Anybody run a manual trans with BIG power???

[rocketman]

Originally Posted by nitrorocket

Street... I sense a little sarcasm. I put up this post to see what is out there and what people have for experience on this. I have seen some guys running the stock t56 at over 1000 hp and 1000 ftlb of torque, that is why I asked what people think.

Right now, It looks like I either have to trade my $3300 T400 even up for a mildly built T56 and good clutch, or a built 4L80E setup. I have guys that will trade even up for them. Both do not seem to be the best for what I need, But the 4L80 would allow me to buy one of those awesome paddle shift wheels from that sarcastic guy on here, but then I cannot do the standing mile..

I have talked to all the 1000 ftlb torque guys with the stock T56 (real life experience)and they say if you do not power shift it will be fine at my power level. To me that says alot. Sure anything can break, but being that these guys feel confident that I will be fine and they are the some of the fastest hardcore street/drag cars around, that says alot.

I drag raced a t-56 behind a 396 LT1 with no problem till the syrco's went out.I have seen plenty of power shifted T-56's just don't miss a shift

[nitrorocket]

My current top speed is only about 155 mph. Eveb the 4L80 would only get me to 185 mph.

I am just wondering if I should do the 6 speed thing and upgrade it as I have problems. Hmmm.

I have a 12 bolt with a 3 seires True trac and 3.08 gears. To my knowledge this is as low as I can go with a good posi. I have a bullet proof 12 bolt which I am sure you know what they cost. If I sold it I would lose my a** and have to buy a different rear id a 9" can even go that low with a good posi.

I sure wish GM had an auto with 4 forward driving gears.

How long would I have to be in 4th gear for a standing mile? My calculations ahow about 15 seconds after I shift to 4th. FLT told me the fluid would start to get boiling hot if held at WOT in 4th. With my 2 trans coolers with all the air flowing through them, I wonder if a 15 second blast in 4th would get that hot or not? Unfortunatly it is a very expensive trans to experiment on.

[Steve Chryssos]

And what rpm is 155 mph @ 1:1? What is your redline?

[tracy]

"only 185" sounds way to fast for this car. Do you have a pilot's license?

Originally Posted by nitrorocket

My current top speed is only about 155 mph. Eveb the 4L80 would only get me to 185 mph.

I am just wondering if I should do the 6 speed thing and upgrade it as I have problems. Hmmm.

I have a 12 bolt with a 3 seires True trac and 3.08 gears. To my knowledge this is as low as I can go with a good posi. I have a bullet proof 12 bolt which I am sure you know what they cost. If I sold it I would lose my a** and have to buy a different rear id a 9" can even go that low with a good posi.

I sure wish GM had an auto with 4 forward driving gears.

How long would I have to be in 4th gear for a standing mile? My calculations ahow about 15 seconds after I shift to 4th. FLT told me the fluid would start to get boiling hot if held at WOT in 4th. With my 2 trans coolers with all the air flowing through them, I wonder if a 15 second blast in 4th would get that hot or not? Unfortunatly it is a very expensive trans to experiment on.

[nitrorocket]

I have a pilot simulator for the computer, so I am covered!



I really don't know yet as I have not been down the track to see where my rpms are at what MPH exactly. Alot depends on converter slippage. I have been taking it to 7000 rpm because of the 3.42 gears, I hope to only have to spin to no more then 6500 with the new 3.08's.

[rocketman]

Why will a 4L80E not go 200,you have turbo's give it a little more boost to make for the hp loss in a 4L80E,

[deuce_454]

a 4l80e will give you one big advantage, and that is converter lockup, that should be worth some extra mph, also your transmission wont cook at a WOT run

and then ofcourse there si the possibility of addin a paddleshifter

[nitrorocket]

The issue of WOT is in 4th gear with a 4l80. The 4th gear was meant to be a cruising gear and not handlw 800+ fltlb's of torque. That's what I hear anyway.

I cant go 200 mph because the gearing just isn't there. A 4l80 would get me to about 185 mph as the car sits.

[Steve Chryssos]

Correct. I seriously doubt that there is enough friction material in fourth gear to withstand the turbo power PLUS aero drag of your 71 Chevelle AND run that load for an extended period of time. My gear calculator has you running a theoretical 158@7000rpm in 1:1. A .75 overdrive will take you to a theoretical 232 mph. Also keep in mind that your driveshaft will be spinning at 10,000 rpm in overdrive.

But I hate racing on theoretical, frictionless racetracks. Ever try writing with a frictionless pencil? Or dancin' with a frictionless woman?

[quadfather]

Originally Posted by streetfytr68

Correct. I seriously doubt that there is enough friction material in fourth gear to withstand the turbo power PLUS aero drag of your 71 Chevelle AND run that load for an extended period of time. My gear calculator has you running a theoretical 158@7000rpm in 1:1. A .75 overdrive will take you to a theoretical 232 mph. Also keep in mind that your driveshaft will be spinning at 10,000 rpm in overdrive.

But I hate racing on theoretical, frictionless racetracks. Ever try writing with a frictionless pencil? Or dancin' with a frictionless woman?

is the problem with the 4l80e in the convertwer lock-up clutch, or is the o.d. (4th) gear clutch pack not up to the task?