Coyote/auto converter stall?

[Svtfreak]

What stall are you guys with coyote and auto trans running? Granted I’m going with the 6r80 but anyone with 4r70 should be a good starting point. Or can ya guide me to a good source of info to help me choose the right one?

FYI, the kit comes with the stock mustang converter.

[wallace18]

I was told to use a 3000 stall converter for my AOD. The reason given was the light weight of the car would cause it hard to keep stopped with a normal converter.

[Svtfreak]

I was told to use a 3000 stall converter for my AOD. The reason given was the light weight of the car would cause it hard to keep stopped with a normal converter.

How’s that 3k working? My gut is telling to go with that or even 3500 (due to the very low first gear of the 6r80) but that is a very uneducated gut feeling guess.

[JimLev]

My LS3 Connect and Cruise engine/tranny (4L65E) was coming with a 2400-2800 stall speed converter.
Tony Zullo at Factory Five told me pretty much the same thing, the car is too light for the standard converter, get the 3000-3400 converter.
Can't tell you how this is working out yet, my '33 will be ready for pickup this next week.

[donshapansky]

I started off with stock converter supplied by Performance Automatic, the trans was rated for 850 hp. and I thought that the converter would be appropriate but I discovered that without power brakes holding the car at a light was tiresome. After talking with Tony I went with 3200 rpm and now the car is easy to control at high idle when cold and it is harder to brake the rear wheels loose accidentally. It feels slushy to me when driving on the street but the acceleration is incredible and to watch the tachometer under full throttle is amazing, it stays at 7,000 rpm and trans shifts lightning fast. I don't think my superbike is any quicker from a stop or on the highway.

[Svtfreak]

Thanks guys. I will have power brakes so that helps. Most folks seem to be saying 3000-4500 with one guy saying 3700 but he’s a racer so that may be a little too high.

Thanks for the input. Sounds like 3-35 will be just right.

[DaveS53]

There's no reason for a high stall speed converter with an engine that has a stock cam. A light weight car does not require a high stall speed torque converter. My 430 hp LS3 connect and cruise package came with a 2400-2800 stall speed and it works just fine.

High stall speeds will create more heat and poor fuel mileage. I get 20 mpg in town and 22-23 on the highway, driving 75-80. Cruising rpm is 2000-2100, which is 200 rpm higher than you'd see in a 2005 Corvette with the same 4L65E transmission.

[Just puttering]

Just a side question, the 6r80 is so computer controled that people were not able to use it in an after market application. What computer control is available for it now?

[Jay Kravitz]

Listen to what Tony says as he is our Tech/Sales Manager and he knows what he is talking about.

[Svtfreak]

After a few more phone calls, the converter gurus are all over the map. 2400-3700 recommendations. So, after a lot of thought and discussion among friends, I’m gonna try what Dave happened to mention. Since I have he stock mustang one with the setup, it should be about 2800 rpm. I’ll get it going with that. The motor and trans will have to come out anyway for paint so I can swap it then if need be. I’ll know within minutes how well it’ll work and have a good idea from that what I’ll need.

Just a side question, the 6r80 is so computer controled that people were not able to use it in an after market application. What computer control is available for it now?

There are a couple options. Performance automatic and another company make separate stand alone controllers like for the 4r70 now. But, I have the FRPP complete package. The ecu basically has the unneeded OBD stuff eliminated and controls motor and trans. Should run and shift exactly like a stock mustang. Is also tuneable the same way. So it should be absolutely wonderful driveability just like a stock off the floor mustang wokld have. Check out M-9000-PMCA. I don’t think anyone has put one in a 33 yet. I’ve heard that it will fit just will be very close. FFR doesn’t suppport it. I will have to find my own flange for the output shaft (it is a 4 bolt flange, not a slip yolk) but I think forte has them. If not, a donor mustang will have one in a junk yard. And I’ll have to have my own driveshaft made. Physically, it looks like it’ll fit, and the tunnel will be a bit larger than with a 4r70. There will be updates in my build thread, hopefully within the next couple weeks, on physical figment of it. I want to get my hardtop on Tuesday and then I plan on shoehorning the motor and trans in starting as early as Friday.

