Torque Converter Advice

[Thumperbird]

I received a 10" 3100 flash stall from Broader, asked him to reduce it some but it sounds like he can only go down maybe 200 to 300.

Anyway, let's say I want to buy a spare converter so I can try two different types.
Can you guys provide feedback on best brand, model, etc.?
Street use mostly, heavy car, 445 moderate build.

I'm turning 3000 rpm's on the highway.
Rear is effectively 3.8 in first with wide ratio C6, tires are 27" tall.

The 3100 stall seems awful mushy and the tranny is running very warm.
Thinking I want to be in the 2600 to 2800 rpm range.

Thoughts and recommendations anyone?
Thanks.   

[Falcon67]

You need to give him those parameters - I would think he'd recommend an 11" converter for those conditions.  As you reduce converter size, you run into lower limits.  Every "10 inch" converter I've see or used is at least 3K stall or more.  Saturday Night specials, etc.  4.11s and more cam.  Same on the other end - my 9" flashes to around 5K and can't be modified to go higher, so next step if required would be an 8" unit.

To combat heat, you'll want to try keeping the flash stall speed below your cruising RPM.  Stalling above cruise builds heat.  Same deal with my Falcon - 10" 4600 stall converter with 4.56 gears and 10" tire.  Cruising on the street build heat in the trans fairly quick.  You can Saturday Night for about 2 miles, then it's time to stop and let it cool down. 

Edit - the alternative for 3100 stall would be to put in a good size cooler with a built in fan - like the 16 pass Derale I use on the dragster
http://derale.com/products/fluid-coolers/universal/remote-mount2013-10-28-09-53-271073910258/13700-detail

[e philpott]

I ran a 9 inch 5000 rpm stall on street for 15 years and never had heat issues in a C6 with T-Brake , 4.11 gear and 30 tall tire , rode around a week with a temp gun to verify tempeture and finally quit worrying about it and decided Urban legend as it was never any hotter than engine temp after a 60 mile drive  , just get a stall you'll be happy with at cruise rpm , Broader can make you a different unit

if your running a 3.8 gear with 27 tall tire your 3000 rpm is 55 to 60 mph , does that sound about right ? If so you might need a 3.50 or 3.25 gear

[Thumperbird]

It's a wide ratio C6 so final drive is 3.5, rear is 3.5.
70 is aobout 3000 rpm's right now

[Faron]

what is the duration at .050 and the cam lobe separation  , depending on your answer , you may be really disappointed with a tighter converter , its the package that makes the car not just one item , as stated above its best to have the stall speed at or below the cruise rpm , BUT compromises are often needed, just like a recurve its best to know ALL about the combo to make the best decision  IMHO

[Falcon67]

I run a 10" 4600 with a C4 and a temp gauge - trust me, they get hot.  A 2 mile or so cruise at street speeds below 45 MPH will get the temp up close to 200F. At the track, I keep it above 120 and it'll come back from a pass around 180.  I don't care much for trans temps above 180.

[winr1]

Hi jack ....


What's the smallest diameter with a 2200/2400 stall anyone has run or heard of ??

Mild 418 ...



Ricky.

[jayb]

I have to say that I have also never had problems running a converter with a high stall speed on the street.  I started that back in 2005 with the C4 in my Mach 1, which used a 9" diameter 4500 RPM stall converter.  Can ran in the mid 10s.  I had a temp sensor in the trans pan and never saw it go over 180 degrees, engine temp was about 170 degrees.  I put 2500 miles on that combination in one week, during Drag Week 2005.   Never an issue.

I've gone as high as 6200 RPM on the stall, run the Galaxie or Shelby clone during Drag Week, and again never had a problem.  I've usually run a pretty deep gear, like a 4.56, but with a Gear Vendors overdrive.  Doing the math, the engine runs 200-300 RPM over what it would be running with a lockup converter, but that has never bothered me.  And I have not seen any excessive heat buildup.

I think some of the issue is with the converter itself.  My converters are from Neal Chance, and they cost around $1200 each.  I've never hurt one, and always have been happy with their street performance, no matter how radical the car or converter.  I don't think a cheap converter would work as well.

[Falcon67]

Hi jack ....


What's the smallest diameter with a 2200/2400 stall anyone has run or heard of ??

Mild 418 ...



Ricky.

