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just called the local parts house and heres what they pulled up

'95 caprice tc stalls @ 1800
'95 s10 (4.3) stalls @ 1800
'95 corvette stalls @ 1400

$149. for the s10 TC
 

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what year s10?
Post #13 in THIS thread....SMH

* DGHG = stock '94+ Impala converter
* DBCF = '86 'vette converter
* DBLF = '95+ L35 S10 truck converter

To get the high stall converter in an updated form with the latest design, order a similar K-140 high stall converter from a 1995+ 4.3L (RPO L35) S10 Truck V6 application (p/n 24202310).


jeeze...
-ALF out...
 

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Does a stall converter make the passing gear feel stronger? Or is it just an off the line thing?

I got a 94 caprice. 3.08 rear.
 

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Does a stall converter make the passing gear feel stronger? Or is it just an off the line thing?

I got a 94 caprice. 3.08 rear.
No, especially for a stock engine, it's not a very noticeable difference when it downshifts (into "passing gear"). It's more effective during upshifts while accelerating, since it reduces the rpm drop into the next gear.
 

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Here is a good write-up describing torque converter Stall Torque Ratio (STR). I'm not sure how accurate it is.


http://www.ls1gto.com/forums/showthread.php?t=349786

Quoted in case the link goes dead

Howdy. I've recieved a few PMs lately about my posts on stalls and "loose" vs "tight" converters and what STR (Stall to Torque Ratio) to get etc so I thought I would make a post about it that I can refer to. Please feel free to correct me, call me out on bad info or whatever else. I'd like people to be armed with as much info as possible as it expands the enjoyability and results of the hobby

Im going to come at this from a different angle. Instead of blabbing on about all the technical parts inside the converter that make this stuff happen, I'd rather just explain it in average car guy terms. "What does this mean to me?" style.

Generally, the higher the STR number the more it multiplies torque at the starting line or from a dig at a sacrifice of top end efficiency. The lower the STR, the more it multiplies torque over a longer period of time/longer distance at a sacrifice of short term large torque multiplication. Think of a high STR as a shell of buckshot that hits harder close range/hits all at once off the line and a lower STR like a 9mm that hits decent but effective at a longer range. So if dig racing or strip launching is important to you a higher STR will benefit, if rolls or trap speeds are more important to you than a lower STR will fit. STR range is usually 1.8-2.5.


High STR can also make the car hard to hook up. This is how it works in the first few feet:

Lets say we make 450 ft/lbs of torque at the flywheel @ 4,200 RPM. We add in a 4,200 stall, one with a tight/low 1.8 STR and one with a loose/high 2.5 STR. The STR becomes a mulitplier:

450 x 1.8 = 810 ft/lbs of torque at the trans input shaft when the car flash stalls to 4,200 RPM from a dead stop.

450 x 2.5 = 1,125 ft/lbs of torque at the trans input shaft when the car flash stalls to 4,200 RPM from a dead stop.

See why the higher STR could be harder to hook up consistently? Like stated, the other difference is that the lower STR verter will keep that torque multiplied for a longer time than the big STR. So its all about where you want your power and where you use it the most. If you have trouble hooking up for a reason you cant solve with DRs or suspension, maybe consider a lower STR to get the car off the line.

How about the guy who wants a "driveability" converter in the 3,200-3,600 range that hooks up decent? He may want to still consider a lower STR depending on where his cam makes its power. I.E. lets say we have a 3,400 stall but a big cam that starts the meat of its power band around 4,200-4,400. In that case a lower STR (like 1.8) will still multiply some torque by the time it gets to that engine speed where as a big STR (2.5) combo'd on that same cam will be less efficient and have far less multiplication by the time the car hits that engine speed.

Nitrous and Boost are also better mated to a lower STR converter. You'll often here people saying not to run too large of an STR with nitrous because it will "blow through" the converter. The big STR verters are simply too loose and nitrous would be wasted through the converters slipping action. I.E your going to become good friends with the rev limiter. As far as boost, you want it to build as much pressure as possible in the shortest amount of time so you dont want the engine to flash up so fast before it has a chance to build boost and boosted cars are usually top end cars and low STR verters are better suited for that (once again because of the torque multiplication over a longer period of time). Also boosted applications make a ton of low end torque and a high STR converter could aggravate a traction issue.

Shift extension is another variable to consider. A higher STR verter will give you a higher shift extension (the point your engine RPMs fall to after a shift). A higher shift extension may be more beneficial to those with a monster cam that builds all of its power up high. Example: My 2.5 verters shift extension right now is 5,000RPM. Meaning, when the car shifts the RPMs only fall to 5k and climb back up. Technically, my car is a good example of a mis-match currently since it has the stock cam. However, I spec'd the converter for a big 240+ duration can and dont expect to have the stocker in there forever.

