B'klyn9C1

In planning for my monster motor in my 1995 Caprice 9C1 I would value your opinion on what transmission I should put behind it.

I am really intrigued by the new 6L90E that is going in the new Vette and Pontiac G8. A six speed auto with a 4.03:1 first gear(I can go back to the B-Body's stock 3.08 rear gear from my present 3.73's) and manumatic capability.

My question is this new tranny worth it or should I just stick to a performance built 4L60/65E with all the aftermarket goodies that has came on line in the past few years??????

My present 4l60E is a performance built and I don't hear as many stories of 4L60's blowing up behind high HP/TQ built LT1's and LS1's, LS6's and LS2's like I used to. I noticed that the 6th gear overdrive ratio is no taller than the 4th gear OD on my 4L60E so where is the big gas savings as the .50 OD on the T56????

A big contributor to the impalassforum Dwayne Jennings aka 96capriceMGR suggested that the 5.7 liter plus displacement Chevy Small Block V8(all Generations) doesn't really need those multiple gears like 5, 6 ands 7 speed transmissions like the European and Japanese motors do because of the SBC's big massive torques curve as compared to the Euro/Japanese small displacement high RPM motors with their narrow torque bands and also that a high quality 2500+ RPM stall torque converter (like the ones produced by Yank, Vigilante and Edge) function as kind of intermediate gear sort of but not completely like the Gear Vendor units between the relative broad ratios of our 4 speed OD trannies by always multiplying the torque coming off the flywheel when out of lock up and especially below the stall speed. And the shifting of the additional gears just takes up time in our case. Tell is there any truth to his hypothesis????

Another thing I noticed is the the 4L60E has a svelte weight of 163 LBS as compared the 6L90E's 225 LBS.

Your thoughts and comments please ?!?!?!?

So which is it?? A performance built 4L60E or 6L90E ????

Hennytime

iTrader: (33)

i think speartech is still working on the harness and no one has done the conversion yet, but gl haha

99Hawk262

iTrader: (19)

4L80 is your friend. I don't think any 4L60 will hold up for long. I have a buddy that got a 80 out of the junkyard and put it behind his Turbo 402 SS and it worked great. This was a stock tranny too.

Ragtop 99

iTrader: (7)

There are a few FI vettes running the A6, but not many in the 600+ RWTQ class. That is well above the rated level for the tranny. Are you prepared to experiment at that level of power or do you want something pretty reliable? A 4L80e and a 3000 stall will hold that power and fry almost any streetable tire.

Gilbert@Ace Racing

A 4L80E makes perfect sense in this situation. The 4L60E was originally engineered to take just under 400 lbtq and we can take it well above that... but anything in the 600 h/p- tq range will be hanging it out to the point where it makes sense to step up to the next unit.

There aren't any aftermarket conversion solutions that I am aware of for the 6L80E.

If you would like to know more feel free to p.m. me or just give me a call and we can discuss some options for your build.

g

ChocoTaco369

The best 4L60E in the world isn't going to hold up against that type of torque very long. The 6L90E would probably be a great choice as a transmission, but I don't think anyone has figured out a way to make a swap possible yet. The best - and IMO ONLY - choice for you is the tried-and-true 4L80E. It'll take 600rwhp/600rwtq without even blinking for a long time, you'll keep overdrive and it'll remain streetable on the highway and you can build that baby so have some intense shifting, so I hear.

philntx

iTrader: (8)

The Corvette has the 6L80E Trans.

There are more than a few cars on the Corvette Forum that are in the 550+ range with FI using the 6L80E Trans

According to John at Speartech, there are several conversions running now with the 6L90E trans using his harness.

Gilbert@Ace Racing

Interesting. I was unaware of that information. I'll call John tomorrow to pick his brain. Thanks for the info.

g

ChocoTaco369

Is there anyone experiencing problems with the 6L80E yet? I've searched and I can't find ANY problems out there. They've been in use for what, 2 years now? Surely someone has broken one.

I want to know what the limit of a STOCK 6L80E/6L90E is. I want to know what RPM/rwhp/rwtq breaks these suckers. I can't find any issues with them. It's astounding.

I wanna know everything about this trans. What is its biggest weakness? What is its max power/torque/RPM limit? How much can they take built? What parts are available to build them up and make them stronger? How hard can these babies be set to shift? I want to see an automatic bark the tires in the 1-2, 2-3 and 3-4.

Gilbert@Ace Racing

A cursory search produced this information... Notice the steep ratio change between 1st and 2nd gears in both units.


2007 Hydra-Matic 6L80 Transmission ( MYC ) 52206
Type: six speed RWD / AWD, electronically controlled automatic overdrive transmission with torque converter clutch. Clutch-to-clutch architecture, with integral Electro / Hydraulic Controls Module
Maximum engine power: 469 bhp ( 349 kW )
Maximum engine torque: 439 lb-ft ( 595 Nm )
Maximum gearbox torque: 664 lb-ft ( 900 Nm )
Gear ratios: MYC
First: 4.03
Second: 2.36
Third: 1.53
Fourth: 1.15
Fifth: 0.85
Sixth: 0.67
Reverse: -3.06
Maximum shift speed 6500 rpm
Maximum Validated Weights: ( Target ) GVW: 8600 lb ( 3901 kg ), GCVW: 14000 lb ( 6350 kg )
7-position quadrant: P, R, N, D, X, X, X ( X = available calibratable range position )
Case description: 3-piece ( Bell, main, extension )
Case material: die cast aluminum
Shift pattern: (2) Three-way on/off solenoids
Shift quality: Five variable bleed solenoid
Torque converter clutch: Variable Bleed Solenoid ECCC
Converter size: 300mm ( reference )
Fluid type: DEXRONŠ VI
Fluid capacity: w/ 258 & 300mm converter 258mm: 9.7L ( 8.22kg ), 300mm: 11.9L ( 10.1kg )
Transmission weight: w/ 258 & 300mm converter 258mm: Wet: 94-96kg ( 207-211lb )
300mm: Wet: 102-104kg ( 225-229lb )
Pressure taps available: line pressure
Assembly Site: GMPT Ypsilanti, MI
Applications: Chevrolet Corvette
Cadillac XLR
Cadillac XLRV
Cadillac STSV
GMC Yukon Denali
GMC Yukon Denali XL
Cadillac Escalade
Cadillac Escalade ESV
Cadillac Escalade EXT
Holden Commodore
Holden Statesman

