MeanWS6

Was reading in another post that his TH400 was bogging off the line. Is this common? Could just be the driver, but this is why I am gettting rid of the dredded 4L60e -cause it bogs.

Colonel

If you think the 4L60-E "bogs" then you'll hate the TH-400. The 4L60-E has an EXCELLENT 1st gear ratio of 3.06 while the TH-400 has a 2.48 1st (upgradeable to 2.75.)

DERTY

Yeah, it's a little slow out of the hole. It really digs in with higher horsepower setups though. It helps the car launch nicer. So much so that you can downgrade to a 2.10 first gear so that it's geared like a three speed powerglide. Unfortunately that downgrade of a gear costs almost as much as a TH400 does!!!

MeanWS6

well, my 4l60e was bogging so badly until second gear that I was only getting a best of 1.7 60ft times on ET streets - and I was hooking, no spin.
I have a video, if someone can host it. You can hear the car bog at launch, until it hits second gear then the *** end squats down and off she goes. VERY visable in the video.

so, just how noticable is the "bog"? is it bad enough where you lose performance/et times?

BIGBOS

I get bogging sometimes, thats why you need to use the trans brake

My 60's w/out the brake were in the 1.8's all night long, soon as I dropped the pressure in the tires I put it off the brake and had 2 back to back 1.5x 60's.......I could of potentially got it down to a 1.4 if I didn't get kicked out for no cage...

MeanWS6

I guess i can live with it, getting t-brake anyway

what about the shifts, any bog/lag their? How firm are they? Also, when you park the car do you put it in "N" and then set the parking brake.

john kilgore

th400 3.00-1.57 is also availabe

MeanWS6

is the bog only until the Revs get up their, or does it bog until second gear?
How bad is the bog, will you still be able to spray out of the hole?

Fast SS on TNT

iTrader: (1)

No bog with mine, but I use a transbrake. Gear changes are neck snappers too, extremely aggressive!
I tried foot braking my car a couple of times, it's not exactly slow off the line, but there is a noticable difference.

The tranny rocks for launching with nitrous (use a dual relay transbrake setup) or under boost.

BIGBOS

Yea, its for sure slower off the foot brake, but the shifts are neck snapping, more so when its 100% fresh, I know that a neutral to 1st shift while sitting in my driveway would spin one of the rear tires......that was a street tire though

Spl170s

iTrader: (8)

Wouldn't having a higher stalled converter help with this issue? Maybe i'm all wet with this....just curious?

Colonel

Yup.

jimmyblue

iTrader: (11)

Yeah, but with no lockup and no overdrive, you
will have some unpleasant realities to live with
on the highway. That's why the converters you
see for "old school" TH350, TH400 applications
are much lower stall speed than for LS1/4L60E.

V8_DSM_V8again

Either compensate for it with deeper rear end gears.. Least streetable.. or get a custom first gear. It does'nt hurt cruise RPM that way.

http://www.tciauto.com/tech_info/gear_ratios.htm

http://www.tciauto.com/components/lo..._planetary.htm

I'd find the 3.0 first instead..

john kilgore

l also have a 2200-3200 switch pitch torque converter for a th 400