I'm looking at a Yank SS4000 stall on marketplace I might be interested in but need opinions on if it'll be enough of a gain on my setup over my 3200 Midwest? I'm planning on adding 3.73 gears also soon. I am on a budget, otherwise I'd jump on it. Opinions?

 

Night and day

 

Oh man... Now I want it!

 

Is it with the setup in your sig ?

 

Yeah.

 

Damn, snooze, you lose....it just sold. But now I'll be on the lookout for another one.

I am going to pickup some skinny's for my car tomorrow so I can leave the heavy *** 275/40's at home next time I run.

 

I am also assuming the information in the signature are the correct specs for the vehicle in question...
How about what damn transmission is being discussed?

Why do so many people ask questions/ look for help without providing a relative amount of proper information???

Is the current torque converter the Midwest "Street Performance" 3,200 RPM model?
Looks like the 4L60E stock core 12.5" diameter, probably lock-up, and sells for $180.00...

I unfortunately consider torque converters for these units/ performance use, that are produced for the cheap (Under $600) to be a complete waste of money.
NEVER purchase a cheap torque converter...
That Yank unit is a huge improvement in every aspect, other than possibly being the wrong stall speed for your needs.

Even without enough information on the vehicle; If this is the torque-converter in question...
Then 98CayenneTA is absolutely CORRECT! Night and Day difference and ABSOLUTELY worth it!!!

Now...
-How much does the car weigh?
-How are you launching the vehicle? (Most likely using the foot brake... If a 4L80E, is a Trans-Brake being used)?
-Vacuum power brakes? Stock brakes?
-What RPM are the peak torque and HP occurring at?
-Red-Line RPM and launch RPM?
-What RPM/s are gear changes occurring at?
-Engine tune/ Transmission tune???
-Torque management/ Transmission modifications?
-Do you have a Dynomometer graph to post/ Where and How much average torque and HP are being produced?
-How much engine vacuum is produced at idle?
-How is the rear suspension set-up (Shock, Springs, Control Arms, Pinion angle)?
-Is the rear-end completely stock?
-What type of tires are being used? ***NEVERMIND, now I see the tires***

Has a "professional" recommended a Torque-Converter for your vehicle/ Power-Train?

Dalton from FTI Performance is regularly active and supportive on this forum; I would contact him for a great torque converter, or even just a great recommendation.
He/ They have great products, great services, and will go over any and all necessary questions via a form/ work-sheet to give a proper recommendation.

FTI Performance Torque-Converters and Transmissions: 866-726-8358 *ask for Dalton (FTIPerformance.com)

 

Holy ****! All this just overloaded my brain. It's just a street car that will see the track a few times a year, not a pro car. I would expect to have to provide all this info if I was looking at a new custom built stall. I was just looking at a used one on marketplace. I can try to answer most of your questions though.

4l60 trans semi built...Don't know any more than that.
The converter in it now is around a 10" unit, definitely not 12.5" Been in the car for about 15 years.
Stock weight
Foot brake
Stock brakes
Unfortunatly, I don't know the rpm for peak power/torque because the dyno was reading mph. I attached it.
Engine is dyno tuned/trans is only tuned for shift points/redline which I have at 6500...no torque management
Only thing done since the dyno tune was a 340lph Racetronix pump
Stock suspension and rear until it breaks.....3.23 now but I'm gonna install a 3.73 soon

Like I said, it's not a race car or I'd be looking at a custom unit, just want one for playing around.

 

Okay, so mostly stock everything with some minor upgrades and a partial tune.
I would strongly recommend having some of the transmission torque management tuned back in.
Now a days many of the builders recommend starting around 50% on torque management.

Low power output (that camshaft may be the cause, valve events are not ideal from specs you have stated) and a street car.

Most 10" converters are decent; although I am not very familiar with the model in your vehicle.

I still would call up/ message Dalton @FTI Performance for a recommendation at the very least before you purchase anything new or used.
Most likely he can shed some light on the torque-converter in your vehicle and can compare it to other models.
That way your question ultimately get answered by the best possible people.

Also I would consider a converter from him if the torque-converter in your vehicle is junk in comparison.

Good luck :-)

 

Thanks, I'll look into this more closely.


Never heard of that with TM? I always thought the first thing in tuning a trans was to kill that? I'll look into that also.

