you are rolling tq isnt needed as much as hp is ... so since my peak hp was at 5,200 rpm, and the stall is keeping my rpms higher after a shift im not losing all my hp once i get past the 330' and make my shift :] stalls mixed with a good shift kit should keep you in your power band a lot longer, reducing e/ts. going to high can be bad, staying to low and you might not get the same numbers you could with going higher.

[RatedZ]

If the rear in my car is wearing out, how much would it cost to replace all of the parts? I'm not interested in upgrading to a 12 bolt or anything like that. I don't race the car. I'd be perfectly happy with sticking with the stock rear with different internals.

What are all of the parts that I would need? I would only want to upgrade to 3.42s, as I would like to keep some amount of decent fuel mileage.

[titter]

not that much, you can pick up 10 bolts everywhere from people who upgraded to a 12 bolt or 9in. i would say 250-300 at most on refresh a 10 bolt, or 100 or so for a good used one. all depends on what you do :] i know soon enough ill be going with a 12 bolt, and will probably sell my 10 bolt for 35-40 + shipping lol.

[RatedZ]

Originally Posted by titter

not that much, you can pick up 10 bolts everywhere from people who upgraded to a 12 bolt or 9in. i would say 250-300 at most on refresh a 10 bolt, or 100 or so for a good used one. all depends on what you do :] i know soon enough ill be going with a 12 bolt, and will probably sell my 10 bolt for 35-40 + shipping lol.

Awesome, but how much do the internals of it go for? I wanna keep the original rear casing in my car since it's a B4C model. You know, the "originality" thing....engine, transmission, and rear.

[titter]

lol the b4c rear is the same as any other gu5 rear end from that year :] call around to some shops and tell them you need your 10 bolt rear refreshed ... they should give you some prices

[RatedZ]

Originally Posted by titter

lol the b4c rear is the same as any other gu5 rear end from that year :] call around to some shops and tell them you need your 10 bolt rear refreshed ... they should give you some prices

I know it is. I just want to keep the casing so it's #s matching.