11" should be everything in that range.  TCI, Broader, etc, etc

My converters are built by Freakshow Performance here - he does a lot of work for the No Prep and "SO" people.  His stuff may be a little "looser" than some so more likely to build heat.  But they leave hard and go fast - the "302 in a 3250 lb car with maybe 300 HP on a cold day yanks the front tires" kind of leave.  If I drove the door car a lot more, I'd also move it to a 16 pass cooler from the flat cooler used now.  That'll wait until we get more power and displacement, in case the "top 10 list" thing ever comes back around in these parts.  Not personally interested in running SO or No Prep.  I'm too broke and maybe to lazy to work out running low 5s in the 1/8 on a small tire LOL.

[winr1]

Thanks Chris

I live in Friendswood, Texas so I will look into Freakshow Performance

This will be going in my 65 F100, street use 99%

Want the lightest convertor possible



Ricky.

[Thumperbird]

Broader is going to do a 12" as loose as they can, so somehere around 2500 hopefully.
I figured I need to experience a few flavors anyways to figure out what works best and what I like.

I will keep those other names in mind, Broader also said they could do a custom 10 or 11" but that would cost me so not going there just yet.

I did not have external cooler, engine is typcailly 170 to 180, things got hot but some of that may have been an early on issue with kick down lever sticking partially.

Maybe my tune is way off, just not sure yet, but just too mushy at low speed light leave and up my slight hill driveway for example.

Broader has been VERY good to me working through this.

[Thumperbird]

By the way, cam duration at .050 is 230 intake, 241 exhaust, seperation 110, gross lift .563 intake, .574 exhaust.

[WerbyFord]

Given that cam, your ideal stall is probably 3000 OR MORE for best ET, especially with decent traction which the heavy Bird probably gets?
My 1st guess in the Gonkulator is always to try stall == torq peak.

But, street is always a compromise. I also don't like it when stall speed exceeds cruise speed.

You might want to get some timeslips or even 60ft with a GTECH or something with the 3000 stall, then see how much slower it is with the 2500 stall.
Might as well learn something with all that converter money! It would help others here too.

[Thumperbird]

Yeah, so the traction is surprisingly good, it hooks up like no one's business, the rigid uni-body must be transferring load very well and I have some adjustable coil overs stiffening things up a bit.
I will likely need to buy another converter, Broader is swapping the 10 for a 12, if I  do, it will be a high dollar higher stall.  I think the original less expensive higher stall is just not capable in a 4500 pound car.

This is uncharted territory for me personally and I am making some modifications to the intake system to try and compare low end torque differences.  Air/fuel not dialed in yet either across all RPMs.  I would not be surprised at all if ET's are better with the 3100 stall but it just feels too mushy for me for daily use and I want to experience for myself some of the differences.

I need to experience the other side of the coin, good of torque converter coupling at lower RPM's and see how the engine behaves.

Once I get it all working well as a system I will publish some ET's.

Thanks.

[Falcon67]

Thanks Chris

I live in Friendswood, Texas so I will look into Freakshow Performance

This will be going in my 65 F100, street use 99%

Want the lightest convertor possible

Ricky.

Michael does mostly race stuff, so check with him (Freakshow) as that may not be his main deal.  Broader is up in Weatherford and has a good rep and cna also tailor a converter as needed.  I've bought parts from him in the past, good guy. 

[gt350hr]

   There are three basic Ford 10" converter "cores". The early Falcon 2 speed is the "tight" core and the Pinto and '72-73 351CJ s are considered "loose" because of the fin angles in the pump and turbine. The Falcon is (on average) 500 rpm less stall than the Pinto and 351C ( in modified condition). A loose 12" will (IMHO) be just as soft as the 10" you already have. The Falcon is easy to spot as it often has a ring gear welded to it and the "dents" for the internal fins are less angle than the other two. "I" recommend the falcon core for a tighter 10" OR an 11" ( C4 sourced) . The smaller the converter , the more "natural" stall you will have and the more torque you have , the more stall you will have. "Stall" is merely fluid "confusion" inside the converter before it goes into "fluid lock". Changing internal fin angles and cutting the stator blades increases the "confusion" and gives more "stall". Experience and testing give the converter builder the insight he needs to give you what you need/want. Some are better than others ( to say the least)
    Randy