[myjones]

There's no reason for a high stall speed converter with an engine that has a stock cam. A light weight car does not require a high stall speed torque converter. My 430 hp LS3 connect and cruise package came with a 2400-2800 stall speed and it works just fine.

High stall speeds will create more heat and poor fuel mileage. I get 20 mpg in town and 22-23 on the highway, driving 75-80. Cruising rpm is 2000-2100, which is 200 rpm higher than you'd see in a 2005 Corvette with the same 4L65E transmission.

Dave
I agree with the concept of cam, car weight and stall balance but in our case it's a work around for the stingy brakes on the 33.

Nobody has used the term (flash) in this thread but that's the real issue here. Because of the lightweight car and manual brakes
that require a lot of effort at a stop sign/light we need a higher "flash" speed. The common way to raise the flash speed or the
RPM point where the car wants to start creeping forward is to raise the stall speed and the flash comes up with it. In a perfect world
we would order the right stall for our TQ curve and gearing and have power brakes to negate the flash speed issue.

Surely you see the humor in using the terms "hotrod" and "gas mileage" in the same sentence
Dale

[Svtfreak]

Dale, don’t forget though, I have power brakes. And eventually will huge brakes.

[DaveS53]

If you look on page 366 of the 2018 GM performance parts catalog, they match a torque converter to each crate engine. The stock cam engines have a 2400-2800 recommended stall speed and the hotter cam versions have the 3000-3400 rpm torque converter recommended. Even the 650 hp LT4 only needs the lower stall speed, because it has a very mild cam. GM came up with a special 4L75E trans that will handle the power.

https://html5.dcatalog.com/?docid=00...604bc#page=368

The wimpy brakes included in the '33 kit are just another short-coming that the builder gets to fix. I went through the same process. I use a 1" Wilwood dual master cylinder with Wilwood brakes and an 8" dual diaphragm vacuum booster, and a 4/1 pedal ratio that produces great braking power. A 7/8" master cylinder actually make the brakes a little too sensitive, but I had to try it to see. With the original 7" single diaphragm booster and 1" MC, the braking power was definitely lacking.

You can have a hot rod with great power and good gas mileage, as long as you keep your foot out of it. That's why I would never build a engine with a carb.

[Svtfreak]

Thanks for the input, Dave, but I have to admit that my build shares absolutely nothing with what you are pointing out. While experience and advice is appreciated, I think now it’s ventured off into an area that doesn’t help this particular decision.

[DaveS53]

Well, some FFR '33 cars use the same vacuum booster and master cylinder that I have in my car, plus the same Wilwood brake calipers. Seems relevant to me. Same for the torque converter info - stall speed is based mostly on cam selection, not car weight. My car probably only weighs a couple hundred pounds more than an FFR. I'll make a special effort to refrain from commenting in the future.

[donshapansky]

With the AODE 4R70 using a lock - up converter there is no slippage in cruise mode since the converter is locked up. Mine is set for standard '0' on the PCS module and at light throttle the converter locks at 40 mph which is 1200 rpm great for a cruising around town.

[JimLev]

Just received my kit today with the new 708 page manual.
Page 14 has a note about torque converters...I quote.
"If using an automatic transmission, we recommend a torque converter stall speed of 3500 RPM due to the weight of the finished car."

[Svtfreak]

Just received my kit today with the new 708 page manual.
Page 14 has a note about torque converters...I quote.
"If using an automatic transmission, we recommend a torque converter stall speed of 3500 RPM due to the weight of the finished car."

Great information. But hard to make that guess not knowing anything else yet!
I’m going to try my stock one, but I will be very surprised if, when I take it apart, I don’t wnd up >3000. And that’s just my very uneducated guess.

[Arrowhead]

Just a side question, the 6r80 is so computer controled that people were not able to use it in an after market application. What computer control is available for it now?

US Shift (formally Baumann) makes one

http://www.usshift.com/6r80.shtml

Listen to what Tony says as he is our Tech/Sales Manager and he knows what he is talking about.

Yea but all he's worried about is smoky burnouts