Available Control Features: Multiple Shift Patterns ( Selectable or Adaptive )
Driver Shift Control ( Tap Up / Tap Down )
Enhanced Performance Algorithm Shifting ( PAS II )
Next Generation Tow / Haul Mode
Engine Torque Management On All Shifts
Altitude and Temperature Compensation
Adaptive Shift Time
Neutral Idle
Reverse Lockout
Automatic Grade Braking
Additional Features: Oil Life Monitor
OBDII / EOBD
Integral Electro/Hydraulic Controls Module ( Tehcm )
Control Interface Protocol - GMLAN


2007 Hydra-Matic 6L90 Transmission ( MYD ) 71706
Type: six speed RWD / AWD, electronically controlled automatic overdrive transmission with torque converter clutch. Clutch-to-clutch architecture, with integral Electro / Hydraulic Controls Module
Maximum engine power: 452 bhp ( 337 kW ), Diesel: 300bhp ( 223kW )
Maximum engine torque: 531 lb-ft ( 720 Nm ), Diesel: 520 lb-ft ( 705 Nm )
Maximum gearbox torque: 885 lb-ft ( 1200 Nm )
Gear ratios: MYD
First: 4.03
Second: 2.36
Third: 1.53
Fourth: 1.15
Fifth: 0.85
Sixth: 0.67
Reverse: -3.06
Maximum shift speed 6000 rpm
Maximum Validated Weights: ( Target ) GVW: 15000 lb ( 6803 kg ), GCVW: 21000 lb ( 9525 kg )
7-position quadrant: P, R, N, D, X, X, X ( X = available calibratable range position )
Case description: 3-piece ( Bell, main, extension )
Case material: die cast aluminum
Shift pattern: (2) Three-way on/off solenoids
Shift quality: Five variable bleed solenoid
Torque converter clutch: Variable Bleed Solenoid ECCC
Converter size: 300mm ( reference )
Fluid type: DEXRONŠ VI
Fluid capacity: w/ 300mm converter 300mm: 13.0L ( 10.8kg )
Transmission weight: w/ 300mm converter Wet: 109kg ( 240lb ) estimated
Pressure taps available: line pressure
Assembly Site: GMPT Ypsilanti, MI
Applications: Chevrolet Suburban
GMC Yukon XL
Chevrolet Silverado HD
GMC Sierra HD
Available Control Features: Multiple Shift Patterns ( Selectable or Adaptive )
Driver Shift Control ( Tap Up / Tap Down )
Enhanced Performance Algorithm Shifting ( PAS II )
Next Generation Tow / Haul Mode
Engine Torque Management On All Shifts
Altitude and Temperature Compensation
Adaptive Shift Time
Neutral Idle
Reverse Lockout
Automatic Grade Braking
Additional Features: Oil Life Monitor
OBDII / EOBD
Integral Electro/Hydraulic Controls Module ( Tehcm )
Control Interface Protocol - GMLAN

performabuilt

iTrader: (25)

We would like to give the 4L60e A shot for you and we will warranty it.

383lt1impala

iTrader: (33)

i would go with franks 4l60e a good 80e will run what about 3000 and up and franks 60e will run u about 2300 for a stage 2 with a t.c!!! give him a shot if he says he'll warranty it he will!!

ChocoTaco369

I've seen all the specs from GM many times. Everyone knows GM underrates their transmissions, and it seems the 6L80E/6L90E is no different. I wanna see what its real-world breaking point is. If there are 500+hp FI guys on Corvetteforum running stock units, it seems it can take a lot more punishment than the spec sheet says.

performabuilt

iTrader: (25)

We have a guy runing our level 1 at just under 500 rwhp so it would be interesting and yes we would warranty it. Sounds like and idea! Let see how far the level 2 will go level 3 even better

performabuilt

iTrader: (25)

I will go further what ever you pay for the level three if it dosent work out I will apply to our 4l80e

performabuilt

iTrader: (25)

That is a monster jump I too have seen this, and the final ratio is close to the same as the 60e. or the 80e but still should be and interesting unit when its time comes

N4cer

iTrader: (11)

FI and only making 550rwhp? Sounds like the Corvette guys have too much money and not enough brains.

ChocoTaco369

Someone taking a stock LS2 at 400 horsepower, then adding a blower and seeing ~690 bhp...sounds pretty good to me.

02NBMWS6

iTrader: (22)

anything over 500wheel would sound good to someone stock!

jk man

GT Griller

iTrader: (8)

This is all i would need to hear if i was in ur situation man....give them a shot!!!