Ok guys, this is probably a stupid question, but hypothetically if you were racing from a roll, would a 2800 or higher stall be of any benefit or is the ONLY benefit of a stall if you are racing from a stop ?

I have never driven a car with a aftermarket TC, so I don't know what the feeling is like. I also can't imagine what the difference is off the line either, and how that difference feels. I have just heard that it is impossible to drive in the rain or snow after getting a higher stall TC.

I know it is a great mod to do, but any descriptions, in your own words, of what it is like to drive or race from a roll with a higher stall TC would be appreciated.

Thanks ! !

 

To be honest with you I don't know........ I had a 2800 stall converter in the car for a day before I had to park it due to a blown headgasket. I really don't think it helped much from a roll. But again, I only had one day to evaluate. From a stop it was great, the RPMs came right up into the powerband, and the RPM drop between shifts was less.

John

 

It helps at all RPMs and is the best bolt-on mod you can do. A 3200 took .4 off my 1/4times when it was a bolt-on car..

 

Ok... here is what I don't understand.

so with a 3200 stall your car sits at idle just like stock but then the light goes green and you launch. Your RPMS jump to 3200 automatically before your car moves right ?

How would it affect or change anything at speed ? I can see how it might affect your shifts at speed, but does the car stay at 3200rpms or higher the entire time you are on the freeway etc.. ? ?

That is (I guess) what I don't understand.

If I am (hypothetically) going 60 mph and punch it, what will a higher stall do for me at this point vs. stock ?

 

If you take off normally at a light, it won't flash all the way to the stall limit, but the rpms will go a bit higher than the stocker. In the rain it doesnt make any difference traction wise to me anyway, as long as you have decent tires you'll be fine. Snow may be quite a bit harder. But WTF are you doing driving your car in the snow Way too nice to be subjected to that.

When you hammer it is when it really jumps up to the higher rpm and gets you going quicker, but you need a much better tire to get traction. Especially when dragging. Once you get on the highway, as long as you get a lockup converter, it will act just like stock. The TC locks up, and the rpms go to the same point they would with a stocker, because theres no TC "slippage"

HTH a little.

 

Ok so either stock or aftermarket, if I am cruising along at 60 mph, the TC should be fully locked up with no slippage (assuming a stock, good condition transmission) ?

So from a 60-120 run, no benefit would really be seen by the addition of a higher stall ?

Lockup doesn't depend on RPM's at that point, so the only advantage of a aftermarket TC are at the track or from a dead stop ?

 

Yes and No.

When your cruising normally, the TC will lock up at the same mph and be at the same RPM as a stocker. Now, as soon as you go to accelerate somewhat hard, the TC will unlock, and the RPMs will go higher than stock. So basically speaking, Whenever you're accelerating, the RPM's will be higher than a stock stalled car. Now there's different opinions on whether or not a high stall will help from a roll. I feel they will. If your cruising at 70 say, then hammer it, the TC will unlock and the tranny will downshift. Now with the converter you'd be about 1000-1500 rpm higher than stock, which IMO would help you get going. But all in all the biggest difference wil definitly be from a stop, assuming you get traction.

 

On tunercat, the TQ lock up is based on % throttle position and the what mph in a particular gear. So you can change what mph the tq lockups in 2nd, 3rd, 4th for that particular amount of gas you are giving it.

Stock A4 TQ Engage Table
%TPS 2nd 3rd 4th
0 255 46 46
6.3 255 46 46
12.5 255 46 46
18.8 255 46 46
25 255 56 56
31.3 255 70 70
37.5 255 79 79
43.8 255 93 93
50 255 255 255
56.3 255 255 255
62.5 255 255 255
68.8 255 255 255
75 255 255 255
81.3 255 255 255
87.5 255 255 255
93.8 255 255 255
100 255 255 255

So anything over 50% throttle the TC will not lock up using the stock values. Their is a similiar table for TQ disengage also.

Jeff D.

 

Wow great info poorman !

so tq lockup... is that a good thing or bad thing for performance from a roll) ?

I had my PCM tuned by Bryan (pcmforless) and he set it for aggessive shifts, maybe he changed some of those values ? I will have to check with him...

So what I am hearing so far is that a aftermarket TC + programming the lockup values would be beneficial in any situation where you are WOT (even if it's from a roll) ?

 

Ok, I see what you are saying now. With a 3200 stall converter, you probably won't see it stall to 3200. Maybe if you are at a dead stop and flash the converter IE stab the gas it might. How much higher the RPMs jump depends on how hard you are on the gas. With my 2800 stall converter it feels looser, but not bad. When I accelerate normally from a light or something the RPMs get up to about 1500 or so.

Then, when you are on the highway, the RPMs will be somewhat higher than normal until the converter locks up. The stock converter locks up at about 45mph with stock tuning. So that's the RPM drop you see there. No matter what RPM the stall is rated at, the lockup will get you back to stock cruising RPM when it is locked.

I am undecided on whether it helps or not from a roll, but I can say that it won't hurt you any. If you get a converter, you better get some drag radials at least or it will be a slide show!! My car on drags with the converter and a blown headgasket would burn the tires halfway through first from a roll on

John

 

How do you figure out what stall you need??? RWHP vs Weight?? or do you need a dyno report

 

Someone told me to pick a stall rating that is 500-700 rpm below your torque peak. Since I'm not all out racing the car I just went with a 2800, it's got great streetability.

John

 

To hell with the 60-120 race, put in a 2800 and coast along at 30 mph and nail it. He He He, trust me after you get the car straight again, look in the mirror, and i guarntee you will be smiling. lol, prorac1