 

If you want it to shift like uncle-daddy's el camino with a th350 from the 80's then yea...kill TM and zero all the shift timing tables. It'll chirp the 1-2
It will cause premature wear and a horrible ride quality...but who cares...chirpin the tires gets all the panties drippin'

 

My mistake, I didn't kill it all. Went with this guide when I did it quite a while back. https://ls1tech.com/forums/automatic...tm-w-pics.html

 

If you're on a budget I'd skip the gear swap. In this application, 3.23 to 3.73 is worth almost nothing in the way of ET reduction once you already have a ~3500 stall speed in place. The only significant difference you'll notice with this gear swap is a tighter "feel" at part throttle and a bit harder time getting traction at launch, but potential ET improvements are marginal at best. You might shave off one tenth, maybe less. I wouldn't consider a 3.23 to 3.73 gear swap unless I had already done everything else possible to squeeze out every last drop of performance for my setup and had run out of anything else better to do. Put that money towards a stall upgrade first, IMO.

 

That's a good idea. Plans for the gear swap was for the stall I have now. I am definitely on a budget, got laid off my 35 year job. Thanks

 

I would definitely up the stall and would wait to touch the stock gear until you want a rear. When I did heads cam intake I also did 3.23 to 3.73 at the same time. So I cant say what the gears were worth alone but driving around did tighten up the feel a little with the ss3600. If I were to do it again I would of left the stock 3.23 alone but do gears with a new rear. The 3.73 ended up loud as hell especially after torque arm relocation. The carpet mod didnt help either

 

3200 Midwest vs Yank SS4000, night and day as others have stated.
My recommendation is NEVER buy a used convertor as you can't tell its' internal condition and it would/should be set back to the manufacturer to be cut open and rebuilt which would then take the cost up to buying a new one. Never buy a 'off the shelf' convertor sitting somewhere at a retail place waiting for a purchaser. Yank builds their convertors when they get an order.
Rear end gear change, nice but is only of secondary importance. Take the funds that would have been used for gears and installation and use for rear suspension.

 

I actually would NOT skip/ wait to make the differential gear ratio change.

One of the more significant factors in how the vehicle will accelerate from a stop is the differential gear ratio.
For example; should that Yank 4,000 RPM torque converter be installed with the 3.23:1 gears; and you like the stall/ acceleration of the complete package...

You may find, after installing the 3.73:1 gears; that the torque converter stall speed has increased and now have traction issues, or accelerate slower simply do to the loss of traction/ too violent of the torque being applied to the tires.

Thus; you may wish to change torque converter stall speed to something lower... Something like 3,200 RPM and actually accelerate more quickly holding traction.
I am not saying that this exactly would happen. There are other factors here.

All I am trying to say is that; ideally the gear ratio should already be established.

 

I agree.

If you're having an entirely new rear built at some point, then it certainly makes sense to consider a ratio change to whatever is ideal for your overall package and goals. Otherwise, 2+ decades of data on LS1 + 4L60E combos has proven time and again that the 3.23 to 3.73 swap is worth very little performance gain once a 3000-3500+ stall speed is already in place. The overall cost of the swap and risk of noise related issues (both of which are significant concerns unless you know a really good installer or have excellent skills in this area yourself) don't make this modification worthwhile unless you're one of the few who is excessively bothered by part throttle looseness of the higher stall. The greatest benefit of this swap would be the tightened part throttle feel, not the measurable performance difference (which would be marginal at best). You would need a more drastic ratio change to realize any major performance gains in this application (and then adequate suspension and tires to take advantage of such).

I also agree with FirstYrLS1Z's mindset of being wary of a used converter. Not much you can do externally to verify condition or actual internal specs. I understand the budget concerns, but it could end up being more costly in the end.

 

I work on and build our little 10 bolts, I have 4 housings (2 bare spares 1 with the OEM 3.23s 1 with the 4.56s'). Been working on rear ends since the 60s'. Many gearsets, carriers, axles, parts on hand to build from so costs are minimal.
Drastic ratio change, I went directly to 4.56s'. Picked up a set of used Richmond 4.56s' at a swap meet for $25, installed them on an Eaton posi carrier. Being used, they're noisy but I set them up for wear pattern not quietness. The chambered exhaust makes the noise almost un-moticeable. Put many miles on them including 5 trips to Florida from the Cleveland Ohio area. They're doing fine.
To compensate for the loss of traction due to increased rear wheel torque I'm running LCA relos and QA1 double adjustable rear shocks and Nitto 315x35x17 drag radials.
The 4.56s' provide a very wicked 1st and 2nd gear.

 

Haha, yeah I'd call that a drastic ratio change indeed!

When you have the tools and skills to do a gear swap yourself it greatly reduces the cost, thereby providing a much better return on investment (especially when the ratio change is too small to effect much measurable performance enhancement).