Auto guys, converter stall question.

[2bscrewed]

I was just wondering what stall you had in your converter, and how it does off the foot brake.
I know your power/boost curve should determine it, but too high of a stall in a street car can be annoying. So I wanted to see what you guys were running, and how they performed.

 

[whtcobra1998]

What trans are u running and when do you start making boost? Mine is 3k but will go 3200on the trans brake. It's to tight for my car, next time ill run a 3800-4k. My car start to go full boost at 4k.

 

[2bscrewed]

What trans are u running and when do you start making boost? Mine is 3k but will go 3200on the trans brake. It's to tight for my car, next time ill run a 3800-4k. My car start to go full boost at 4k.

I'm getting a 4R70W from BCA. I'm looking at probably a 3400-3600 stall because it's 95% street car, and I think over 4k stall would be annoying on the street. I am just looking to see if I am way off on my thinking or not.

My car with the 6 speed on a non loaded dyno jet was fully spooled to 23#'s by 4600 rpm, and starts building boost as soon as you floor it, even down at 2k rpm it makes 2-3#'s.

 

[whtcobra1998]

aode gearset will load the car better than the 4r70, you could also run a higher stall and than lock the converter in second gear for no slip, just have to get the correct manual v.b. to do that. my p.a. valve body doesn't allow me to do that

 

[justinschmidt1]

aode gearset will load the car better than the 4r70, you could also run a higher stall and than lock the converter in second gear for no slip, just have to get the correct manual v.b. to do that. my p.a. valve body doesn't allow me to do that

I have a built 4r70w with a 3800 stall setup to lock as soon as it shifts to second gear.

You can do it if you have a good tuner.

 

[2bscrewed]

I have a built 4r70w with a 3800 stall setup to lock as soon as it shifts to second gear.

You can do it if you have a good tuner.

I'll be using a full manual VB, with lock up on a switch.

 

[Juiced46]

Mine is a 3800-4000 stall. No issues with street driving and not annoying at all. Car cruises just fine. Let off the gas from a stop and the car moves.

I cant footbrake it and build boost on the street, it will start to spin the tires before it will build boost. On the T-brake it will flash up quick to around 3500ish, basically full spool within a sec or 2 and will push to around 4800 or so. I use the 2 step to limit it around 4000-4200 for the track.

If you go to tight you may have issues with spooling on the Tbrake

 

[Turbo98]

I'm interested in this as well. So is the main reason for a higher stall to build more boost off the line? Other than that, what are the advantages and disadvantages of a low or high stall for a street car?

 

[y2k2gt]

It's not one fits all. It all depends on how your setup works. It has to be loose enough for the turbos to spool, but tight enough to not slip on the big end of the track. The lockup should give the best of both, but locking it up with big hp could cause issues.
Seems most with the lockup only lock it on the street for better mpg.
The more boost you run on the brake. The more it will stall.
Here is how mine acts on the street in 2nd gear with a C4.
[nomedia="http://www.youtube.com/watch?v=kXblGyaBpfk"]YouTube - 2nd gear Twin turbo Mustang[/nomedia]

 

[C666]

The guy making the converter needs to know what he is doing went through 5 converters with the 4r70 PTC got it right the first time it will spool the big turbo and is tight up top ran 2mph faster then the tightest converter (I have that lightly used PTC converter FS)

Now I have a glide with custom ptc it is streetable footbrakes to 3800 will go to 5300 on the transbrake but only slips 5% up top at 154mph trap.

 

[Turbo98]

PTC got it right the first time it will spool the big turbo and is tight up top ran 2mph faster then the tightest converter (I have that lightly used PTC converter FS)

What is the stall on this converter?

 

[jpcobra]

Would a 3200 be a good stall for a bolt on 5.4 with 4.10 gears out back?

 

[32Valvefox]

in my convertable with a 4r70w manual vb i had a 4,000 stall on the street. car didnt move from a dead stop at a traffic light till about 2200rpms. i just put a (supposed to be)3300 stall in it. we'll see how it reacts this spring.

 

[C666]

What is the stall on this converter?

It was custom built loose enough down low to spool an 88 but extreemly tight up top. What it will flash/stall to will depend on power as with all converters...

For exanple my current PTC in my glide will flash to 5k leaving at 12 psi and 6k leaving at 16psi but only slips 5% at 154mph

 

[2bscrewed]

in my convertable with a 4r70w manual vb i had a 4,000 stall on the street. car didnt move from a dead stop at a traffic light till about 2200rpms. i just put a (supposed to be)3300 stall in it. we'll see how it reacts this spring.

Ya, that's what I don't want to happen.

 

[Turbo98]

Ya, that's what I don't want to happen.

Exactly.

In most cases, it sounds like hit or miss with the converter to get the exact balance for the track and street. In all fairness to the converter manufacturers, unless they get to drive and dyno the car before they make the converter, it would be tough to get it just perfect for somebody's driving style/goals. I suppose some manufacturers could be fortunate enough to get it right for every customer every time but that seems impossible with every combo being different-no matter how "good" they are. But I'm sure some will get closer than others though. Just my observation.

 

[2bscrewed]

Ya, I sent Circle D my dyno sheets, intentions, car specs, and expectations, hopefully they get it close the first time.

 

[Juiced46]

in my convertable with a 4r70w manual vb i had a 4,000 stall on the street. car didnt move from a dead stop at a traffic light till about 2200rpms. i just put a (supposed to be)3300 stall in it. we'll see how it reacts this spring.

Thats strange, who did the converter?

My car with a 4000 stall I let off the brake it starts going @ idle. I built another Th400 Turbo Cobra with the same results. So you are saying if you let off the brake hit the gas the car will not move at all until 2200?

 

[y2k2gt]

^^I agree that doesnt sound right at all. I take my foot off the brake and it moves also.
Drives normal untill you get on it.

 

[BLK_03]

I was just wondering what stall you had in your converter, and how it does off the foot brake.
I know your power/boost curve should determine it, but too high of a stall in a street car can be annoying. So I wanted to see what you guys were running, and how they performed.

You're really going to need something that comes up to about 3800, mmmaaayyybeeee 3700 on the tbrake Shane. I've had a converter that flashed to 3400/3500, and there just wasn't enough there to get the turbos spooling. Now.... there is a little that goes into that... N/A power (since the engine is essentially n/a before spooling), timing, fueling, compression, cam timing, etc. It all matters. A converter that flashed to 3400 rpm in a 8.5:1 compression car will probably flash higher in a 10.5:1 compression car, all else being equal. You can try some tricks in the tune to overcome a converter that is tight. Leaning the tune, adding timing...all below a certain RPM point (before spooling) and tuning the car as if it is n/a can help get up to that RPM where the turbos come on.

Once you get that sweet spot, where the converter allows proper spooling, hopefully it's tight enough up top and you don't push through it. It's a fine line. If you loosen the converter to help spool, it's going to be looser up top. You really have to get with a company or person that has quite a bit of experience with your given setup.

With that said... my converter is probably a little loose after upping the compression. So... even with a loose converter, it's not like a super high stalled thing on the street. It's like Dave mentioned, leaving a stop sign is anti-climatic. Now, if you punch it, and go WOT from a stop sign, yes the RPM will come up a bit. But shit... I was giving the car some RPM with the Spec V and DFX when I was 6 speed to help minimize chatter. Similar, IMO.