Another thing to consider is high STR converters get their high multiplication from slippage. Slippage causes heat. Heat causes 90% of automatics to fail. I wouldnt recommend a high STR verter for a DD car. Example: I have a ~2.5 STR loose 4,200 stall in my bolt on Goat. Built trans, Derale deep pan w/ cooling tubes, stainless braided -6AN trans lines going to a top of the line Derale Atomic Cool 400cfm fan equipped trans cooler and DEX VI (better heat tolerance than DEX III). My trans cooler fan is auto on @ 180'F and off @ 170'F and lets just say once the fluid hits 180 (and it will) I never hear the fan turn off. Its not uncommon for me to see 200'F temps cruising around town not even hammering on it. Comparatively, my buddies '00 Camaro that is lighter, has a tight 1.8 STR 3,400 verter with a basic B&M supercooler as his only cooling mod sees 170'-175'F in 100'F ambiant temps all day long.

So after all that how is a high STR even good and why do people use them? Because they simply PUNISH the street/strip in an all motor scenario from a dig. The high STR converters simply out 60ft the tighter converters all day long for N/A all motor setups. Take my car for example. Its just a bolt on car with maybe ~370whp if I'm lucky. 3,770 race weight, 275 DRs on stock 17s and stock suspension and I routienly pound out high 1.6s and low 1.7 60fts. ROUTINELY. Its not a fluke, nor a "great launch I had one day!" or any of that, its pretty much every time I launch track or street, I run record bolt on GTO stock suspension 60fts. When I blow the tires through the entire first gear I still get 1.9 60fts. This is all in +1,500 to +3000 DA, I could only imagine if I had some of that -1,800 DA east coast goodness.....but I digress. Its all due to the brutal torque multiplication off the line, plain and simple. High STR/stall speed cars are also a blast to drive. It will make your car VERY LOUD if you have a loud exhaust as it is going to be slipping all over the place and causing higher RPMs at lower vehicle speeds. I.E. Off the line and all the way till 4th gear lock up, around 20% throttle my car sits at 3K and sounds like one long gear where you cant even hear or tell if it shifted. People love it. Out of all the bad ass cars at shows/meets mine gets noticed all the time as I roll into the parking lot and the car is at 2,500+ RPM but doing 5MPH as I lumber it into place. Like to rev at people but have an auto? Big STR/stall speed is your ticket. I can throttle pop in gear at a stop a good 500-700 RPM with the car barely even budging and cruising at 40MPH unlocked I can usually rev about 1,500-1,600 RPM without the car moving as well (this will vary with gear ratio, vehicle speed and stall speed...etc). Like to do burnouts? Big STR verters will HAMMER the tires. You've never seen the limiter hit so quick. Learning how to launch a big STR car is a feat in itself. But my point is, with a big, loose converter an auto car is anything but boring to drive.

However, if you have a high STR on a low stall speed converter (2,400-3,200) you probably wont notice much "looseness" in it due to the low stall speed. Also, "loose" and "tight" are subjective like driveability. People have different definitions for what is loose, tight, too big, too small...etc. The best thing to do is try and find a friend with a stalled auto and get a ride and experience the differences.

How do the mfgs figure STR? A good converter shop can give you a close estimate of your STR but actual STR is something only very few builders have access too. Precision Industries claims to have the capability. Other than that it takes a machine about the length of a building and other than PI stating they have a machine, I'm pretty sure only the major auto mfgs have the others. The formula for STR is: exact output torque ÷ exact input torque = STR. Like I said, a good shop should be able to ballpark your stall fairly close. Some may even tell you an exact number but I know Circle D doesnt guarantee a number they just give you their closest estimation. Converter mfgs control STR by modifying the geometry of the turbine and stator blades inside the verter.

So there you have it. Lots of stuff to consider when buying a torque converter for your combo. All the good converter shops know this stuff and your going to want to listen to what your converter builder has to say about your setup. At least now you'll be armed with a little more info to ask them about and I hope you have a better understanding of why they are telling you that you need a certain converter or not. Remember not to take any of my info as gospel and to communicate your goals FULLY to your converter builder as far as driveability expectations, 60ft, trap...etc as the good builders know whats best for your combo. If anyone has anything to add then please do. Also, if anyone has anything to dispute about what I said, please lets hear it so I can edit the post or add in your experience/knowledge. Im a big fan of the spread of good information on this board so I welcome all criticism. Thanks for reading.
 

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converter/flywheel issue

the trans in my 95 caprice is officially toast. i got a deal on a rebuilt 94 tranny from a truck. my brother and me put it in this weekend, everything went fairly easy until i tried to bolt the tc to the fw. the tc is about 1/4" from fw and when it was bolted on didnt engage the tranny. we took tc off fw and slid it back on ( it clunked), moved it forward to fw and it came off trans. we slid it back on trans, got longer bolts, put washers between tc and fw, everything worked. what happened??? i looked through the forum for an answer and didnt find anything.
 

