How much horsepower over stock can the Z's Auto tranny handle?
 

Just wondering, i know most honduhs wont handle much more than 20% over stock or so, so what do you think the average horsepower could the auto tranny take on a daily basis? And the max? Ive heard 350-500, can anyone nail it down for me?

Automatic transmission are all rated by torque limits for 100,000 shift cycles.
The Jatco RE5 is rated at 333 lb/ft. BUT this assume oem engine torque control during shift by timing reduction [advance goes to zero then ramps back up to 20].

so it is about 20% over stock, ok

350-400whp and whp/lbft is easily managable. We are looking for a local subjet to test out our new FP valve body upgrade Interested? :)

hmmm maybe :D

I should have my built motor running soon. I will have a 500whp(not sure on tq#) street tune for DD so I'll let you know how it holds up. I do have some tranny mods but not a completely built tranny.

Sharif, PM me if you want me to try your VB.

Convert HP to torque by multipling by 5252/rpm...........500 hp at 6500 5252/6500= 0.808 or 404 lb/ft obviously in excess of oem rating of 333.
412 flywheel HP at 6500 or about 330 rear wheel HP would seem to be ok for a lesser while.

Really depends on ratio of WOT vs lower load shifts.

Are you using the 6500 number as where the car makes peak whp on a dyno. If your making whp over 6500 you would just use that rpm #. What steps can be taken with the tranny to achieve higher tq #'s. I know tq creates heat issues. Any input is appreciated because I'm trying to make this tranny work for me and not go built or T350-400

did anyone try this guys VB? Im looking to push 400-500 on this automatic and am thinking my trannys gunna need help... any info helps NVM... seems they are both Banned for some reason...

The stock trans will be fine at the power levels you want. As long as you're using the stock ecu or a stand-a-lone that you can tune the transmission to work with the power. That's where most guys fall short.

valve body
 

transgo valve body upgrade worked well for my vortech at 377 rwhp...switched to a fully built IPT with TQ converter, deeper pan and 40 row cooler for my TT setup.

rcdash is the man ... he had a high whp auto for years before converting to 6MT. You should PM him.

VB
 

The transgo valve body modification kit REALLY helped at 400 rwhp, and gave hard, quick shifts, thus saving slippage and clutch paks.... 500 rwhp is probably going to need a fully built transmission from IPT, SFR or some other company utilizing more clutch paks. Possibly a new TQ converter as well.

Every now and then a built trans comes up on the want ads...check there....usually 2500-3500 used.....a new one is minimum $3500 (SFR) and up to 5000 with TQ converter (IPT)....Ask me how I know.