BooC5

I have an 01 C5 Corvette A4 with stock 3.15 gears. I want to know if something mild like a Yank ST3000 will give me a good gain at track, retaing tightness while gettin groceries, and NOT destroy the tires off the line?? I am also interested to know how large the gains are in ET between say and ST3000 and an SS3200. I am running a set of ZO6 wheels 295/35/18s on the rear Goodyear Eagle F1s. I have asked on the Corvette Forum, but I figure there will be more F-body owners here and that more F-body owners use their cars as daily drivers/track cars. I am very interested in what gains were made from different converters! I am trying to make sure I spend my $$ on the right mods! Thanks for any input!

MattZ28

iTrader: (4)

street tires = spin spin spin

BooC5

That is what I keep hearing. If this is true with ALL stalls? I might as well get an SS3600 and put in a 3.42 gear.. and get some drag radials.

MattZ28

iTrader: (4)

More or less, yeah. More torque multiplication will just roast the tires.

EDS01SS

iTrader: (30)

Yup that is your best bet.

Shinsetsu

iTrader: (2)

smoke

s346k

iTrader: (4)

tiresmoke

BooC5

Well how is performance with DOT drag radials? What I would really like to use is some high performance street tires that are very good for road racing or even autoX that I can get about 6K+ miles or so out of em. Would some of these tires handle the torque pretty well? The ST3000 stall has an STR of 1.95 I think.

jimmyblue

iTrader: (11)

Floored = smoke but you don't -have- to drive that way.
You have to get the feel for it and then the car can be
-more- controllable, pedal proportional torque (especially
once you have the shiftpoints dialed in). Stock F-bodies
have all-or-nothing shift profiles, you're stuck at low RPM
and hence low torque until you are up over 90% TPS and
then it kicks down (hard). And the low stall, low STR makes
for low multiplication on sub-peak torque off the line.

My TCI SF3000 would spin all of 1st, through the shift and
well up into 2nd (until the multiplication faded w/ RPM).
But that's matted, and I learned to pedal it up short of
spin after a while (mostly ). 3.15s will be somewhat
more forgiving than 3.42s but it was a handful even on
3.23s. Bigger wheels also cut the shear force on the
rubber (constant torque, more radius).

The lower the STR the more elastic ("loose") the coupling,
but this can be good depending on what you like; it will
let you cruise at light pedal, lower but need more pedal,
up top to get the same "thrust". I have a 3500/2.0 now
(from 3000/2.2) and I can cruise level at 30MPH, 1500RPM
same as before; up hills maybe 200RPM higher (2200 vs
2000). The coupling is softer but the new combo is even
more pedal-controllable, I spin less but wide open it's a
better match to the powerband; the 3000 kind of pulled
hard (initial STR), then laid down a little, then came back
on with the motor torque curve. The 3500 is flatter, more
constant-torque. You want the multiplication and its fade
profile to complement the torque curve of the motor; too
much STR just wastes rubber and fades early, too little
and it feels sloppier to drive. You can see some curves on
Yank's site; some converters make a huge low torque peak
(imagine hooking that up), fall down and come back up.
Some produce a moderate low-wnd peak but never fall
below motor/locked peak. The combination varies with
the motor torque curve, built ones benefit more from a
higher stall, higher STR because the high end is up more
relative to the low end. Tires will only hold so much rear
wheel torque. A very uneven torque w/ pedal, RPM is not
friendly to tires.

1BAD98TA

iTrader: (11)

I can see almost exactly what JimmyBlue is saying.. its amazing how he can explain things in depth to let even a novice know what he is talking about.. basically I want my stall to quit doing its "work" right about the time the engine can take over and keep the "pull" going on its own.. just a nice transistion... between engine and stall.. but, I thought that the lower numerically STR rating would give you a more solid feel.. I thought the higher the number for the STR the "looser" it felt.. the higher the number the better chances of getting whip lash, but also the better chances that stop and go traffic wont be all that much fun.. Did I read his post wrong or am I just wrong about STR??

jimmyblue

iTrader: (11)

There's a coupling slope that gets steeper with more STR.
So for the same stall speed, a lower STR will feel looser
when you're getting into it, but it will creep and cruise at
lower RPM than a higher STR. On the flip side when the
high STR converter comes on, it comes on harder and
the low-STR one is slipping more (but still multiplying
some).

I think the "tight/loose" depends on where in the RPM
and throttle range you're talking. For me to cruise at
the same speed, same unlocked RPM on a 500RPM
higher, 0.2 STR lower converter kind of shows how
the low-RPM "soft coupling" extends down more w/
lower STR (though mid-pedal is indeed "looser").

This is a good picture from Yank's site:

http://www.converter.cc/techtalk/tech2.htm

Scotty-Z

iTrader: (5)

Yeah, Jimmy there explained it well. You have to learn to really feather the throttle and know just how hard you can push the car before it starts to break loose. Really takes some getting used to and you'll have plenty of smoke while you experiment.

SmokingWS6

iTrader: (1)

exactly. You can learn to pedal it. Normally just tire smoke. I'd blow through 1st gear, hit 2nd and spin half way through it. BTW this was before my heads/cam

With my Mickey Thompson DR's I can flash it from a stop on fresh concreet and it'll spin to about 15, 20 mph(but your moving foward quickly while spinning) then hook very hard and run out first and hit second with no 2nd gear scratch at all. If I lower my tire pressure and do a burnout it'll practically dead hook.

BubaGumpShrimp

iTrader: (1)

i went from a 3k stall 2.0 str to a 3,800 stall and a 1.7 str and the tires spin just as bad but its easier to feather the pedal

BooC5

So basicly. Even on the street w/ street tires there can be a gain in performance if I learn to feather the pedal properly and not just mash it. Is the throttle response with a stall smooth and linear like stock? I know on hills etc it will roll, and if hit the gas hard it will unleash fury upon street tires begging for mercy. I am just wondering if a stall makes attacking curvy roads or auto crossing much more difficult. For example: if I am going around a corner and want to accelerate just a little bit while in the corner will it accelerate smoothly and gradually like stock? Does a stalled car drive like stock other than rolling on hills and hitting hard when you mash it? Please excuse my ignorance guys. I really need to find someone who has a stall so I can drive their car and see how it is. Thanks for all the input so far!!

12secSS

iTrader: (30)

I autocross my stalled 2001 Camaro SS. I typically am with a second or two of the top three finishers in ESP. It will take some getting used to, but with more seat time you'll know how to handle it.