Not sure what to do .. I've had the 6 speed for some time now and I am running great with it .. But it can't take the abuse that I've been giving it.

I been thinking about going to a TH350 but I am not sure if it will slow me down right now I am making 491 hp and 430 tq to the wheels with a Moser 9" in the car .. what do you guys think would a th350 make me quicker or slow me down a bit over the T56 ??

 

I think it will definitely cost you some trap speed and maybe even a little ET...but the gains in reliability/longevity and consistency might be worth it.
You will lose some highway/streetability as well of course but if the car is trailered for the far away races anyway then that doesn't matter too much.

 

i love mine with 4000 STALL and ITS my daily drive

 

who built your tranny and how is it holding up .. is it a reverse manual valvebody? and what stall do you think would be best for me stay NA ???

thanks

 

Keep in mind too Pete that he has 3.73s also...not sure how 4.10s with a 3 speed auto works out. You might have to change gears as well.
What are the 9" gear options in that (3.70) range?

 

why would I have to change gears .. my final gear would still be 1 to 1 so it should still be fine with the 4.10's he is running spray so I am sure he is trapping higher then me

 

This is my setup and price list from:
Madman & Co. Racing --
$2580 (shipped to Omaha, Nebraska truck terminal)
TH400 Kit included:
Transking TH400-Reverse Manual Valvebody/Transbrake
Ultra Bell-SFI Approved
Transking Stall (you choose what size) with nitrous anti-balloning plate
M6 Tranny Mount (didn't need it because I was running an M6)
Aluminium Nitrous Prepped Driveshaft
Billet Input Shaft ($85 upgrade)
B&M 28K GVW Tranny cooler/ braided hoses/ Aeroquip fittings
Madman locking dipstick/w tube

In addition I also purchased:
$200-TCI Flexplate (or ask Brian about his custom flexplate $$$)
$290-Cheetah SCS gated shifter w/transbrake button
$20-TH400 tranny mount (local parts store)
$25 ARP Flexplate/flywheel bolts (jegs.com)
$12 on washers (tranny mount shims)
$50 Autometer Transmission Temp Gauge
$10 wiring, electrical connectors etc.
$40 1 case of B&M Trick Shift (non synthetic)
$40 ARP Converter bolts

I also upgraded too:
$400 Spohn Torque Arm w/DS safety loop (stock torque arm must be changed) I was running a Mega-Bite from HP Motorsports, and decided on a change.

The install is pretty straightforward. I highly recommend that you use a lift, as I cannot imagine how bad it would be to do this while laying on your back!!

I was worried about losing horsepower going to such a big tranny. Then I took the car around the block, hit the transbrake, wound up the motor and released......I never missed my 6 speed again. I get butterflies still when I hold that little button down.

 

No contest, a properly built TH350 with the right converter will absolutely blow a 6-speed away at the dragstrip. It wouldn't be close.

Seen any 6 speeds running NA 9s (or even mid 10s) with 520 RWHP? I did it with a TH350.

 

Thanks for the info. This will be my route soon

 

I hope your right colonel... right now I am around the 10.7 range. what do you think I will run in the same weather with a th350 ????

 

You pulled 1.49 60s with a 6-speed, right? (That's damn impressive for a 6-speed, btw.) With a 2.75 1st gear and a full tilt converter in that TH350 you should be down in the 1.3s if you can dead hook it. That'll probably bring your ETs down to 10.4s.

 

Thats what I want to hear . My race weight is about 3250 for now. my RWHP is 491 and 430 tq Will I save a few pounds going to the TH350 or add some weight ???

 

The T56/clutch is a little heavier than the 4L60-E/stock converter (52 lbs). Now, make it a 30 lb converter and you're looking at some serious weight reduction. The TH-350 is about the same weight as the 4L60-E from what I can tell. The TH350 converter will be a few lbs lighter due to not having a lockup clutch.

 

a local guy build the tranny for me cost me ($500 with TH400 drum and sprag)
spohn TA $400
B&M shifter $200 with caple
TPS 3900 converter $500( we shim the converter to get to fit with 3 washers)

i got around 4000K street driven and racing it every weekend with no proplem yet

 

the converter i got its get lose when i spary (but its not that bad )
and when i run NA its the best converter i had in my life(if i don't have the spary in my car i'll go with 4500 STALL

 

for more information about the TH350
i went from 4l60E to TH350, i don't go to the track alot but i did couple run ,,with 4l60e i run 6.9 and my best was 6.88 with 1.57 60ft in the 1/8 mile NA when i got the TH350 i run 6.78 with 1.5 60FT on stock suspension.

 

Same TH350 I had in my old blown LT1...it's actually a Transking Tranny and OMFG....that was one of the best tranny's I've had hands down...give brian a call, whip out the CC cause you'll never look back!!! TH350's are the best tranny's besides the 200R4 (But you'll spend around the same)...only good points of the 200 is the 4th gr OD...other than that..I'd have Brian (Madman) put in another th350 in my next LS1...hopefully by then the 4L65's properly built will hold up to 500rwhp no prob and that is as far as I'd like to go w/my next LS1.

 

PS..saw ur running a spohn TA....ditch the bitch if u have a 12 or 9" and go w/Madmans...indestructable and highly adjustable!!!!

 

I have a Moser 12. I like Brian's torque arm. But at the time I was doing all this work, and buying parts, I didn't have the $$$$ for his torque arm.

Spohn has been very good to me, and they make excellent parts. I don't think I hurt Brians feelings much when I opted to skip his torque arm....considering he had a money order for almost $2600 in his hands from me!

 

FWIW, I weighed my t56/stock flywheel/spec III clutch/bellhousing/crossmember against the the lockup TH350 with cast deep pan/TP4200 converter/flexplate/adapter plate/Yank crossmember with torque arm mount and the TH350 stuff was 15lbs less..