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Further to Jeff's point, I had been running a Yank SS3600 converter behind my stock LT1 engine, and although 3600 sounds high for a stock engine setup, it was what was required for optimum ET. And with the super tight feel/efficiency of the Yank SS series of converters, it really wasn't a compromise even in daily driver duty. Be careful though.....many 3600 converters would be downright miserable/sloppy/unacceptable in that application!
Fast forward to the heads/cam motor in the car now......with the same SS3600 converter, the car was very snappy on the road, more torque to the rear tires than available traction, and anyone driving the car would have sworn it was plenty of converter. But at the first track outing, I was not surprised to find sub-par snap off the line with a dead hook..........unacceptable 60' times in the low/mid 1.6's. Stepped up to a 4200 converter next time out, and it was just barely enough on a warm day to let this engine snap to its powerband at the hit (torque peak on this engine is about 4200 rpm), best 60' now is 1.53. A few more outings will tell if some fine tuning will liven things up sufficiently on the launch or if it really wants more stall.
BTW, I tried this same 4200 converter behind the stock engine and even though the 60' times were the same, it cost about 0.2 sec ET and 2 mph trap speed. The stock cam ran out of wind long before the rpm at which the converter needed to operate to achieve good fluid coupling.
when you had the 4200 converter on the built engine what was the brand of the stall , what type of gearing did you have ? An was it daily driver and highway friendly
 

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Am perty sure u cant use a 94 in a 95 there diffrent
 

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when you had the 4200 converter on the built engine what was the brand of the stall , what type of gearing did you have ? An was it daily driver and highway friendly
It's an ATI Treemaster 8" non-lockup converter. 4.88 gears.
No, not a daily driver. Whether or not the converter is highway friendly is kind of a moot point with the 4.88 gearing....lol!
For most folks' tastes, including my own, I would not call my combo highway friendly or daily-driver friendly. With the stock trans cooler, all it takes is about 10 minutes of spirited driving on a warm day to get the trans temp over 190 deg. With highway cruising, it also settles at about 190. With milder gearing, the temperature issue would be worse.
 

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I have a Yank 2800 and 3.73s, but I want to upgrade my gear and stall but looking for a street strip application. Right now it's my daily but I want it to run atleast in the low 13s before I do a cam swap. Is a circle d 3400 stall and 4.10 gear good

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I have a Yank 2800 and 3.73s, but I want to upgrade my gear and stall but looking for a street strip application. Right now it's my daily but I want it to run atleast in the low 13s before I do a cam swap. Is a circle d 3400 stall and 4.10 gear good
Is that Yank called a "Stealth"? ie. is it a 12" converter? If so, then you're correct in considering an upgrade. Unfortunately, compared to the stellar performance of the Yank SS series (9-1/2") converters in street/strip cars, their Stealth models fall down there with SLP and S-10 converters. Good quality, but not much performance over stock.
I've heard good things about Circle D converters from the F-body crowd, but have no experience with them and have no idea how well they would behave in our heavier cars.
What is your car running now for ET/mph? If you're not in the 13's already with the common bolt-on engine/intake/exhaust mods on an average weight car, then you have other issues to address besides gears and TC, including basic engine health checks before a cam swap.
 

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Yeah it is a stealth thruster I haven't took it to the track yet but once it opens up it will be my first time on the track I'll have a new trans and wanted to upgrade my torque Converter I was thinking in between an SS3200 OR SS3600 but I want it more driver friendly without stressing the trans that's why I'm also thinking of upgrading my gear.

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Personally,I wouldn't bother changing the gear. With a 3.73 already,you have reached a point where going further isn't really getting you much further. Plus,it at least a couple hundred that could easily go somewhere more productive. A new set of drag rubber perhaps?
 

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Ok ill save my money for elsewhere but Im trying to run mid to low 13s or even 12s

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You mentioned the SS3200 or SS3600.......if you planned on keeping the stock cam, I'd go with the 3200 as a compromise between street and strip. Any cam at all over stock will like the 3600 better, and the stock cam works well with the 3600 also. There's another Yank converter I ran for a few years behind my stock engine, which is now labelled by them as a PAS3400. It's the SS3600 with a modified stator that couples up quicker as the vehicle starts to move, so it flashes as high as the SS3600 under full throttle, yet feels tighter under light throttle.
I agree with 1slow; you should leave the 3.73 gears in there unless you need to go into the rear to replace the posi AND you want to chase that last .10 sec of ET
 

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I plan on going with crane 227 cam . Already have 373 gears . Thinking of going to 4.10s thou I have 24 inch iroc rims on 25 series tires on the rear . I want something very quick off the line but good on the hwy . Also want to be able to roast the tires with ease which is why Im thinking 4.10 rear gears . So my question is with 227 cam which Yank converter would be best for my needs and should I switch to 4.10 gears
 

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I have a 1991 9C1. Gettin the tranny rebuilt this week. What stall should I get? I really want it snatching off the line.
 

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Discussion Starter #59
It's highly specific to your setup. Call Yank, Vigilante, ATI or Edge and talk with them. Or find a local torque converter shop; many of them can build a similar converter for a similar price.
 
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