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gears affect stall choice?

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Old 07-11-2012, 11:32 PM
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Default gears affect stall choice?

I am in the market for a converter, and i understand having different ratio gears changes the behavior of the stall.

With that in mind, do guys take the gears into consideration when buying a converter(as in choosing a different stall speed)? or do you just accept that some things will be different than expected, i.e. footbrake rpm and stuff like that.

i guess what i'm trying to say is would you recommend the exact same stall for two different cars, all things being equal except different gears?
Old 07-12-2012, 07:12 AM
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It really all comes down to personal preference. Basically gears will affect how tight a converter feels while not in lockup. STR also plays a part. A basic breakdown for you:

STR (stall-torque-ratio): Lower is usually tighter, higher is usually looser. Lower doesn't hit the tires quite as hard initially and will multiply longer, higher multiplies torque more initially hitting the tires harder and less later on.
Stall speed: Lower stall speed is usually tighter because the car doesn't have to rev that high to meet the stall speed compared to higher stall. Higher stall speed is usually looser because of the opposite.
Gears: Taller gears (numerically lower) will be looser than shorter gears (numerically higher)

How does it all work together? It's tricky. I'll use my case as an example. I have 2.73 gears in my car and wanted something with a lower STR so that it wouldn't be so hard on the tires. What I found though is that lower STR with 2.73 gears isn't that good, it actually makes the car feel looser than going with a higher STR with 2.73's because the higher STR helps get the car moving easier.

Fore more in-depth, yet simple enough to read, description check out this thread: http://www.ls1gto.com/forums/showthread.php?t=349786
It is a VERY good writeup
Old 07-13-2012, 09:25 AM
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well i have 3.73s, i'd probably like a slightly lower STR, but the cam i am running is a Vengeance VRX5. So i'm gathering information about what stall and STR i should run, also considering the gears i have. My last f-body was stalled (1st a 3400 stall 2.1 STR then a vig 4000) and i admit the high STR is fun to drive. But i think with this car i may need something a little more tailored for mostly street/some strip.
Old 07-13-2012, 11:49 AM
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Check out FTI SRLS0086. It is a 3600 stall speed on a 1.78 - 1.86 STR. A lot of GTO guys run that converter in DD setups with cams that size and love it.
Old 07-14-2012, 10:07 AM
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Ultimately it's a matter of the difference between the crank rotation and rear wheel rotation. A converter is going to feel "looser" with higher gears because higher engine rpm will be required to get the car moving. Higher stall speed and lower the STR will create greater looseness. It's all a matter of what you can tolerate.

I've run a 3600/2.5 and a 3000/2.2 with 3.42 gears and they've felt about the same. I like a tighter feel, so running those converters with 2.73's would be too loose for me.
Old 07-14-2012, 09:20 PM
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Eh, gears don't effect too much. I had the 3.73's installed at the same time as my stall just because it seemed like the right thing to do.



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