You can cut 1.8 60's with a stock converter, 3.42's, and MT Dr's.

 

I was under the impression that big stalls equal bigger hp numbers on the dyno unlocked and higher mph in the 1/4 (to an extent of course).

 

An unlocked stall is in actuallity a fluid coupler, it will slip and that is why HP number's are lower. Also a higher STR is acheived do to strator design and that design is typically what makes a converter efficient. Typically a high STR means a less efficient converter. But that STR multiplies a butt ton of torque in the lower RPM's and lower speeds.

Now a locked converter more closely matches a 1-1 scenario between the crank and the tranny. You will get a higher HP number because now it takes the fluid coupler out of the equation. It still takes more power to push though an auto so the number will of course be less than an m6, but by locking the clutch, especially in a big stall you will see hp number typically 10% better than before. Locking up a converter in the top end of the track is a trick used to get more HP to the wheels since at that point more HP is better than TQ, and that equates to higher speeds. It's not recommended to lock up a single disk converter at WOT though, you will smoke through it sooner or later. The occasional dyno pull is ok though.

Generally speaking big stalls mean less peak HP on the dyno. Stalled Auto's are all about how the car uses what it has to the best of it's ability. That's why you can have a car that makes 400hp run 10's. Picking a torque converter is not as easy as saying I wan't a 3500 stall, there is alot more too it if you want the best one for the application. Generally speaking if you picked a stock TC and upped the rpms to say 3500 your car would be faster everywhere, due to the shift extension mostly.

Yank is one of the few companies to get the combo right in making a high STR converter and keeping the efficieny up as well.

 

Absolutely not true at all. Have you been reading the posts in this thread? I will take my PT4400 over my old ST3500 or SS4000 on the street any day. It has superior performance over those two in every aspect IMO.....daily driving, highway and track. Before I got the PT4400, I would have taken the SS4000 over the ST3500 any day.

As for street launches, with a little footwork I can get out of the hole just fine. Fine enough to out-launch 99.9% of the cars I'll ever encounter on the street . I just lean into the throttle at ~4000 RPM's until ~35 MPH then go WOT. Usually it'll hook by then, although occasionally it'll light em up.


6-speed, LT's, TD's, lid, ported TB, tuned, traps 110.

 

did you ever race this car with the PT converter in before you had the cam in place? it seems like your modifications may be fairly close besides the cam.

 

Im going off my own experience with stall converters. He said he wanted something good from a roll. You have to remember that all a stall converter is doing is its just slipping the engine into a higher rpm range for quicker lauches. Generally speaking the bigger stalls slips more than the small ones do. I kno some have gain mph at the track, but that might be due to the engine being lugged too much with stock converter and stock gearing. I noticed that with a 3600 stall in my 95Z I was going threw the traps at 6300 rpm trapping 112mph. Now I know its like comparing apples and oranges but my 00'SS m6 trapped 113 at 5000rpm. That being said a tighter converter would be better on the top end side (roll racing). If you find that statement to be untrue then there would no point to people manually locking their converters for more mph.

 

I added the PT after the cam....it felt like I gained more from adding the converter than it did from adding the cam if you can believe that.

Just curious how many converters you've had?

How is that a comparison at all, your Z would have been in 3rd, and your SS would have been in 4th??? Not sure what your point is.

Not the case with the PT series....they are very loose, yet I think you'd be hard pressed to find a converter that offers as much performance on the top end. Yank specifically designed them to offer neck-snapping launches and unbeatable top-end. Case in point....a local member with a H/C WS6 running a Yank PYE 3600....that converter is one of the tightest you can buy. I haven't raced him, but the TA(camera car) in the video above raced this WS6 right after racing me. The WS6 pulled one car to ~140 MPH. I was behind them and had no problem keeping up.

Manually locking a converter picks up MPH for small converters just like it does for big converters. I'm not sure what you're trying to say here.

My point is simple.....in my personal experience with three converters (ST3500, SS4000 and PT4400), each one was larger than the last and each one offered a obvious performance gain. No stalled A4 that I've ridden in or driven has had as much pull as the PT series. It's big, it's loose, and it's the answer to all my converter questions!!

 

That's about 1/4 of what a stall converter does for a car. There is a lot to it, torque multiplication, shift extension, converter diameter, slipping off the line is only part of it.

 

Well I went from a 3500 2.5STR stall to a 4000 1.69STR stall and my mph went up a solid 2+mph and I was slower in the 1/4 because it had very low torque multiplication. Remember when describing a converter as "tight" it's not just about the rated stall speed. Not to mention the same converter in a car making 300hp will not behave the same if the car was making 500hp.

Locking up ANY lockup converter in the top end (3rd) will gain some speed for the reasons I said in my earlier post.

(BTW if you are wondering why I got a 4000 stall w/ a 1.69 STR it is because I did not know at the time)

 

True dat! In my opinion, the Yank PT 4000+ series are the king of the highway convertors. If I were not FI, I would have one.

 

Can't forget the ss3600 weighs like 15 lbs less than the stocker.

 

Hmmmm, so Pt if you aren't going to spray?

 

99hawk, your car moves out...I've shown a couple friends who said a M6 will be faster from a roll over an A4

 

i think i will be calling yank this weekend to try to get their opinion.

 

...not always. I don't think I can beat every 6-speed out there because that's just not the case. But I'll hold my own!

 

I know this is pretty random but wouldn't gears help in this case? If you were to go from the 3.23s to lets say a set of 3.90's (just using that ratio as an example) because of the increase in gear it would accelerate the car faster which in turn would help you from a roll? I know the taller the gear you loose alittle more top end from from lower roll speeds you would want something to punch faster....

 

since this thread was brought back from the dead, I'll respond.

I know M6s are almost always going to be better from a roll , but they thought an A4 could never beat a M6 from a roll [you know, 10 out of 10 times, lol ] and you helped me prove them wrong. That's all.

 

It could....

 

Come on down to Central Mississippi if you really think a big converter is useless on the streets... 4k and up in most of the street cars around here...

 

i have a yank pt 3800 in the car now. however, all of the suspension and such is not on the car yet. i won't be able to test it out for a while. i am in dental school and 34 credit hours per semester isn't fun, not at all.....