StupidFast

Maybe Yank didn't understand the amount of weight your truck has. The more weight the more of a stall. You told them you have a truck but did you say that you have a 5000lb plus truck.
Also with nitrous use you usually want a tighter converter, more so than turbos or blowers. Nitrous will usually make its peak torque about 200-400 rpms after the hit, in my experience. It would be hard to pick a converter when looking at a dyno instead of what rpm you squeeze it.
I maybe wrong but, I think that the weight is a bigger oversight than the power. And of course with the weight and the juice the difference would be greater.
I have seen a few people running a lock-up converters down the track. The only problem is that it is extremely hard on parts. I recently saw a 200 tranny sheer the input shaft. He would lock-up the converter after shifting into 2nd.
My opinion.

Black Blown 02

Parish, Maybe that thing would stall like it should if it were in a car. All that extra weight and power would take alot tighter converter than the regular 3400E.It sounds like thats more along the lines of what you got.

I would think your 6.0 150 shot should stall at 3600 tops if it were going to stay under 4000 with the t76 409.

Have you looked at Neil Chance converters? That might be your best bet with what you are planning on running.

Otherwise, maybe Mike can tighten that one up for you.

Good luck.

Flyer

iTrader: (1)

From what I've gathered, torque is what gets you the good launch ... HP is what gets you the high trap speeds.

BigKID

iTrader: (5)

Locking up the converter is a 'bandaid' fix, IMO. I would call Mike back and explain to him exactly what you want and all the specs of your truck and see what he offers to do about it. I also think Whitt may have a point with Yanks and the 80's. Hopefully Yank will make it right for you.

Hit Man X

Lemme add a few ¢ on this... ever wonder why turbo diesel trucks aren't super fast from the dead stop? Most of their converters are WAY over stalled. The torque peak is at ~1800rpms and the converter stalls from 2000-2200rpms typically. That's pretty much useless as you are defeating the purpose of all that power. SAME premise goes for you...you are stalling over the useable area.

I think these trucks are rated to max torque at 4400rpms and you are coming out at 4600-4700 you are losing probably .1-.3 off the 60' that way.

If you plan to lock that converter in 3rd, I'd see if Yank can make that clutch a multilayer setup. I don't think a single clutch will last too long like that. I'd say around 600rwtq and that's gonna slip locked up underload...that's a very feasible amount w/ a large turbo, nitrous, and cubes.

Granted my comparison is from the diesel world, it still is the same idea...

onyx

.. oh my god.... i look at this thread. i try to comprehend the thread.... i still dont undertstand the thread.

Hit Man X

parish8

iTrader: (6)

finialy got time to go out and do some logs and it is raining, well believe it or not the truck hooks good in the rain. i couldn't do a regular hole shot with the nitrous but i was able to do some NA runs and a 2nd gear start with the 125shot run.

in this first chart i locked the converter right after the 1-2shift on the last 2 runs and it seems to help, more runs would be nice to prove this out but if i can pick up time NA by locking the converter i would have to pick up even more with the nitrous. my shift extension is about 4800 with the nitrous and 4400 without it, i am missing out on a ton of tq with the nitrous and a 4800shift extension. Colonel was right, shifting at 5500 or 6000 didn't change my shift extension at all.



here is the 2nd gear start with a 125shot.



now i have 2 questions, what is my "stall" speed, and what should my stall speed be for a motor that has peak torque at 4200rpm?

BigTex

iTrader: (16)

I think someone else said that in their first reply to this thread:

I'd be looking for a converter that will stall no more than 3600-3800. But finding one that does that with 800+ ft pounds will be tricky. I wonder what the stock converter will stall if you threw 1000 foot pounds at it?

BigKID

iTrader: (5)

Going would be my guess.

Parish.. From the EFI log, I would say it flashed to 4500 where you have the line onthe graph. Once you hit it, it stayed between 4500-4600 the whole time.