JL ws-6

iTrader: (50)

I have a pretty much full weight car with a 402, th400, 4.10 and a 27 inch qtp, and the hughes converter in my car flashed to about 6100 on the dyno, we're taking it to camaro/firebird day at ned on the 8th of october to test it, I don't have a cage yet so I think the plan is to make a bunch of hard launches, pull 2nd gear and shut it down after the 330 mark so I don't get kicked out, hopefully we can get the suspension sorted out that day. It'a bracket race day, so I'm gonna write 11.85 on the window, and just launch teh car as hard as I can , pull 2nd and start feathering it to try to just finish ahead of the other car... then go to test and tune once I lose in the brackets.... once we get teh car hooking and leaving right i plan to make aone full pass that day, pbviously it's gonna go way better then a 11.49, so 'm only gonna get one shot, but we will see what it does.

The converter I have was originally sonic snake's converter.. he sent it to a guy that does alot of the big mustang guy's converters, he told him that he needed to pick up .3 with a redo to get that car into the 8's last year, and they loosened it up alot, but once up to speed there's very little slip. Before I pulled the M6, at 65 in 4th the car was at about 3400 rpm with the 27 inch tire, now with the th400 it's about 3500, maybe 3600, so there's not alot of slip at speed.... gonna be intresting to see what it does.

BAIN

iTrader: (5)

Where are the guys that are running the 5500 converters (Magnus, 01-Z, Dragaholic, Coach, etc..) We need some first hand experience here

gator's 99TA

iTrader: (2)

i will TTT this untill we get their attention. maybe these guys are actaully racing instead of posting on the net

BAIN

iTrader: (5)

I would be too if the tranny wasn't getting rebuilt again

BAIN

iTrader: (5)

Still waiting for the guys running the 5500 stalls

FANTAZ28

iTrader: (2)

i run a 8 inch ati the same as jugger and maguns, it is a very efficent converter.
i ran a 8 inch coan that stalled to about 6000 while my ati was getting shipped and the coan 60'd better for me but did not mph the same.. with the coan the best mph was 120.... with the ati the car has gone 126 with the addistion of a fast90 set up... but i also added about 100lb's in rollbar and anti sway bar..

my ati stalls to about low 5000's. but if i was able to get the 60foot of the 6000 converter i used but the mph of the ati .... it would be great! but you cant have them both... my ati 60'd within .03 of the coan.

gator's 99TA

iTrader: (2)

so it sounds like these yanks and PI converters that are built as street car converter are being stretched out too far (the 4800-5000 stalls) and they are becoming inefficient? this as opposed to th350/400/glid converters that are more on the lines of being designed to stall at 5000+ rpms?

just shooting at the hip at this point

BAIN

iTrader: (5)

I don't know how efficient my Yank is but the difference in power unlocked vs. locked on the dyno is 46 hp so that doesn't sound to efficient to me


Wonder what I would pick up ET/MPH wise going to a TH350 with 8" ATI 5500?

JL ws-6

iTrader: (50)

I'd guess .5 and 5 mph... give or take. Want a race track performer, put a race track drivetrain in it, works every time.

Loudmouth LS1

iTrader: (10)

Yeah dude, watchin the logs, she sits at 3800 on the line on the t-brake, launch and nitrous hits and she goes to between 5100 - 5200, but it is very efficient, it doesn't get sloppy and start slippin a bunch, I calculated the efficiency once and goin through the traps on the 300 shot at the top of third gear it was like between 93% - 94% efficiency. It seems to me the key to runnin a good time is to get the converter to stall pretty high and still keep the effiiciency on the big end, which is why the converter is so important and you should not go cheap on that, cuz most of the time you get what you pay for!

ALL UC2

iTrader: (4)

HELL YEAH, NOW YOU ARE TALKING!!!!!!!! I HAVE BEEN TELLING YOU THIS SINCE I MET YOU!!!!!!!

BAIN

iTrader: (5)

Does anyone have any direct before and after times from a 4l60e to a th350-400? I would be more inclined to pull the trigger and get a th350 if there was proof (even though I drive my car every day).

fastvette123

I Run A 5000 Stall W/ A 225 Shot. My Car Runs 11:20's On Street Tires. I Think Though If I Had A 4500 Stall It Might Be Faster Because The Motor Never Sees Less Than 5000 Rpm's When Going Down The Track. And The Peak Tq Of My Motror Is Nowhere Near 5000 Rpm's... But The Funny Part Is That I Am Not Going To Change It !!

chpmnsws6

iTrader: (70)

Congrats?

gator's 99TA

iTrader: (2)

good reply...........

BAIN

iTrader: (5)

Well since we didn't get much help as to why the 5000-5500 stalls are being used I found this article on a non-sponcer's site that explains it in more depth. I thought i would post it for future searches or just general information.




High stall torque converters are very desirable in drag race vehicles because they allow the engine to develop maximum torque (say 5000 rpm), before the vehicle leaves the starting line. This type of converter is designed to slip more, or have a higher stall speed then the typical 1300-1900 rpm factory converter. Modifying an engine for increased power will raise the rpm it produces at this new usable horsepower. When the engine power is increased, it will require matching the proper high-stall torque converter. This is important, in order to allow the engine to reach its usable horsepower range before the converter reaches its stall speed, and hydraulically loads the engine. Stall speed is the maximum rpm that an engine can obtain against the hydraulic load of the torque converter with the transmission shaft held stationary.



The best performance is obtained with a converter that has a stall speed slightly higher than the rpm of the engine when it starts to produce its strongest usable power. Too low of a stall speed will result in a bog, and launches will be slow, since the engine will not be in it's usable power range. Too high of a stall speed will result in the engine reaching its peak power range below the rpm. Since the converter can efficiently transfer power, this could result in excessive slippage.



The stall speed is controlled by the converter, engine power, and the ability to hold the transmission input shaft stationary. When engine power is increased, stall speed will go up. Likewise, when engine power is decreased, stall speed will go down. Stall speeds with this type of torque converter are generally rated as what's termed the "Flash Stall Speed" or shock. This is the approximate rpm that the engine will go to when the throttle is quickly moved from the idle position to the wide open throttle with the transmission engaged.



This "Flash Stall Speed" will vary depending upon engine power, rear end ratio, and car weight. It is very important to match all of the engine components; cam, carburetor, torque converter, rear end gear ratio, etc, to work in the same rpm range for the best results. When modifying the engine, do not over cam or over carburete the engine. These are two of the most common mistakes.



Select a rear-end gear ratio that will allow the modified engine and the high stall torque converter to perform efficiently in the rpm range they were built for. A general recommendation, would be to use gears in the following ranges:



3.10 to 3.50 for 2,400 to 2,800 rpm stall converter,

3.50 to 4.10 for 3,000 to 3,800 rpm stall converter,

4.10 and higher range with higher stall converters.



Keep in mind, for a given stall speed, the turbine shaft is held stationary with either the wheel brakes or the transmission brake until the driver is ready to take off. The use of a trans-brake allows the driver to make maximum use of a given stall speed. Stall speed will be limited in cars without a transmission brake. This is because the gear reduction of the transmission and the rear end would provide enough mechanical advantage to overcome the car's wheel brake system. When using the wheel brakes, often the best launch technique for a high stall converter is to leave from a fast idle. This will allow the converter to momentarily flash to a higher stall speed (Flash Stall Speed). This is better then bringing the engine rpm up against the converter and car brakes and also preloading the suspension. When using this launch technique, the engine must idle clean and have a stumble free response to throttle movement.